[PATCH] ARM i.MX6SL: Add Kindle generation 6/7 support

[PATCH] ARM i.MX6SL: Add Kindle generation 6/7 support

[Alexander Kurz]

Four Amazon Kindle 6th and 7th generation e-book readers were considered
for this patch, referred by their models
* DP75SDI "PINOT_WFO" (256MB) "Kindle Paperwhite 2" 6th gen
* DP75SDI "Muscat WFO" (512MB) "Kindle Paperwhite 3" 7th gen
* WP63GW "Kindle" 7th gen (512MB)
* NM460GZ "Voyage" 7th gen (512MB)
Kindle e-book readers from generation 6 and 7 use the i.MX6SL and an
are shipped with a factory-adapted u-boot image. Vendor software image
updates for these models stopped around 2021 to 2023.

Add experimental support for the kindle gen 6/7 models and make barebox
an optional drop-in replacement for the original bootloader.
Required PMIC settings are implemented as script.

Notable features tested on all models:
- Support for eMMC, USB, UART, I2C and SPI.
- LPDDR2 setup is done via DCD, the same imximage may be used
  for USB-startup and for installation.
- Support for vendor specific ATAGs that are required by the Kindle-System.
- usbserial barebox console access for 10 seconds after startup.

Known issues:
- Reset on models kindle6-dp75sdi and nm460gz does not work and triggers
  microcode USB download boot.
- No recovery (without soldering) like USB boot known after e.g. a failed
  flashing attempt.

Signed-off-by: Alexander Kurz <akurz@blala.de>
---
 .../boards/imx/amazon-kindle-6-7.rst          |  94 ++++++++
 arch/arm/boards/Makefile                      |   1 +
 arch/arm/boards/kindle-mx6sl/Makefile         |   5 +
 arch/arm/boards/kindle-mx6sl/board.c          | 213 ++++++++++++++++++
 .../defaultenv-kindle-mx6sl/boot/mmc_kernel   |  11 +
 .../defaultenv-kindle-mx6sl/init/pmic         |  32 +++
 .../defaultenv-kindle-mx6sl/init/usbserial    |   4 +
 .../nv/autoboot_timeout                       |   1 +
 .../defaultenv-kindle-mx6sl/nv/boot.default   |   1 +
 .../nv/linux.bootargs.base                    |   1 +
 .../nv/linux.bootargs.console                 |   1 +
 .../nv/linux.bootargs.video                   |   1 +
 .../flash-header-kindle-mx6sl-256m.imxcfg     | 126 +++++++++++
 .../flash-header-kindle-mx6sl-512m.imxcfg     | 126 +++++++++++
 arch/arm/boards/kindle-mx6sl/lowlevel.c       |  85 +++++++
 arch/arm/configs/kindle-gen-6-7_defconfig     |  89 ++++++++
 arch/arm/dts/Makefile                         |   4 +
 arch/arm/dts/imx6sl-kindle-common.dtsi        | 167 ++++++++++++++
 arch/arm/dts/imx6sl-kindle-nm460gz.dts        |  69 ++++++
 arch/arm/dts/imx6sl-kindle-wp63gw.dts         |  44 ++++
 arch/arm/dts/imx6sl-kindle6-dp75sdi.dts       |  55 +++++
 arch/arm/dts/imx6sl-kindle7-dp75sdi.dts       |  55 +++++
 arch/arm/mach-imx/Kconfig                     |  17 ++
 images/Makefile.imx                           |  21 ++
 24 files changed, 1223 insertions(+)
 create mode 100644 Documentation/boards/imx/amazon-kindle-6-7.rst
 create mode 100644 arch/arm/boards/kindle-mx6sl/Makefile
 create mode 100644 arch/arm/boards/kindle-mx6sl/board.c
 create mode 100644 arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/boot/mmc_kernel
 create mode 100644 arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/init/pmic
 create mode 100644 arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/init/usbserial
 create mode 100644 arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/nv/autoboot_timeout
 create mode 100644 arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/nv/boot.default
 create mode 100644 arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/nv/linux.bootargs.base
 create mode 100644 arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/nv/linux.bootargs.console
 create mode 100644 arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/nv/linux.bootargs.video
 create mode 100644 arch/arm/boards/kindle-mx6sl/flash-header-kindle-mx6sl-256m.imxcfg
 create mode 100644 arch/arm/boards/kindle-mx6sl/flash-header-kindle-mx6sl-512m.imxcfg
 create mode 100644 arch/arm/boards/kindle-mx6sl/lowlevel.c
 create mode 100644 arch/arm/configs/kindle-gen-6-7_defconfig
 create mode 100644 arch/arm/dts/imx6sl-kindle-common.dtsi
 create mode 100644 arch/arm/dts/imx6sl-kindle-nm460gz.dts
 create mode 100644 arch/arm/dts/imx6sl-kindle-wp63gw.dts
 create mode 100644 arch/arm/dts/imx6sl-kindle6-dp75sdi.dts
 create mode 100644 arch/arm/dts/imx6sl-kindle7-dp75sdi.dts

diff --git a/Documentation/boards/imx/amazon-kindle-6-7.rst b/Documentation/boards/imx/amazon-kindle-6-7.rst
new file mode 100644
index 0000000000..c7a5ef9424
--- /dev/null
+++ b/Documentation/boards/imx/amazon-kindle-6-7.rst
@@ -0,0 +1,94 @@
+Amazon Kindle 6/7 (Paperwhite 2/3, Kindle 7th gen and Voyage)
+=============================================================
+
+Four models of the Amazon Kindle e-Book readers are considered as members
+of the 6th and 7th generation:
+
+* DP75SDI "PINOT_WFO" (256MB) "Kindle Paperwhite 2" 6th gen
+* DP75SDI "Muscat WFO" (512MB) "Kindle Paperwhite 3" 7th gen
+* WP63GW (512MB) "Kindle" 7th gen
+* NM460GZ (512MB) "Voyage" 7th gen
+
+Those e-book readers share a common set of hardware:
+
+* Freescale i.MX6SL SOC
+* 256MB or 512MB of LPDDR2
+* eMMC storage
+* MAX77696A PMIC
+
+The devices boot up in internal boot mode from eMMC boot partition 1
+and are shipped with a vendor modified u-boot imximage based on u-boot
+v2009.08.
+
+According to the availability of source code tarballs on the amazon website
+"Source Code Notice for Kindle E-Readers and Fire Tablets", availability of
+factory image updates seem to have been terminated between 2021 and 2023.
+
+This device is battery-powered and there is no way to switch the device off.
+When the device is inactive, the Kindle software will first reduce the
+power consumption to a few milliamps of battery power, after some minutes
+the power consumption is further reduced to sub-milliamp level. Keeping
+iomux pullups switched on at standby may significantly drain your battery.
+
+Building barebox
+----------------
+
+``make kindle-gen-6-7_defconfig`` should get you a working config.
+
+Uploading barebox
+-----------------
+
+Similar to the 4/5 gen devices, console access to gen 6/7 kindles is
+available via the Micro-USB connector when a 30k Ohm resistor to GND
+is used on the sense pin: D- will become TXD, D+ RXD.
+
+From the uboot shell, the barebox image may be chainloaded e.g. like
+
+   .. code-block:: console
+
+        $ bist
+        $ loady 0x80000000
+        $ go 0x80001000
+
+Booting the devices from USB is more demanding and will likely require
+opening of the device and desoldering of a metal shield.
+All devices feature just a single power button which may be used to reset
+the device. Unlike the models of the 4th generation where a separate
+button is available to boot from USB, such buttons do not exist here.
+Button pads on the PCB are not populated and USB boot mode by
+pin-strapping seems to be disabled by fuse settings. To put the device
+into USB boot mode, the eMMC may be disabled temporarily.
+
+1. Connect the Kindle to your host computer with a USB cable.
+2. Disable the eMMC
+   * for the DP75SDI pull the left resistor left of TP806/TP807 (below
+     TP914) facing the eMMC to zero.
+2. Power down the device by holding the power button until the power LED goes
+   dark (about 12-15 seconds).
+3. Release the power button.
+4. Free the eMMC pin.
+5. After 10-20 seconds, a new USB device named ``SE Blank MEGREZ`` should
+   appear on your host computer.
+6. Use imx-usb-loader to boot from USB.
+
+   .. code-block:: console
+
+        $ scripts/imx/imx-usb-loader images/barebox-kindle6-dp75sdi.img
+
+A USB serial ACM console will be launched by a barebox init script
+for 10 seconds after boot.
+
+Installing barebox
+------------------
+
+Barebox may be used as drop-in replacement for the shipped bootloader, when
+the imximg fits into 384000 bytes, compression like IMAGE_COMPRESSION_XZKERN
+might be required for this. When installing the barebox imximg on
+the eMMC, take care not to overwrite the vendor supplied serial numbers and
+other data stored on the eMMC. All 6th and 7th gen devices seem to share the
+same disk layout. E.g. just write the imx-header and the application section:
+
+.. code-block:: console
+
+        $ loady -t usbserial
+        $ memcpy -s barebox-kindle6-dp75sdi.img -d /dev/mmc1.boot0 0x400 0x400 0x5dc00
diff --git a/arch/arm/boards/Makefile b/arch/arm/boards/Makefile
index f73285ede9..cc32dff2a5 100644
--- a/arch/arm/boards/Makefile
+++ b/arch/arm/boards/Makefile
@@ -141,6 +141,7 @@ obj-$(CONFIG_MACH_TNY_A9260)			+= tny-a926x/
 obj-$(CONFIG_MACH_TNY_A9263)			+= tny-a926x/
 obj-$(CONFIG_MACH_TNY_A9G20)			+= tny-a926x/
 obj-$(CONFIG_MACH_KINDLE_MX50)			+= kindle-mx50/
+obj-$(CONFIG_MACH_KINDLE_6_7)			+= kindle-mx6sl/
 obj-$(CONFIG_MACH_TORADEX_COLIBRI_T20)		+= toradex-colibri-t20/
 obj-$(CONFIG_MACH_TOSHIBA_AC100)		+= toshiba-ac100/
 obj-$(CONFIG_MACH_TQMA53)			+= tqma53/
diff --git a/arch/arm/boards/kindle-mx6sl/Makefile b/arch/arm/boards/kindle-mx6sl/Makefile
new file mode 100644
index 0000000000..bb9aca5b96
--- /dev/null
+++ b/arch/arm/boards/kindle-mx6sl/Makefile
@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+obj-y += board.o
+lwl-y += lowlevel.o
+bbenv-y += defaultenv-kindle-mx6sl
diff --git a/arch/arm/boards/kindle-mx6sl/board.c b/arch/arm/boards/kindle-mx6sl/board.c
new file mode 100644
index 0000000000..38577a3006
--- /dev/null
+++ b/arch/arm/boards/kindle-mx6sl/board.c
@@ -0,0 +1,213 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+// SPDX-FileCopyrightText: 2025 Alexander Kurz <akurz@blala.de>
+
+#include <common.h>
+#include <envfs.h>
+#include <environment.h>
+#include <init.h>
+#include <io.h>
+#include <param.h>
+#include <magicvar.h>
+#include <libfile.h>
+#include <globalvar.h>
+#include <asm/armlinux.h>
+#include <asm/io.h>
+#include <linux/sizes.h>
+#include <mach/imx/generic.h>
+#include <mach/imx/imx6-regs.h>
+#include <mach/imx/imx6.h>
+#include <asm/mach-types.h>
+
+/* 16 byte id for serial number */
+#define ATAG_SERIAL16   0x5441000a
+/* 16 byte id for a board revision */
+#define ATAG_REVISION16 0x5441000b
+/* mac address / secret */
+#define ATAG_MACADDR    0x5441000d
+/* 2x 16 byte /proc/bootmode */
+#define ATAG_BOOTMODE   0x5441000f
+
+struct tag_char16 {
+	char data[16];
+};
+
+struct tag_macaddr {
+	char address[12];
+	char secret[20];
+};
+
+struct tag_bootmode {
+	char boot[16];
+	char post[16];
+};
+
+static struct tag *setup_16char_tag(struct tag *params, uint32_t tag,
+					const char *value)
+{
+	struct tag_char16 *target;
+
+	target = ((void *) params) + sizeof(struct tag_header);
+	params->hdr.tag = tag;
+	params->hdr.size = tag_size(tag_char16);
+	memset(target->data, 0, sizeof(target->data));
+	/* don't care for missing null terminators */
+	strncpy(target->data, value, sizeof(target->data));
+	return tag_next(params);
+}
+
+static struct tag *setup_macaddr_tag(struct tag *params, uint32_t tag,
+				    const char *addr, const char *secret)
+{
+	struct tag_macaddr *target;
+
+	target = ((void *) params) + sizeof(struct tag_header);
+	params->hdr.tag = tag;
+	params->hdr.size = tag_size(tag_macaddr);
+	memset(target->address, 0, sizeof(target->address));
+	memset(target->secret, 0, sizeof(target->secret));
+	strncpy(target->address, addr, sizeof(target->address));
+	strncpy(target->secret, secret, sizeof(target->secret));
+	return tag_next(params);
+}
+
+static struct tag *setup_bootmode_tag(struct tag *params, uint32_t tag,
+				    const char *bootmode, const char *postmode)
+{
+	struct tag_bootmode *target;
+
+	target = ((void *) params) + sizeof(struct tag_header);
+	params->hdr.tag = tag;
+	params->hdr.size = tag_size(tag_macaddr);
+	memset(target->boot, 0, sizeof(target->boot));
+	memset(target->post, 0, sizeof(target->post));
+	strncpy(target->boot, bootmode, sizeof(target->boot));
+	strncpy(target->post, postmode, sizeof(target->post));
+	return tag_next(params);
+}
+
+
+static const char *get_env_char_tag(const char *tag, const char *defaultval)
+{
+	const char *value;
+
+	value = getenv(tag);
+	if (!value) {
+		printf("env var %s not found, using default\n", tag);
+		return defaultval;
+	}
+	return value;
+}
+
+BAREBOX_MAGICVAR(global.board.serial16,
+	"The device serial in ATAG_SERIAL16, visible in /proc/cpuinfo");
+BAREBOX_MAGICVAR(global.board.revision16,
+	"The boardid in ATAG_REVISION16 to fill /proc/boardid");
+BAREBOX_MAGICVAR(global.board.mac,
+	"The wifi MAC in ATAG_MACADDR visible as /proc/mac_addr");
+BAREBOX_MAGICVAR(global.board.sec,
+	"The sec code in ATAG_MACADDR visible as /proc/mac_sec");
+BAREBOX_MAGICVAR(global.board.bootmode,
+	"The bootmode in ATAG_BOOTMODE to fill /proc/bootmode");
+BAREBOX_MAGICVAR(global.board.postmode,
+	"The postmode in ATAG_BOOTMODE to fill /proc/postmode");
+
+static struct envdata {
+	size_t offset;
+	size_t size;
+	const char *env_name;
+	char *data;
+} kindle_mx6sl_boardinfo[] = {
+	{ 0x0,  16, "board.serial16" },
+	{ 0x60, 16, "board.revision16" },
+	{ 0x30, 16, "board.mac" },
+	{ 0x40, 20, "board.sec" },
+	{ 0x1000, 16, "board.bootmode" },
+	{ 0x1010, 16, "board.postmode" },
+};
+
+/* The Kernels several custom ATAGs */
+static struct tag *kindle_mx6sl_append_atags(struct tag *params)
+{
+	params = setup_16char_tag(params, ATAG_SERIAL16,
+			get_env_char_tag("global.board.serial16",
+				"0000000000000000"));
+	params = setup_16char_tag(params, ATAG_REVISION16,
+			get_env_char_tag("global.board.revision16",
+				"0000000000000000"));
+	params = setup_macaddr_tag(params, ATAG_MACADDR,
+			get_env_char_tag("global.board.mac",
+				"000000000000"),
+			get_env_char_tag("global.board.sec",
+				"00000000000000000000"));
+	params = setup_bootmode_tag(params, ATAG_BOOTMODE,
+			get_env_char_tag("global.board.bootmode", ""),
+			get_env_char_tag("global.board.postmode", ""));
+	return params;
+}
+
+
+static void kindle_rev_init(const char *part, struct envdata *env, size_t num)
+{
+	void *buf;
+	int ret;
+
+	ret = read_file_2(part, NULL, &buf, 0x1060);
+	if (ret && ret != -EFBIG) {
+		pr_err("Could not read board info from %s\n", part);
+		return;
+	}
+	for (int i = 0; i < num; i++) {
+		size_t offset = env[i].offset;
+		size_t size = env[i].size;
+		const char *name = env[i].env_name;
+
+		env[i].data = xzalloc(size + 1);
+		env[i].data[size] = 0;
+		memcpy(env[i].data, buf + offset, size);
+		globalvar_add_simple_string(name, &env[i].data);
+	}
+
+	free(buf);
+}
+
+static int is_mx6sl_kindle(void)
+{
+	return of_machine_is_compatible("amazon,imx6sl-kindle6-dp75sdi") ||
+		of_machine_is_compatible("amazon,imx6sl-kindle7-dp75sdi") ||
+		of_machine_is_compatible("amazon,imx6sl-kindle-wp63gw") ||
+		of_machine_is_compatible("amazon,imx6sl-kindle-nm460gz");
+}
+
+static int kindle_mx6sl_late_init(void)
+{
+	if (!is_mx6sl_kindle())
+		return 0;
+
+	/* Compatibility ATAGs for original kernel */
+	armlinux_set_atag_appender(kindle_mx6sl_append_atags);
+
+	kindle_rev_init("/dev/mmc1.boot0.userdata", kindle_mx6sl_boardinfo,
+		ARRAY_SIZE(kindle_mx6sl_boardinfo));
+
+	return 0;
+}
+late_initcall(kindle_mx6sl_late_init);
+
+static int kindle6_device_init(void)
+{
+	struct device *dev;
+
+	if (!is_mx6sl_kindle())
+		return 0;
+
+	/* Probe the eMMC to allow reading the board serial and revision */
+	dev = get_device_by_name("mmc1");
+	if (dev)
+		dev_set_param(dev, "probe", "1");
+
+	defaultenv_append_directory(defaultenv_kindle_mx6sl);
+
+	return 0;
+}
+
+device_initcall(kindle6_device_init);
diff --git a/arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/boot/mmc_kernel b/arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/boot/mmc_kernel
new file mode 100644
index 0000000000..518110b8fd
--- /dev/null
+++ b/arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/boot/mmc_kernel
@@ -0,0 +1,11 @@
+#!/bin/sh
+# Boot the Amazon factory-shipped kernel uimage stored on
+# the eMMC at CONFIG_MMC_BOOTFLASH_ADDR 0x41000
+
+# Force ATAG boot
+global.bootm.boot_atag=true
+
+global linux.bootargs.dyn.log="log_pos_goal=0x8fff0000"
+global linux.bootargs.dyn.root="rootwait root=/dev/mmcblk0p1 ro"
+
+bootm -c /dev/mmc1.kernel
diff --git a/arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/init/pmic b/arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/init/pmic
new file mode 100644
index 0000000000..efa02843e6
--- /dev/null
+++ b/arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/init/pmic
@@ -0,0 +1,32 @@
+#!/bin/sh
+
+# MAX77696 PMIC setup.
+#
+# Common settings for gen 6/7 kindles
+# LDO_L07_CNFG1_REG
+i2c_write -b 0 -a 0x3c -r 0x4f 0x70
+# LDO_L10_CNFG1_REG
+i2c_write -b 0 -a 0x3c -r 0x55 0xf4
+
+i2c_write -b 0 -a 0x3c -r 0x2 0x36
+# BUCK_VOUT1_REG
+i2c_write -b 0 -a 0x3c -r 0x31 0x34
+# BUCK_VOUTCNFG1_REG
+i2c_write -b 0 -a 0x3c -r 0x39 0xd0
+# BUCK_VOUTCNFG2_REG
+i2c_write -b 0 -a 0x3c -r 0x3a 0xd0
+# BUCK_VOUTCNFG3_REG
+i2c_write -b 0 -a 0x3c -r 0x3b 0x40
+# BUCK_VOUTCNFG6_REG
+i2c_write -b 0 -a 0x3c -r 0x3e 0x70
+i2c_write -b 0 -a 0x3c -r 0x5e 0x04
+# VREG_EPDCNFG_REG
+i2c_write -b 0 -a 0x3c -r 0x60 0x00
+# VREG_EPDSEQ_REG / VDDQ_SET_REG
+i2c_write -b 0 -a 0x3c -r 0x69 0x18
+
+if [ "$global.model" = "kindle6-dp75sdi" -o "$global.model" = "kindle7-dp75sdi" ]; then
+	# Backlight not available on WP63GW.
+	i2c_write -b 0 -a 0x3c -r 0x6c 0x80
+	i2c_write -b 0 -a 0x3c -r 0x6d 0x20
+fi
diff --git a/arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/init/usbserial b/arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/init/usbserial
new file mode 100644
index 0000000000..c181c06da9
--- /dev/null
+++ b/arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/init/usbserial
@@ -0,0 +1,4 @@
+#!/bin/sh
+
+usbserial
+global.autoboot_timeout=10
diff --git a/arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/nv/autoboot_timeout b/arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/nv/autoboot_timeout
new file mode 100644
index 0000000000..64bb6b746d
--- /dev/null
+++ b/arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/nv/autoboot_timeout
@@ -0,0 +1 @@
+30
diff --git a/arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/nv/boot.default b/arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/nv/boot.default
new file mode 100644
index 0000000000..3118b7af45
--- /dev/null
+++ b/arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/nv/boot.default
@@ -0,0 +1 @@
+mmc_kernel
diff --git a/arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/nv/linux.bootargs.base b/arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/nv/linux.bootargs.base
new file mode 100644
index 0000000000..64d790aa7f
--- /dev/null
+++ b/arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/nv/linux.bootargs.base
@@ -0,0 +1 @@
+ip=off
diff --git a/arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/nv/linux.bootargs.console b/arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/nv/linux.bootargs.console
new file mode 100644
index 0000000000..d775310b40
--- /dev/null
+++ b/arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/nv/linux.bootargs.console
@@ -0,0 +1 @@
+console=ttymxc0,115200
diff --git a/arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/nv/linux.bootargs.video b/arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/nv/linux.bootargs.video
new file mode 100644
index 0000000000..9b4e01473b
--- /dev/null
+++ b/arch/arm/boards/kindle-mx6sl/defaultenv-kindle-mx6sl/nv/linux.bootargs.video
@@ -0,0 +1 @@
+video=mxcepdcfb:E60,bpp=8,x_mem=3M
diff --git a/arch/arm/boards/kindle-mx6sl/flash-header-kindle-mx6sl-256m.imxcfg b/arch/arm/boards/kindle-mx6sl/flash-header-kindle-mx6sl-256m.imxcfg
new file mode 100644
index 0000000000..6b1b53cf16
--- /dev/null
+++ b/arch/arm/boards/kindle-mx6sl/flash-header-kindle-mx6sl-256m.imxcfg
@@ -0,0 +1,126 @@
+# SPDX-License-Identifier: GPL-2.0-only
+# SPDX-FileCopyrightText: 2025 Alexander Kurz <akurz@blala.de>
+# SPDX-FileCopyrightText: 2012 Freescale Semiconductor, Inc.
+
+# DCD i.MX6sl SoC setup using 256MiB LPDDR2
+#
+# Initial DCD setup according to
+# Kindle_src_5.10.2_3374520058.tar.gz / uboot_2009.08.tar.gz
+# board/imx60_wario/flash_header.S
+
+loadaddr 0x80000000
+soc imx6
+ivtofs 0x400
+# CCM
+wm 32 0x020c4018 0x00260324
+
+# CCM CGR
+wm 32 0x020c4068 0xffffffff
+wm 32 0x020c406c 0xffffffff
+wm 32 0x020c4070 0xffffffff
+wm 32 0x020c4074 0xffffffff
+wm 32 0x020c4078 0xffffffff
+wm 32 0x020c407c 0xffffffff
+wm 32 0x020c4080 0xffffffff
+wm 32 0x020c4084 0xffffffff
+
+# IOMUX
+wm 32 0x020e0344 0x00003038
+wm 32 0x020e0348 0x00003038
+wm 32 0x020e034c 0x00003038
+wm 32 0x020e0350 0x00003038
+
+wm 32 0x020e030c 0x00000020
+wm 32 0x020e0310 0x00000020
+wm 32 0x020e0314 0x00000020
+wm 32 0x020e0318 0x00000020
+
+wm 32 0x020e0300 0x00000020
+wm 32 0x020e031c 0x00000020
+wm 32 0x020e0338 0x00000020
+wm 32 0x020e0320 0x00080020
+wm 32 0x020e032c 0x00080000
+
+wm 32 0x020e0330 0x00000020
+wm 32 0x020e0334 0x00000020
+wm 32 0x020e033c 0x00000008
+wm 32 0x020e0340 0x00000008
+wm 32 0x020e0344 0x00003020
+wm 32 0x020e0348 0x00003020
+wm 32 0x020e034c 0x00003020
+wm 32 0x020e0350 0x00003020
+
+wm 32 0x020e032c 0x00000000
+wm 32 0x020e05c4 0x00000020
+wm 32 0x020e05cc 0x00000020
+wm 32 0x020e05d0 0x00080000
+wm 32 0x020e05d4 0x00000020
+wm 32 0x020e05d8 0x00000020
+wm 32 0x020e05ac 0x00000020
+wm 32 0x020e05c8 0x00000020
+wm 32 0x020e05b0 0x00020000
+wm 32 0x020e05b4 0x00000000
+wm 32 0x020e05c0 0x00020000
+wm 32 0x020e05bc 0x00001000
+
+# MMDC
+# MMDC0_MDSCR, set the Configuration request bit during MMDC set up
+wm 32 0x021b001c 0x00008000
+# LPDDR2 ZQ params
+wm 32 0x021b085c 0x1b4700c7
+# DDR_PHY_P0_MPZQHWCTRL
+wm 32 0x021b0800 0xa1390003
+wm 32 0x021b0890 0x00400000
+# frc_msr
+wm 32 0x021b08b8 0x00000800
+# DDR_PHY_P0_MPREDQBY0DL3 - DDR_PHY_P0_MPREDQBY3DL3
+wm 32 0x021b081c 0x33333333
+wm 32 0x021b0820 0x33333333
+wm 32 0x021b0824 0x33333333
+wm 32 0x021b0828 0x33333333
+wm 32 0x021b082c 0xf3333333
+wm 32 0x021b0830 0xf3333333
+wm 32 0x021b0834 0xf3333333
+wm 32 0x021b0838 0xf3333333
+# read calibration
+wm 32 0x021b0848 0x4241444a
+# write calibration
+wm 32 0x021b0850 0x3030312b
+# dqs gating dis
+wm 32 0x021b083c 0x20000000
+wm 32 0x021b0840 0x0
+# fine tune duty cyc to low
+wm 32 0x021b08c0 0x24911492
+# frc_msr
+wm 32 0x021b08b8 0x00000800
+# MMDC0_MDCFG0, MDPDC, MDCFG1, MDCFG2
+wm 32 0x021b000c 0x33374133
+wm 32 0x021b0004 0x00020024
+wm 32 0x021b0010 0x00100A82
+wm 32 0x021b0014 0x00000093
+# MMDC0_MDMISC, MDRWD, MDOR
+wm 32 0x021b0018 0x00001688
+wm 32 0x021b002c 0x0f9f26d2
+wm 32 0x021b0030 0x009F0E10
+wm 32 0x021b0030 0x00000010
+# MMDC0_MDCFG3LP, MDOTC
+wm 32 0x021b0038 0x00190778
+wm 32 0x021b0008 0x00000000
+# CS0_END = 0x8fffffff, 256MB
+wm 32 0x021b0040 0x00000047
+# MMDC0_MDCTL 256MB, SDE0 only
+wm 32 0x021b0000 0x83010000
+# MRW
+wm 32 0x021b001c 0x003f8030
+wm 32 0x021b001c 0xff0a8030
+wm 32 0x021b001c 0x82018030
+wm 32 0x021b001c 0x04028030
+wm 32 0x021b001c 0x03038030
+# final DDR setup
+wm 32 0x021b0800 0xa1310003
+wm 32 0x021b0020 0x00001800
+wm 32 0x021b0818 0x00000000
+wm 32 0x021b08b8 0x00000800
+wm 32 0x021b0004 0x00025564
+wm 32 0x021b0404 0x00011006
+wm 32 0x021b001c 0x00000000
diff --git a/arch/arm/boards/kindle-mx6sl/flash-header-kindle-mx6sl-512m.imxcfg b/arch/arm/boards/kindle-mx6sl/flash-header-kindle-mx6sl-512m.imxcfg
new file mode 100644
index 0000000000..6af6341daa
--- /dev/null
+++ b/arch/arm/boards/kindle-mx6sl/flash-header-kindle-mx6sl-512m.imxcfg
@@ -0,0 +1,126 @@
+# SPDX-License-Identifier: GPL-2.0-only
+# SPDX-FileCopyrightText: 2025 Alexander Kurz <akurz@blala.de>
+# SPDX-FileCopyrightText: 2012 Freescale Semiconductor, Inc.
+
+# DCD i.MX6sl SoC setup using 512MiB LPDDR2
+#
+# Initial DCD setup according to
+# Kindle_src_5.10.2_3374520058.tar.gz / uboot_2009.08.tar.gz
+# board/imx60_wario/flash_header.S
+
+loadaddr 0x80000000
+soc imx6
+ivtofs 0x400
+# CCM
+wm 32 0x020c4018 0x00260324
+
+# CCM CGR
+wm 32 0x020c4068 0xffffffff
+wm 32 0x020c406c 0xffffffff
+wm 32 0x020c4070 0xffffffff
+wm 32 0x020c4074 0xffffffff
+wm 32 0x020c4078 0xffffffff
+wm 32 0x020c407c 0xffffffff
+wm 32 0x020c4080 0xffffffff
+wm 32 0x020c4084 0xffffffff
+
+# IOMUX
+wm 32 0x020e0344 0x00003038
+wm 32 0x020e0348 0x00003038
+wm 32 0x020e034c 0x00003038
+wm 32 0x020e0350 0x00003038
+
+wm 32 0x020e030c 0x00000020
+wm 32 0x020e0310 0x00000020
+wm 32 0x020e0314 0x00000020
+wm 32 0x020e0318 0x00000020
+
+wm 32 0x020e0300 0x00000020
+wm 32 0x020e031c 0x00000020
+wm 32 0x020e0338 0x00000020
+wm 32 0x020e0320 0x00080020
+wm 32 0x020e032c 0x00080000
+
+wm 32 0x020e0330 0x00000020
+wm 32 0x020e0334 0x00000020
+wm 32 0x020e033c 0x00000008
+wm 32 0x020e0340 0x00000008
+wm 32 0x020e0344 0x00003020
+wm 32 0x020e0348 0x00003020
+wm 32 0x020e034c 0x00003020
+wm 32 0x020e0350 0x00003020
+
+wm 32 0x020e032c 0x00000000
+wm 32 0x020e05c4 0x00000020
+wm 32 0x020e05cc 0x00000020
+wm 32 0x020e05d0 0x00080000
+wm 32 0x020e05d4 0x00000020
+wm 32 0x020e05d8 0x00000020
+wm 32 0x020e05ac 0x00000020
+wm 32 0x020e05c8 0x00000020
+wm 32 0x020e05b0 0x00020000
+wm 32 0x020e05b4 0x00000000
+wm 32 0x020e05c0 0x00020000
+wm 32 0x020e05bc 0x00001000
+
+# MMDC
+# MMDC0_MDSCR, set the Configuration request bit during MMDC set up
+wm 32 0x021b001c 0x00008000
+# LPDDR2 ZQ params
+wm 32 0x021b085c 0x1b4700c7
+# DDR_PHY_P0_MPZQHWCTRL
+wm 32 0x021b0800 0xa1390003
+wm 32 0x021b0890 0x00400000
+# frc_msr
+wm 32 0x021b08b8 0x00000800
+# DDR_PHY_P0_MPREDQBY0DL3 - DDR_PHY_P0_MPREDQBY3DL3
+wm 32 0x021b081c 0x33333333
+wm 32 0x021b0820 0x33333333
+wm 32 0x021b0824 0x33333333
+wm 32 0x021b0828 0x33333333
+wm 32 0x021b082c 0xf3333333
+wm 32 0x021b0830 0xf3333333
+wm 32 0x021b0834 0xf3333333
+wm 32 0x021b0838 0xf3333333
+# read calibration
+wm 32 0x021b0848 0x4241444a
+# write calibration
+wm 32 0x021b0850 0x3030312b
+# dqs gating dis
+wm 32 0x021b083c 0x20000000
+wm 32 0x021b0840 0x0
+# fine tune duty cyc to low
+wm 32 0x021b08c0 0x24911492
+# frc_msr
+wm 32 0x021b08b8 0x00000800
+# MMDC0_MDCFG0, MDPDC, MDCFG1, MDCFG2
+wm 32 0x021b000c 0x33374133
+wm 32 0x021b0004 0x00020024
+wm 32 0x021b0010 0x00100A82
+wm 32 0x021b0014 0x00000093
+# MMDC0_MDMISC, MDRWD, MDOR
+wm 32 0x021b0018 0x00001688
+wm 32 0x021b002c 0x0f9f26d2
+wm 32 0x021b0030 0x009F0E10
+wm 32 0x021b0030 0x00000010
+# MMDC0_MDCFG3LP, MDOTC
+wm 32 0x021b0038 0x00190778
+wm 32 0x021b0008 0x00000000
+# CS0_END = 0x9fffffff, 512MB
+wm 32 0x021b0040 0x0000004f
+# MMDC0_MDCTL, SDE_1 disabled
+wm 32 0x021b0000 0x83110000
+# MRW
+wm 32 0x021b001c 0x003f8030
+wm 32 0x021b001c 0xff0a8030
+wm 32 0x021b001c 0x82018030
+wm 32 0x021b001c 0x04028030
+wm 32 0x021b001c 0x03038030
+# final DDR setup
+wm 32 0x021b0800 0xa1310003
+wm 32 0x021b0020 0x00001800
+wm 32 0x021b0818 0x00000000
+wm 32 0x021b08b8 0x00000800
+wm 32 0x021b0004 0x00025564
+wm 32 0x021b0404 0x00011006
+wm 32 0x021b001c 0x00000000
diff --git a/arch/arm/boards/kindle-mx6sl/lowlevel.c b/arch/arm/boards/kindle-mx6sl/lowlevel.c
new file mode 100644
index 0000000000..3b823bf061
--- /dev/null
+++ b/arch/arm/boards/kindle-mx6sl/lowlevel.c
@@ -0,0 +1,85 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <mach/imx/debug_ll.h>
+#include <common.h>
+#include <linux/sizes.h>
+#include <io.h>
+#include <asm/barebox-arm-head.h>
+#include <asm/barebox-arm.h>
+#include <asm/sections.h>
+#include <asm/cache.h>
+#include <asm/mmu.h>
+#include <mach/imx/imx6.h>
+
+extern char __dtb_imx6sl_kindle_wp63gw_start[];
+extern char __dtb_imx6sl_kindle6_dp75sdi_start[];
+extern char __dtb_imx6sl_kindle7_dp75sdi_start[];
+extern char __dtb_imx6sl_kindle_nm460gz_start[];
+
+ENTRY_FUNCTION(start_imx6sl_kindle_wp63gw, r0, r1, r2)
+{
+	void *fdt;
+
+	imx6_cpu_lowlevel_init();
+
+	arm_setup_stack(0x00920000);
+
+	if (IS_ENABLED(CONFIG_DEBUG_LL)) {
+		writel(0x4, 0x020e016c);
+		imx6_uart_setup_ll();
+	}
+
+	fdt = __dtb_imx6sl_kindle_wp63gw_start + get_runtime_offset();
+	barebox_arm_entry(0x80000000, SZ_256M, fdt);
+}
+
+ENTRY_FUNCTION(start_imx6sl_kindle6_dp75sdi, r0, r1, r2)
+{
+	void *fdt;
+
+	imx6_cpu_lowlevel_init();
+
+	arm_setup_stack(0x00920000);
+
+	if (IS_ENABLED(CONFIG_DEBUG_LL)) {
+		writel(0x4, 0x020e016c);
+		imx6_uart_setup_ll();
+	}
+
+	fdt = __dtb_imx6sl_kindle6_dp75sdi_start + get_runtime_offset();
+	barebox_arm_entry(0x80000000, SZ_256M, fdt);
+}
+
+ENTRY_FUNCTION(start_imx6sl_kindle7_dp75sdi, r0, r1, r2)
+{
+	void *fdt;
+
+	imx6_cpu_lowlevel_init();
+
+	arm_setup_stack(0x00920000);
+
+	if (IS_ENABLED(CONFIG_DEBUG_LL)) {
+		writel(0x4, 0x020e016c);
+		imx6_uart_setup_ll();
+	}
+
+	fdt = __dtb_imx6sl_kindle7_dp75sdi_start + get_runtime_offset();
+	barebox_arm_entry(0x80000000, SZ_512M, fdt);
+}
+
+ENTRY_FUNCTION(start_imx6sl_kindle_nm460gz, r0, r1, r2)
+{
+	void *fdt;
+
+	imx6_cpu_lowlevel_init();
+
+	arm_setup_stack(0x00920000);
+
+	if (IS_ENABLED(CONFIG_DEBUG_LL)) {
+		writel(0x4, 0x020e016c);
+		imx6_uart_setup_ll();
+	}
+
+	fdt = __dtb_imx6sl_kindle_nm460gz_start + get_runtime_offset();
+	barebox_arm_entry(0x80000000, SZ_512M, fdt);
+}
diff --git a/arch/arm/configs/kindle-gen-6-7_defconfig b/arch/arm/configs/kindle-gen-6-7_defconfig
new file mode 100644
index 0000000000..9155fb45a3
--- /dev/null
+++ b/arch/arm/configs/kindle-gen-6-7_defconfig
@@ -0,0 +1,89 @@
+CONFIG_ARCH_IMX=y
+CONFIG_MACH_KINDLE_6_7=y
+CONFIG_IMX_IIM=y
+CONFIG_IMX_IIM_FUSE_BLOW=y
+CONFIG_THUMB2_BAREBOX=y
+CONFIG_ARM_OPTIMZED_STRING_FUNCTIONS=y
+CONFIG_ARM_UNWIND=y
+CONFIG_BOOT_ATAGS=y
+CONFIG_IMAGE_COMPRESSION_XZKERN=y
+CONFIG_MMU=y
+CONFIG_BAREBOX_MAX_IMAGE_SIZE=0x5dc00
+CONFIG_STACK_SIZE=0x10000
+CONFIG_MALLOC_SIZE=0x0
+CONFIG_KALLSYMS=y
+CONFIG_HUSH_FANCY_PROMPT=y
+CONFIG_CMDLINE_EDITING=y
+CONFIG_AUTO_COMPLETE=y
+CONFIG_BOOTM_SHOW_TYPE=y
+CONFIG_BOOTM_VERBOSE=y
+CONFIG_BOOTM_INITRD=y
+CONFIG_BOOTM_OFTREE_UIMAGE=y
+CONFIG_BLSPEC=y
+CONFIG_CONSOLE_ACTIVATE_NONE=y
+CONFIG_DEFAULT_ENVIRONMENT_GENERIC_NEW=y
+CONFIG_RESET_SOURCE=y
+CONFIG_CMD_DMESG=y
+CONFIG_LONGHELP=y
+CONFIG_CMD_IOMEM=y
+CONFIG_CMD_IMD=y
+CONFIG_CMD_MEMINFO=y
+CONFIG_CMD_ARM_MMUINFO=y
+CONFIG_CMD_REGULATOR=y
+# CONFIG_CMD_BOOTU is not set
+CONFIG_CMD_GO=y
+CONFIG_CMD_LOADY=y
+CONFIG_CMD_RESET=y
+CONFIG_CMD_UIMAGE=y
+CONFIG_CMD_PARTITION=y
+CONFIG_CMD_EXPORT=y
+CONFIG_CMD_LOADENV=y
+CONFIG_CMD_PRINTENV=y
+CONFIG_CMD_MAGICVAR=y
+CONFIG_CMD_MAGICVAR_HELP=y
+CONFIG_CMD_SAVEENV=y
+CONFIG_CMD_FILETYPE=y
+CONFIG_CMD_LN=y
+CONFIG_CMD_MD5SUM=y
+CONFIG_CMD_UNCOMPRESS=y
+CONFIG_CMD_LET=y
+CONFIG_CMD_MSLEEP=y
+CONFIG_CMD_READF=y
+CONFIG_CMD_SLEEP=y
+CONFIG_CMD_ECHO_E=y
+CONFIG_CMD_EDIT=y
+CONFIG_CMD_READLINE=y
+CONFIG_CMD_TIMEOUT=y
+CONFIG_CMD_MEMTEST=y
+CONFIG_CMD_MM=y
+CONFIG_CMD_CLK=y
+CONFIG_CMD_DETECT=y
+CONFIG_CMD_GPIO=y
+CONFIG_CMD_I2C=y
+CONFIG_CMD_SPI=y
+CONFIG_CMD_USBGADGET=y
+CONFIG_CMD_OF_NODE=y
+CONFIG_CMD_OF_PROPERTY=y
+CONFIG_CMD_OFTREE=y
+CONFIG_CMD_TIME=y
+CONFIG_OF_BAREBOX_DRIVERS=y
+CONFIG_MTD=y
+CONFIG_MTD_M25P80=y
+CONFIG_USB_HOST=y
+CONFIG_USB_IMX_CHIPIDEA=y
+CONFIG_USB_EHCI=y
+CONFIG_USB_GADGET=y
+CONFIG_USB_GADGET_SERIAL=y
+CONFIG_MCI=y
+CONFIG_MCI_MMC_BOOT_PARTITIONS=y
+CONFIG_MCI_IMX_ESDHC=y
+CONFIG_EEPROM_AT25=y
+CONFIG_WATCHDOG=y
+CONFIG_WATCHDOG_IMX=y
+CONFIG_MXS_APBH_DMA=y
+CONFIG_REGULATOR=y
+CONFIG_REGULATOR_FIXED=y
+CONFIG_GENERIC_PHY=y
+CONFIG_FS_EXT4=y
+CONFIG_FS_FAT=y
+CONFIG_FS_FAT_WRITE=y
diff --git a/arch/arm/dts/Makefile b/arch/arm/dts/Makefile
index e78722a9a7..7f434403b8 100644
--- a/arch/arm/dts/Makefile
+++ b/arch/arm/dts/Makefile
@@ -17,6 +17,10 @@ lwl-$(CONFIG_MACH_EXYNOS) += exynos8895-dreamlte.dtb.o \
 			exynos990-x1s.dtb.o
 lwl-$(CONFIG_MACH_DUCKBILL) += imx28-duckbill.dtb.o
 lwl-$(CONFIG_MACH_KINDLE_MX50) += imx50-kindle-d01100.dtb.o imx50-kindle-d01200.dtb.o imx50-kindle-ey21.dtb.o
+lwl-$(CONFIG_MACH_KINDLE_6_7) += imx6sl-kindle-wp63gw.dtb.o \
+		imx6sl-kindle6-dp75sdi.dtb.o \
+		imx6sl-kindle7-dp75sdi.dtb.o \
+		imx6sl-kindle-nm460gz.dtb.o
 lwl-$(CONFIG_MACH_EFIKA_MX_SMARTBOOK) += imx51-genesi-efika-sb.dtb.o
 lwl-$(CONFIG_MACH_ELTEC_HIPERCAM) += imx6dl-eltec-hipercam.dtb.o
 lwl-$(CONFIG_MACH_EMBEST_MARSBOARD) += imx6q-marsboard.dtb.o
diff --git a/arch/arm/dts/imx6sl-kindle-common.dtsi b/arch/arm/dts/imx6sl-kindle-common.dtsi
new file mode 100644
index 0000000000..8a98fd2bbc
--- /dev/null
+++ b/arch/arm/dts/imx6sl-kindle-common.dtsi
@@ -0,0 +1,167 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2025 Alexander Kurz <akurz@blala.de>
+ */
+
+/dts-v1/;
+
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/input/input.h>
+#include <arm/nxp/imx/imx6sl.dtsi>
+
+/ {
+	chosen {
+		stdout-path = &uart1;
+	};
+
+	reg_3p3v: regulator-3p3v {
+		compatible = "regulator-fixed";
+		regulator-name = "3P3V";
+		regulator-min-microvolt = <3300000>;
+		regulator-max-microvolt = <3300000>;
+		regulator-always-on;
+	};
+};
+
+&iomuxc {
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_hog>;
+
+	imx6sl-kindle {
+		pinctrl_uart1: uart1grp {
+			fsl,pins = <
+				MX6SL_PAD_UART1_RXD__UART1_RX_DATA	0x1b0b1
+				MX6SL_PAD_UART1_TXD__UART1_TX_DATA	0x1b0b1
+			>;
+		};
+
+		pinctrl_usdhc2: usdhc2grp {
+			fsl,pins = <
+				MX6SL_PAD_SD2_CMD__SD2_CMD		0x17059
+				MX6SL_PAD_SD2_CLK__SD2_CLK		0x10059
+				MX6SL_PAD_SD2_DAT0__SD2_DATA0		0x17059
+				MX6SL_PAD_SD2_DAT1__SD2_DATA1		0x17059
+				MX6SL_PAD_SD2_DAT2__SD2_DATA2		0x17059
+				MX6SL_PAD_SD2_DAT3__SD2_DATA3		0x17059
+			>;
+		};
+
+		pinctrl_usdhc2_100mhz: usdhc2grp100mhz {
+			fsl,pins = <
+				MX6SL_PAD_SD2_CMD__SD2_CMD		0x170b9
+				MX6SL_PAD_SD2_CLK__SD2_CLK		0x100b9
+				MX6SL_PAD_SD2_DAT0__SD2_DATA0		0x170b9
+				MX6SL_PAD_SD2_DAT1__SD2_DATA1		0x170b9
+				MX6SL_PAD_SD2_DAT2__SD2_DATA2		0x170b9
+				MX6SL_PAD_SD2_DAT3__SD2_DATA3		0x170b9
+			>;
+		};
+
+		pinctrl_usdhc2_200mhz: usdhc2grp200mhz {
+			fsl,pins = <
+				MX6SL_PAD_SD2_CMD__SD2_CMD		0x170f9
+				MX6SL_PAD_SD2_CLK__SD2_CLK		0x100f9
+				MX6SL_PAD_SD2_DAT0__SD2_DATA0		0x170f9
+				MX6SL_PAD_SD2_DAT1__SD2_DATA1		0x170f9
+				MX6SL_PAD_SD2_DAT2__SD2_DATA2		0x170f9
+				MX6SL_PAD_SD2_DAT3__SD2_DATA3		0x170f9
+			>;
+		};
+
+		pinctrl_ecspi1: ecspi1grp {
+			fsl,pins = <
+				MX6SL_PAD_ECSPI1_MISO__ECSPI1_MISO	0x400100b1
+				MX6SL_PAD_ECSPI1_MOSI__ECSPI1_MOSI	0x400100b1
+				MX6SL_PAD_ECSPI1_SCLK__ECSPI1_SCLK	0x400100b1
+				MX6SL_PAD_ECSPI1_SS0__GPIO4_IO11	0x80000000
+			>;
+		};
+
+		pinctrl_i2c1: i2c1grp {
+			fsl,pins = <
+				MX6SL_PAD_I2C1_SCL__I2C1_SCL		0x4001b8b1
+				MX6SL_PAD_I2C1_SDA__I2C1_SDA		0x4001b8b1
+			>;
+		};
+	};
+};
+
+&uart1 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_uart1>;
+	status = "okay";
+};
+
+&usdhc2 {
+	pinctrl-names = "default", "state_100mhz", "state_200mhz";
+	pinctrl-0 = <&pinctrl_usdhc2>;
+	pinctrl-1 = <&pinctrl_usdhc2_100mhz>;
+	pinctrl-2 = <&pinctrl_usdhc2_200mhz>;
+	non-removable;
+	keep-power-in-suspend;
+	enable-sdio-wakeup;
+	bus-width = <4>;
+	fsl,delay-line;
+	status = "okay";
+
+	partitions {
+		compatible = "barebox,fixed-partitions";
+		#address-cells = <1>;
+		#size-cells = <1>;
+
+		kernel: kernel@41000 {
+			label = "kernel";
+			reg = <0x41000 0xe00000>;
+		};
+	};
+
+	partitions-boot1 {
+		compatible = "barebox,fixed-partitions";
+		#address-cells = <1>;
+		#size-cells = <1>;
+
+		imx_header: imx_header@400 {
+			label = "imx_header";
+			reg = <0x400 0x800>;
+		};
+
+		self: self@1000 {
+			label = "self";
+			reg = <0x1000 0x4d000>;
+		};
+
+		userdata: userdata@5e000 {
+			label = "userdata";
+			reg = <0x5e000 0x1400>;
+		};
+	};
+};
+
+&ecspi1 {
+	fsl,spi-num-chipselects = <1>;
+	cs-gpios = <&gpio4 11 0>;
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_ecspi1>;
+	status = "okay";
+
+	flash: m25p80@0 {
+		#address-cells = <1>;
+		#size-cells = <1>;
+		compatible = "st,m25p32", "jedec,spi-nor";
+		spi-max-frequency = <2000000>;
+		reg = <0>;
+	};
+};
+
+&i2c1 {
+	clock-frequency = <100000>;
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_i2c1>;
+	status = "okay";
+};
+
+&usbotg1 {
+	phy_type = "utmi";
+	dr_mode = "peripheral";
+	status = "okay";
+};
diff --git a/arch/arm/dts/imx6sl-kindle-nm460gz.dts b/arch/arm/dts/imx6sl-kindle-nm460gz.dts
new file mode 100644
index 0000000000..606964b828
--- /dev/null
+++ b/arch/arm/dts/imx6sl-kindle-nm460gz.dts
@@ -0,0 +1,69 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2025 Alexander Kurz <akurz@blala.de>
+ */
+
+/dts-v1/;
+#include "imx6sl-kindle-common.dtsi"
+#include <dt-bindings/interrupt-controller/irq.h>
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/input/input.h>
+
+/ {
+	model = "kindle-nm460gz";
+	compatible = "amazon,imx6sl-kindle-nm460gz", "fsl,imx6sl";
+	barebox,disable-deep-probe;
+
+	memory@80000000 {
+		reg = <0x80000000 0x20000000>;
+	};
+};
+
+&iomuxc {
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_hog>;
+
+	imx6sl-kindle-nm460gz {
+		pinctrl_hog: hoggrp {
+			fsl,pins = <
+				/* Hall sensor */
+				MX6SL_PAD_KEY_ROW7__GPIO4_IO07	0x17059
+				/* Touch reset */
+				MX6SL_PAD_KEY_ROW6__GPIO4_IO05	0x17059
+				/* EMMC_3v2_EN, EMMC_1v8_EN */
+				MX6SL_PAD_FEC_RXD0__GPIO4_IO17	0x17059
+				MX6SL_PAD_FEC_MDC__GPIO4_IO23	0x17059
+				/* WLAN pwd */
+				MX6SL_PAD_KEY_ROW2__GPIO3_IO29	0x17059
+			>;
+		};
+
+		pinctrl_i2c2: i2c2grp {
+			fsl,pins = <
+				MX6SL_PAD_I2C2_SCL__I2C2_SCL	0x4001b8b1
+				MX6SL_PAD_I2C2_SDA__I2C2_SDA	0x4001b8b1
+			>;
+		};
+
+		pinctrl_i2c3: i2c3grp {
+			fsl,pins = <
+				MX6SL_PAD_EPDC_SDCE2__I2C3_SCL	0x4001b8b1
+				MX6SL_PAD_EPDC_SDCE3__I2C3_SDA	0x4001b8b1
+			>;
+		};
+	};
+};
+
+&i2c2 {
+	clock-frequency = <100000>;
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_i2c2>;
+	status = "okay";
+};
+
+&i2c3 {
+	clock-frequency = <100000>;
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_i2c3>;
+	status = "okay";
+};
diff --git a/arch/arm/dts/imx6sl-kindle-wp63gw.dts b/arch/arm/dts/imx6sl-kindle-wp63gw.dts
new file mode 100644
index 0000000000..156be77cd2
--- /dev/null
+++ b/arch/arm/dts/imx6sl-kindle-wp63gw.dts
@@ -0,0 +1,44 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2025 Alexander Kurz <akurz@blala.de>
+ */
+
+/dts-v1/;
+#include "imx6sl-kindle-common.dtsi"
+#include <dt-bindings/interrupt-controller/irq.h>
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/input/input.h>
+
+/ {
+	model = "kindle-wp63gw";
+	compatible = "amazon,imx6sl-kindle-wp63gw",  "fsl,imx6sl";
+	barebox,disable-deep-probe;
+
+	memory@80000000 {
+		reg = <0x80000000 0x10000000>;
+	};
+};
+
+&iomuxc {
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_hog>;
+
+	imx6sl-kindle-wp63gw {
+		pinctrl_hog: hoggrp {
+			fsl,pins = <
+				/* Hall sensor */
+				MX6SL_PAD_KEY_ROW7__GPIO4_IO07	0x17059
+				/* zForce touch */
+				MX6SL_PAD_I2C2_SCL__GPIO3_IO14	0x17059
+				MX6SL_PAD_I2C2_SDA__GPIO3_IO15	0x17059
+				MX6SL_PAD_KEY_ROW5__GPIO4_IO03	0x17059
+				MX6SL_PAD_KEY_ROW6__GPIO4_IO05	0x17059
+				/* EMMC_3v2_EN, EMMC_1v8_EN */
+				MX6SL_PAD_FEC_RXD0__GPIO4_IO17	0x17059
+				MX6SL_PAD_FEC_MDC__GPIO4_IO23	0x17059
+				/* WLAN pwd */
+				MX6SL_PAD_KEY_ROW2__GPIO3_IO29	0x17059
+			>;
+		};
+	};
+};
diff --git a/arch/arm/dts/imx6sl-kindle6-dp75sdi.dts b/arch/arm/dts/imx6sl-kindle6-dp75sdi.dts
new file mode 100644
index 0000000000..fbbb909077
--- /dev/null
+++ b/arch/arm/dts/imx6sl-kindle6-dp75sdi.dts
@@ -0,0 +1,55 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2025 Alexander Kurz <akurz@blala.de>
+ */
+
+/dts-v1/;
+#include "imx6sl-kindle-common.dtsi"
+#include <dt-bindings/interrupt-controller/irq.h>
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/input/input.h>
+
+/ {
+	model = "kindle6-dp75sdi";
+	compatible = "amazon,imx6sl-kindle6-dp75sdi",  "fsl,imx6sl";
+	barebox,disable-deep-probe;
+
+	memory@80000000 {
+		reg = <0x80000000 0x10000000>;
+	};
+};
+
+&iomuxc {
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_hog>;
+
+	imx6sl-kindle-dp75sdi {
+		pinctrl_hog: hoggrp {
+			fsl,pins = <
+				/* Hall sensor */
+				MX6SL_PAD_KEY_ROW7__GPIO4_IO07	0x17059
+				/* Touch reset */
+				MX6SL_PAD_KEY_ROW6__GPIO4_IO05	0x17059
+				/* EMMC_3v2_EN, EMMC_1v8_EN */
+				MX6SL_PAD_FEC_RXD0__GPIO4_IO17	0x17059
+				MX6SL_PAD_FEC_MDC__GPIO4_IO23	0x17059
+				/* WLAN pwd */
+				MX6SL_PAD_KEY_ROW2__GPIO3_IO29	0x17059
+			>;
+		};
+
+		pinctrl_i2c2: i2c2grp {
+			fsl,pins = <
+				MX6SL_PAD_I2C2_SCL__I2C2_SCL	0x4001b8b1
+				MX6SL_PAD_I2C2_SDA__I2C2_SDA	0x4001b8b1
+			>;
+		};
+	};
+};
+
+&i2c2 {
+	clock-frequency = <100000>;
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_i2c2>;
+	status = "okay";
+};
diff --git a/arch/arm/dts/imx6sl-kindle7-dp75sdi.dts b/arch/arm/dts/imx6sl-kindle7-dp75sdi.dts
new file mode 100644
index 0000000000..9765e7a0db
--- /dev/null
+++ b/arch/arm/dts/imx6sl-kindle7-dp75sdi.dts
@@ -0,0 +1,55 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2025 Alexander Kurz <akurz@blala.de>
+ */
+
+/dts-v1/;
+#include "imx6sl-kindle-common.dtsi"
+#include <dt-bindings/interrupt-controller/irq.h>
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/input/input.h>
+
+/ {
+	model = "kindle7-dp75sdi";
+	compatible = "amazon,imx6sl-kindle7-dp75sdi",  "fsl,imx6sl";
+	barebox,disable-deep-probe;
+
+	memory@80000000 {
+		reg = <0x80000000 0x20000000>;
+	};
+};
+
+&iomuxc {
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_hog>;
+
+	imx6sl-kindle-dp75sdi {
+		pinctrl_hog: hoggrp {
+			fsl,pins = <
+				/* Hall sensor */
+				MX6SL_PAD_KEY_ROW7__GPIO4_IO07	0x17059
+				/* Touch reset */
+				MX6SL_PAD_KEY_ROW6__GPIO4_IO05	0x17059
+				/* EMMC_3v2_EN, EMMC_1v8_EN */
+				MX6SL_PAD_FEC_RXD0__GPIO4_IO17	0x17059
+				MX6SL_PAD_FEC_MDC__GPIO4_IO23	0x17059
+				/* WLAN pwd */
+				MX6SL_PAD_KEY_ROW2__GPIO3_IO29	0x17059
+			>;
+		};
+
+		pinctrl_i2c2: i2c2grp {
+			fsl,pins = <
+				MX6SL_PAD_I2C2_SCL__I2C2_SCL	0x4001b8b1
+				MX6SL_PAD_I2C2_SDA__I2C2_SDA	0x4001b8b1
+			>;
+		};
+	};
+};
+
+&i2c2 {
+	clock-frequency = <100000>;
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_i2c2>;
+	status = "okay";
+};
diff --git a/arch/arm/mach-imx/Kconfig b/arch/arm/mach-imx/Kconfig
index 5f50d1a823..eb947e67fb 100644
--- a/arch/arm/mach-imx/Kconfig
+++ b/arch/arm/mach-imx/Kconfig
@@ -353,6 +353,23 @@ config MACH_ADVANTECH_ROM_742X
 	bool "Advantech ROM 742X"
 	select ARCH_IMX6
 
+config MACH_KINDLE_6_7
+	bool "i.MX6SL based Amazon Kindle generation 6 and 7"
+	select ARCH_IMX6SL
+	select SPI
+	select DRIVER_SPI_IMX
+	select I2C
+	select I2C_IMX
+	select GPIO_IMX
+	select ARM_BOARD_APPEND_ATAG
+	select ARM_LINUX
+	select OFTREE
+	select PINCTRL
+	help
+	  Say Y here if you are using the sixth or seventh generation Amazon
+	  Kindle Model No. DP75SDI (Paperwhite 2 or 3), WP63GW (Kindle 7) or
+	  NM460GZ (Kindle Voyage) based on the i.MX6SL SoC and MAX77696 PMIC.
+
 config MACH_NITROGEN6
 	bool "BoundaryDevices Nitrogen6 boards"
 	select ARCH_IMX6
diff --git a/images/Makefile.imx b/images/Makefile.imx
index 5ae14a5988..f66c0af6a4 100644
--- a/images/Makefile.imx
+++ b/images/Makefile.imx
@@ -374,6 +374,27 @@ $(call build_imx_habv4img, CONFIG_MACH_ADVANTECH_ROM_742X, start_advantech_imx6d
 
 $(call build_imx_habv4img, CONFIG_MACH_ZII_RDU2, start_imx6_zii_rdu2, zii-imx6q-rdu2/flash-header-rdu2, zii-imx6-rdu2)
 
+# ----------------------- i.MX6sl based boards --------------
+pblb-$(CONFIG_MACH_KINDLE_6_7) += start_imx6sl_kindle_wp63gw
+CFG_start_imx6sl_kindle_wp63gw.pblb.imximg = $(board)/kindle-mx6sl/flash-header-kindle-mx6sl-256m.imxcfg
+FILE_barebox-kindle-wp63gw.img = start_imx6sl_kindle_wp63gw.pblb.imximg
+image-$(CONFIG_MACH_KINDLE_6_7) += barebox-kindle-wp63gw.img
+
+pblb-$(CONFIG_MACH_KINDLE_6_7) += start_imx6sl_kindle6_dp75sdi
+CFG_start_imx6sl_kindle6_dp75sdi.pblb.imximg = $(board)/kindle-mx6sl/flash-header-kindle-mx6sl-256m.imxcfg
+FILE_barebox-kindle6-dp75sdi.img = start_imx6sl_kindle6_dp75sdi.pblb.imximg
+image-$(CONFIG_MACH_KINDLE_6_7) += barebox-kindle6-dp75sdi.img
+
+pblb-$(CONFIG_MACH_KINDLE_6_7) += start_imx6sl_kindle7_dp75sdi
+CFG_start_imx6sl_kindle7_dp75sdi.pblb.imximg = $(board)/kindle-mx6sl/flash-header-kindle-mx6sl-512m.imxcfg
+FILE_barebox-kindle7-dp75sdi.img = start_imx6sl_kindle7_dp75sdi.pblb.imximg
+image-$(CONFIG_MACH_KINDLE_6_7) += barebox-kindle7-dp75sdi.img
+
+pblb-$(CONFIG_MACH_KINDLE_6_7) += start_imx6sl_kindle_nm460gz
+CFG_start_imx6sl_kindle_nm460gz.pblb.imximg = $(board)/kindle-mx6sl/flash-header-kindle-mx6sl-512m.imxcfg
+FILE_barebox-kindle-nm460gz.img = start_imx6sl_kindle_nm460gz.pblb.imximg
+image-$(CONFIG_MACH_KINDLE_6_7) += barebox-kindle-nm460gz.img
+
 # ----------------------- i.MX6ul / i.MX6ull based boards --------------
 $(call build_imx_habv4img, CONFIG_MACH_GRINN_LITEBOARD, start_imx6ul_liteboard_256mb, grinn-liteboard/flash-header-liteboard-256mb, grinn-liteboard-256mb)
 
-- 
2.39.5

Re: [PATCH] ARM i.MX6SL: Add Kindle generation 6/7 support

[Sascha Hauer]

Hi Alexander,

On Sun, Nov 09, 2025 at 06:03:37PM +0000, Alexander Kurz wrote:
> Four Amazon Kindle 6th and 7th generation e-book readers were considered
> for this patch, referred by their models
> * DP75SDI "PINOT_WFO" (256MB) "Kindle Paperwhite 2" 6th gen
> * DP75SDI "Muscat WFO" (512MB) "Kindle Paperwhite 3" 7th gen
> * WP63GW "Kindle" 7th gen (512MB)
> * NM460GZ "Voyage" 7th gen (512MB)
> Kindle e-book readers from generation 6 and 7 use the i.MX6SL and an
> are shipped with a factory-adapted u-boot image. Vendor software image
> updates for these models stopped around 2021 to 2023.
> 
> Add experimental support for the kindle gen 6/7 models and make barebox
> an optional drop-in replacement for the original bootloader.
> Required PMIC settings are implemented as script.
> 
> Notable features tested on all models:
> - Support for eMMC, USB, UART, I2C and SPI.
> - LPDDR2 setup is done via DCD, the same imximage may be used
>   for USB-startup and for installation.
> - Support for vendor specific ATAGs that are required by the Kindle-System.
> - usbserial barebox console access for 10 seconds after startup.
> 
> Known issues:
> - Reset on models kindle6-dp75sdi and nm460gz does not work and triggers
>   microcode USB download boot.
> - No recovery (without soldering) like USB boot known after e.g. a failed
>   flashing attempt.
> 
> Signed-off-by: Alexander Kurz <akurz@blala.de>
> ---
>  .../boards/imx/amazon-kindle-6-7.rst          |  94 ++++++++
>  arch/arm/boards/Makefile                      |   1 +
>  arch/arm/boards/kindle-mx6sl/Makefile         |   5 +
> diff --git a/Documentation/boards/imx/amazon-kindle-6-7.rst b/Documentation/boards/imx/amazon-kindle-6-7.rst

Thanks for the good documentation, very appreciated :)

> new file mode 100644
> index 0000000000..c7a5ef9424
> +ENTRY_FUNCTION(start_imx6sl_kindle6_dp75sdi, r0, r1, r2)
> +{
> +	void *fdt;
> +
> +	imx6_cpu_lowlevel_init();
> +
> +	arm_setup_stack(0x00920000);
> +
> +	if (IS_ENABLED(CONFIG_DEBUG_LL)) {
> +		writel(0x4, 0x020e016c);
> +		imx6_uart_setup_ll();
> +	}
> +
> +	fdt = __dtb_imx6sl_kindle6_dp75sdi_start + get_runtime_offset();
> +	barebox_arm_entry(0x80000000, SZ_256M, fdt);

Does imx6ul_barebox_entry() work here instead? In that case you could
drop the memory nodes from the device trees.

> +++ b/arch/arm/dts/imx6sl-kindle-nm460gz.dts
> @@ -0,0 +1,69 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Copyright (C) 2025 Alexander Kurz <akurz@blala.de>
> + */
> +
> +/dts-v1/;
> +#include "imx6sl-kindle-common.dtsi"
> +#include <dt-bindings/interrupt-controller/irq.h>
> +#include <dt-bindings/gpio/gpio.h>
> +#include <dt-bindings/input/input.h>
> +
> +/ {
> +	model = "kindle-nm460gz";
> +	compatible = "amazon,imx6sl-kindle-nm460gz", "fsl,imx6sl";
> +	barebox,disable-deep-probe;

Is this intentional? What doesn't work with deep probe enabled?

Sascha

-- 
Pengutronix e.K.                           |                             |
Steuerwalder Str. 21                       | http://www.pengutronix.de/  |
31137 Hildesheim, Germany                  | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |

Re: [PATCH] ARM i.MX6SL: Add Kindle generation 6/7 support

[Alexander Kurz]

Hi Sascha,

On Mon, 10 Nov 2025, Sascha Hauer wrote:

> 
> Hi Alexander,
> 
> On Sun, Nov 09, 2025 at 06:03:37PM +0000, Alexander Kurz wrote:
> > Four Amazon Kindle 6th and 7th generation e-book readers were considered
...
> > diff --git a/Documentation/boards/imx/amazon-kindle-6-7.rst b/Documentation/boards/imx/amazon-kindle-6-7.rst
> 
> Thanks for the good documentation, very appreciated :)
Thanks!

> 
> > new file mode 100644
> > index 0000000000..c7a5ef9424
> > +ENTRY_FUNCTION(start_imx6sl_kindle6_dp75sdi, r0, r1, r2)
> > +{
> > +	void *fdt;
> > +
> > +	imx6_cpu_lowlevel_init();
> > +
> > +	arm_setup_stack(0x00920000);
> > +
> > +	if (IS_ENABLED(CONFIG_DEBUG_LL)) {
> > +		writel(0x4, 0x020e016c);
> > +		imx6_uart_setup_ll();
> > +	}
> > +
> > +	fdt = __dtb_imx6sl_kindle6_dp75sdi_start + get_runtime_offset();
> > +	barebox_arm_entry(0x80000000, SZ_256M, fdt);
> 
> Does imx6ul_barebox_entry() work here instead? In that case you could
> drop the memory nodes from the device trees.
Replacing barebox_arm_entry() with imx6ul_barebox_entry() seems to work
so far (have only tested it on one device), but will this really make the 
memory nodes from the device trees obsolete as well? Some devices have 256 
while others 512MB RAM, when the amount of memory is not hardcoded, is it 
auto-determined?

> 
> > +++ b/arch/arm/dts/imx6sl-kindle-nm460gz.dts
> > @@ -0,0 +1,69 @@
> > +// SPDX-License-Identifier: GPL-2.0-or-later
> > +/*
> > + * Copyright (C) 2025 Alexander Kurz <akurz@blala.de>
> > + */
> > +
> > +/dts-v1/;
> > +#include "imx6sl-kindle-common.dtsi"
> > +#include <dt-bindings/interrupt-controller/irq.h>
> > +#include <dt-bindings/gpio/gpio.h>
> > +#include <dt-bindings/input/input.h>
> > +
> > +/ {
> > +	model = "kindle-nm460gz";
> > +	compatible = "amazon,imx6sl-kindle-nm460gz", "fsl,imx6sl";
> > +	barebox,disable-deep-probe;
> 
> Is this intentional? What doesn't work with deep probe enabled?
With barebox,deep-probe mmc1 will not be available when kindle_rev_init()
is called at late_initcall(kindle_mx6sl_late_init).
This way, the required ATAGs will be missing.
Will deep-probe influence device_initcall(kindle6_device_init)?

> 
> Sascha
> 
Cheers, Alexander

Re: [PATCH] ARM i.MX6SL: Add Kindle generation 6/7 support

[Sascha Hauer]

On Tue, Nov 11, 2025 at 07:32:13AM +0000, Alexander Kurz wrote:
> Hi Sascha,
> 
> On Mon, 10 Nov 2025, Sascha Hauer wrote:
> 
> > 
> > Hi Alexander,
> > 
> > On Sun, Nov 09, 2025 at 06:03:37PM +0000, Alexander Kurz wrote:
> > > Four Amazon Kindle 6th and 7th generation e-book readers were considered
> ...
> > > diff --git a/Documentation/boards/imx/amazon-kindle-6-7.rst b/Documentation/boards/imx/amazon-kindle-6-7.rst
> > 
> > Thanks for the good documentation, very appreciated :)
> Thanks!
> 
> > 
> > > new file mode 100644
> > > index 0000000000..c7a5ef9424
> > > +ENTRY_FUNCTION(start_imx6sl_kindle6_dp75sdi, r0, r1, r2)
> > > +{
> > > +	void *fdt;
> > > +
> > > +	imx6_cpu_lowlevel_init();
> > > +
> > > +	arm_setup_stack(0x00920000);
> > > +
> > > +	if (IS_ENABLED(CONFIG_DEBUG_LL)) {
> > > +		writel(0x4, 0x020e016c);
> > > +		imx6_uart_setup_ll();
> > > +	}
> > > +
> > > +	fdt = __dtb_imx6sl_kindle6_dp75sdi_start + get_runtime_offset();
> > > +	barebox_arm_entry(0x80000000, SZ_256M, fdt);
> > 
> > Does imx6ul_barebox_entry() work here instead? In that case you could
> > drop the memory nodes from the device trees.
> Replacing barebox_arm_entry() with imx6ul_barebox_entry() seems to work
> so far (have only tested it on one device), but will this really make the 
> memory nodes from the device trees obsolete as well? Some devices have 256 
> while others 512MB RAM, when the amount of memory is not hardcoded, is it 
> auto-determined?

Yes, the memory nodes will be autogenerated from the configuration read
back from the DRAM controller.

> 
> > 
> > > +++ b/arch/arm/dts/imx6sl-kindle-nm460gz.dts
> > > @@ -0,0 +1,69 @@
> > > +// SPDX-License-Identifier: GPL-2.0-or-later
> > > +/*
> > > + * Copyright (C) 2025 Alexander Kurz <akurz@blala.de>
> > > + */
> > > +
> > > +/dts-v1/;
> > > +#include "imx6sl-kindle-common.dtsi"
> > > +#include <dt-bindings/interrupt-controller/irq.h>
> > > +#include <dt-bindings/gpio/gpio.h>
> > > +#include <dt-bindings/input/input.h>
> > > +
> > > +/ {
> > > +	model = "kindle-nm460gz";
> > > +	compatible = "amazon,imx6sl-kindle-nm460gz", "fsl,imx6sl";
> > > +	barebox,disable-deep-probe;
> > 
> > Is this intentional? What doesn't work with deep probe enabled?
> With barebox,deep-probe mmc1 will not be available when kindle_rev_init()
> is called at late_initcall(kindle_mx6sl_late_init).
> This way, the required ATAGs will be missing.
> Will deep-probe influence device_initcall(kindle6_device_init)?

deep probe will probe devices on demand for you. What's left to do for
you is to say that you need the mmc1 device by doing a:

of_device_ensure_probed_by_alias("mmc1");

This will handle the dependencies like probing regulators or clocks
regardless of the initcall level you are in.

You also have this in your patch:

+       /* Probe the eMMC to allow reading the board serial and revision */
+       dev = get_device_by_name("mmc1");
+       if (dev)
+               dev_set_param(dev, "probe", "1");

which can be replaced by a:

device_detect_by_name("mmc1");

The different initcall levels in your board code shouldn't be necessary
anmore with this.

Sascha

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