mail archive of the barebox mailing list
 help / color / mirror / Atom feed
From: John Watts <contact@jookia.org>
To: barebox@lists.infradead.org
Cc: John Watts <contact@jookia.org>
Subject: [PATCH 5/5] ARM: novena: Use DDR3 information from SPD EEPROM
Date: Mon, 23 Jan 2023 04:51:41 +1100	[thread overview]
Message-ID: <20230122175141.119834-6-contact@jookia.org> (raw)
In-Reply-To: <20230122175141.119834-1-contact@jookia.org>

The Novena supports swappable memory which means we must query the memory
for configuration details. This patch uses values stored in the SPD EEPROM
to configure the i.MX6 memory controller.

If the SPD can't be read, the default configuration for a 4GB stick is used.

Calibration for the installed stick is run unconditionally.

Verification that this works was done by comparing MMDC registers before and
after and carefully reading other people's source code.

Signed-off-by: John Watts <contact@jookia.org>
---
 arch/arm/boards/novena/lowlevel.c | 113 ++++++++++++++++++++++++++++++
 arch/arm/mach-imx/Kconfig         |   2 +
 2 files changed, 115 insertions(+)

diff --git a/arch/arm/boards/novena/lowlevel.c b/arch/arm/boards/novena/lowlevel.c
index ee71d9edd6..753fc5dd4a 100644
--- a/arch/arm/boards/novena/lowlevel.c
+++ b/arch/arm/boards/novena/lowlevel.c
@@ -3,6 +3,8 @@
 
 #include <asm/barebox-arm.h>
 #include <common.h>
+#include <ddr_dimms.h>
+#include <ddr_spd.h>
 #include <debug_ll.h>
 #include <mach/esdctl.h>
 #include <mach/generic.h>
@@ -10,6 +12,8 @@
 #include <mach/imx6-mmdc.h>
 #include <mach/iomux-mx6.h>
 #include <mach/xload.h>
+#include <pbl.h>
+#include <pbl/i2c.h>
 #include <soc/fsl/fsl_udc.h>
 #include "ddr_regs.h"
 
@@ -18,6 +22,112 @@
 
 extern char __dtb_imx6q_novena_start[];
 
+static struct spd_eeprom spd_eeprom;
+static struct dimm_params dimm_params;
+
+#if IN_PBL
+/* I2C in the PBL requires udelay, provide our own */
+void udelay(unsigned long us)
+{
+	volatile unsigned long i;
+
+	for (i = 0; i < us * 4; i++);
+}
+#endif
+
+static struct pbl_i2c *setup_spd_i2c(void)
+{
+	void __iomem *iomuxbase = IOMEM(MX6_IOMUXC_BASE_ADDR);
+
+	imx_setup_pad(iomuxbase, MX6Q_PAD_CSI0_DAT8__I2C1_SDA);
+	imx_setup_pad(iomuxbase, MX6Q_PAD_CSI0_DAT9__I2C1_SCL);
+	return imx6_i2c_early_init(IOMEM(MX6_I2C1_BASE_ADDR));
+}
+
+static struct spd_eeprom *read_spd(void)
+{
+	struct spd_eeprom *eeprom = &spd_eeprom;
+	struct pbl_i2c *i2c = setup_spd_i2c();
+	int rc;
+
+	rc = spd_read_eeprom(i2c, 0x50, eeprom, SPD_MEMTYPE_DDR3);
+	if (rc < 0) {
+		pr_err("Couldn't read SPD EEPROM:  %x\n", rc);
+		return NULL;
+	}
+
+	rc = ddr3_spd_check(&eeprom->ddr3);
+	if (rc < 0) {
+		pr_err("Couldn't verify SPD data: %x\n", rc);
+		return NULL;
+	}
+
+	return eeprom;
+}
+
+static bool check_spd_compatible(struct spd_eeprom *eeprom)
+{
+	if (eeprom->ddr3.mem_type != 0x0b) {
+		pr_err("SPD data is not DDR3\n");
+		return false;
+	}
+
+	if ((eeprom->ddr3.bus_width & 0x1f) != 0x03) {
+		pr_err("SPD data is for a 64-bit bus\n");
+		return false;
+	}
+
+	return true;
+}
+
+static void setup_dimm_settings(struct dimm_params *params,
+				struct mx6_ddr_sysinfo *info,
+				struct mx6_ddr3_cfg *cfg)
+{
+	info->ncs = params->n_ranks;
+	info->cs_density = params->capacity / 0x8000000;
+	cfg->mem_speed = params->tckmin_x_ps;
+	cfg->density = info->cs_density / params->n_banks_per_sdram_device;
+	cfg->width = params->data_width;
+	cfg->banks = params->n_banks_per_sdram_device;
+	cfg->rowaddr = params->n_row_addr;
+	cfg->coladdr = params->n_col_addr;
+	cfg->trcd = params->trcd_ps / 10;
+	cfg->trcmin = params->trc_ps / 10;
+	cfg->trasmin = params->tras_ps / 10;
+	cfg->SRT = params->extended_op_srt;
+
+	if (params->device_width >= 16)
+		cfg->pagesz = 2;
+}
+
+static void read_dimm_settings(void)
+{
+	struct spd_eeprom *eeprom = read_spd();
+	struct dimm_params *params = &dimm_params;
+	int rc;
+
+	if (!eeprom) {
+		pr_err("Couldn't read SPD EEPROM, using default settings\n");
+		return;
+	}
+
+	if (!check_spd_compatible(eeprom)) {
+		pr_err("DIMM stick incompatible\n");
+		hang();
+	}
+
+	rc = ddr3_compute_dimm_parameters(&eeprom->ddr3, params);
+	if (rc < 0) {
+		pr_err("Couldn't compute DIMM params: %x\n", rc);
+		return;
+	}
+
+	setup_dimm_settings(params, &novena_ddr_info, &novena_ddr_cfg);
+
+	pr_info("Found DIMM: %s\n", params->mpart);
+}
+
 static bool running_from_ram(void)
 {
 	return (get_pc() >= MX6_MMDC_PORT01_BASE_ADDR);
@@ -37,6 +147,8 @@ static void setup_ram(void)
 {
 	mx6dq_dram_iocfg(64, &novena_ddr_regs, &novena_grp_regs);
 	mx6_dram_cfg(&novena_ddr_info, &novena_mmdc_calib, &novena_ddr_cfg);
+	mmdc_do_write_level_calibration();
+	mmdc_do_dqs_calibration();
 }
 
 static void load_barebox(void)
@@ -74,6 +186,7 @@ ENTRY_FUNCTION_WITHSTACK(start_imx6q_novena, STACK_TOP, r0, r1, r2)
 	if (!running_from_ram()) {
 		imx6_ungate_all_peripherals();
 		setup_uart();
+		read_dimm_settings();
 		setup_ram();
 		load_barebox();
 	} else {
diff --git a/arch/arm/mach-imx/Kconfig b/arch/arm/mach-imx/Kconfig
index 5f2d4f4123..00c9aacb2b 100644
--- a/arch/arm/mach-imx/Kconfig
+++ b/arch/arm/mach-imx/Kconfig
@@ -436,6 +436,8 @@ config MACH_NITROGEN6
 config MACH_NOVENA
 	bool "Kosagi Novena board"
 	select ARCH_IMX6
+	select DDR_SPD
+	select I2C_IMX_EARLY
 	select MCI_IMX_ESDHC_PBL
 	select REGULATOR_PFUZE
 	select USB_GADGET_DRIVER_ARC_PBL
-- 
2.39.0




  parent reply	other threads:[~2023-01-22 17:54 UTC|newest]

Thread overview: 52+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-01-22 17:51 [PATCH 0/5] Add support for the Kosagi Novena board John Watts
2023-01-22 17:51 ` [PATCH 1/5] ARM: novena: Add " John Watts
2023-01-23  9:20   ` Sascha Hauer
2023-01-22 17:51 ` [PATCH 2/5] ARM: novena: Setup RAM using static configuration John Watts
2023-01-22 17:51 ` [PATCH 3/5] ARM: novena: Require the PFUZE regulator John Watts
2023-01-22 17:51 ` [PATCH 4/5] ARM: novena: Read Ethernet MAC address from EEPROM John Watts
2023-01-23  9:33   ` Sascha Hauer
2023-01-23  9:55     ` John Watts
2023-01-24 18:35     ` John Watts
2023-01-25  8:04       ` Sascha Hauer
2023-01-25  8:11         ` John Watts
2023-01-25  8:19           ` Sascha Hauer
2023-01-25 13:31             ` John Watts
2023-01-25 13:48               ` Ahmad Fatoum
2023-01-25 14:04                 ` John Watts
2023-01-25 14:16                   ` Ahmad Fatoum
2023-01-25 14:28                     ` John Watts
2023-01-25 14:33                       ` Ahmad Fatoum
2023-01-25 14:50                         ` John Watts
2023-01-25 15:42               ` Sascha Hauer
2023-01-25 16:13                 ` John Watts
2023-01-22 17:51 ` John Watts [this message]
2023-01-22 23:20   ` [PATCH 5/5] ARM: novena: Use DDR3 information from SPD EEPROM John Watts
2023-01-25 16:42 ` [PATCH v2 0/4] Add support for the Kosagi Novena board John Watts
2023-01-25 16:42 ` [PATCH v2 1/4] ARM: novena: Add " John Watts
2023-01-25 19:33   ` Marco Felsch
2023-01-26  7:25     ` Sascha Hauer
2023-01-26  7:50     ` John Watts
2023-01-26  9:13       ` Marco Felsch
2023-01-25 16:42 ` [PATCH v2 2/4] ARM: novena: Setup RAM using static configuration John Watts
2023-01-25 19:39   ` Marco Felsch
2023-01-26  7:54     ` John Watts
2023-01-26  8:11       ` Sascha Hauer
2023-01-26  9:14         ` Marco Felsch
2023-01-25 16:42 ` [PATCH v2 3/4] ARM: novena: Read Ethernet MAC address from EEPROM John Watts
2023-01-25 20:07   ` Marco Felsch
2023-01-26  8:05     ` John Watts
2023-01-26  9:07       ` Marco Felsch
2023-01-25 16:42 ` [PATCH v2 4/4] ARM: novena: Use DDR3 information from SPD EEPROM John Watts
2023-01-29 23:27 ` [PATCH v3 0/4] Add support for the Kosagi Novena board John Watts
2023-01-29 23:27 ` [PATCH v3 1/4] ARM: novena: Add " John Watts
2023-01-30 20:13   ` Marco Felsch
2023-01-30 20:26     ` John Watts
2023-01-31  9:45       ` Marco Felsch
2023-01-29 23:27 ` [PATCH v3 2/4] ARM: novena: Setup RAM using static configuration John Watts
2023-01-29 23:27 ` [PATCH v3 3/4] ARM: novena: Read Ethernet MAC address from EEPROM John Watts
2023-01-30 20:04   ` Marco Felsch
2023-01-30 20:25     ` John Watts
2023-01-31  9:29       ` Marco Felsch
2023-01-29 23:28 ` [PATCH v3 4/4] ARM: novena: Use DDR3 information from SPD EEPROM John Watts
2023-01-30 20:18   ` Marco Felsch
2023-01-30 20:41     ` John Watts

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20230122175141.119834-6-contact@jookia.org \
    --to=contact@jookia.org \
    --cc=barebox@lists.infradead.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox