[PATCH v2 2/2] mci: implement command to switch a mmc device to enhanced mode

["Uwe Kleine-König" <u.kleine-koenig@pengutronix.de>]

The command structure allows adding more subcommands and is designed to
match the Linux program mmc from the mmc-utils. So later more commands
can easily be added if need be.

Compared to mmc-utils'

	mmc enh_area set <-y|-n|-c> <start KiB> <length KiB> <device>

the command that is implemented here (

	mmc enh_area setmax <-y|-n|-c> <device>

) is easier to use (because you don't have to check the maximal allowed
size by reading some registers and calculate the available size from
them (which then must be calculated back to register values by the mmc
command)) but less flexible as it doesn't allow all the crazy
possibilities specified in the eMMC standard but just creates an
enhanced area with maximal size.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
---
 commands/Kconfig  |   5 ++
 commands/Makefile |   1 +
 commands/mmc.c    | 171 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 include/mci.h     |   7 +++
 4 files changed, 184 insertions(+)
 create mode 100644 commands/mmc.c

diff --git a/commands/Kconfig b/commands/Kconfig
index ae2dc4b0947b..1b29365a06f2 100644
--- a/commands/Kconfig
+++ b/commands/Kconfig
@@ -238,6 +238,11 @@ config CMD_VERSION
 
 	  barebox 2014.05.0-00142-gb289373 #177 Mon May 12 20:35:55 CEST 2014
 
+config CMD_MMC
+	tristate
+	prompt "mmc command allowing to set enhanced area"
+	depends on MCI
+
 config CMD_MMC_EXTCSD
 	tristate
 	prompt "read/write eMMC ext. CSD register"
diff --git a/commands/Makefile b/commands/Makefile
index 37486dceb181..bcd0665cfe88 100644
--- a/commands/Makefile
+++ b/commands/Makefile
@@ -120,6 +120,7 @@ obj-$(CONFIG_CMD_DHCP)		+= dhcp.o
 obj-$(CONFIG_CMD_BOOTCHOOSER)	+= bootchooser.o
 obj-$(CONFIG_CMD_DHRYSTONE)	+= dhrystone.o
 obj-$(CONFIG_CMD_SPD_DECODE)	+= spd_decode.o
+obj-$(CONFIG_CMD_MMC)		+= mmc.o
 obj-$(CONFIG_CMD_MMC_EXTCSD)	+= mmc_extcsd.o
 obj-$(CONFIG_CMD_NAND_BITFLIP)	+= nand-bitflip.o
 obj-$(CONFIG_CMD_SEED)		+= seed.o
diff --git a/commands/mmc.c b/commands/mmc.c
new file mode 100644
index 000000000000..2f5c7ad69a37
--- /dev/null
+++ b/commands/mmc.c
@@ -0,0 +1,171 @@
+#include <command.h>
+#include <mci.h>
+#include <stdio.h>
+#include <string.h>
+
+/* enh_area setmax <-y|-n|-c> /dev/mmcX */
+static int do_mmc_enh_area(int argc, char *argv[])
+{
+	char *devname;
+	struct mci *mci;
+	u8 *ext_csd;
+	int set_completed = 0;
+	int ret;
+
+	if (argc != 4 || strcmp(argv[1], "setmax") ||
+	    argv[2][0] != '-' ||
+	    (argv[2][1] != 'y' && argv[2][1] != 'n' && argv[2][1] != 'c')) {
+		printf("Usage: mmc enh_area setmax <-y|-n|-c> /dev/mmcX\n");
+		return 1;
+	}
+
+	if (argv[2][1] == 'y')
+		set_completed = 1;
+
+	devname = argv[3];
+	if (!strncmp(devname, "/dev/", 5))
+		devname += 5;
+
+	mci = mci_get_device_by_name(devname);
+	if (!mci) {
+		printf("Failure to open %s as mci device\n", devname);
+		return -ENOENT;
+	}
+	/* get extcsd */
+	ext_csd = xmalloc(512);
+
+	ret = mci_send_ext_csd(mci, ext_csd);
+	if (ret) {
+		printf("Failure to read EXT_CSD register\n");
+		goto error;
+	}
+
+	if (!(ext_csd[EXT_CSD_PARTITIONING_SUPPORT] & EXT_CSD_ENH_ATTRIBUTE_EN_MASK)) {
+		printf("Device doesn't support enhanced area\n");
+		ret = -EIO;
+		goto error;
+	}
+
+	if (ext_csd[EXT_CSD_PARTITION_SETTING_COMPLETED]) {
+		printf("Partitioning already finalized\n");
+		ret = -EIO;
+		goto error;
+	}
+
+	ret = mci_switch(mci, EXT_CSD_ERASE_GROUP_DEF, 1);
+	if (ret) {
+		printf("Failure to write to EXT_CSD_ERASE_GROUP_DEF\n");
+		goto error;
+	}
+
+	ret = mci_switch(mci, EXT_CSD_ENH_START_ADDR, 0);
+	if (ret) {
+		printf("Failure to write to EXT_CSD_ENH_START_ADDR[0]\n");
+		goto error;
+	}
+
+	ret = mci_switch(mci, EXT_CSD_ENH_START_ADDR + 1, 0);
+	if (ret) {
+		printf("Failure to write to EXT_CSD_ENH_START_ADDR[1]\n");
+		goto error;
+	}
+
+	ret = mci_switch(mci, EXT_CSD_ENH_START_ADDR + 2, 0);
+	if (ret) {
+		printf("Failure to write to EXT_CSD_ENH_START_ADDR[2]\n");
+		goto error;
+	}
+
+	ret = mci_switch(mci, EXT_CSD_ENH_START_ADDR + 3, 0);
+	if (ret) {
+		printf("Failure to write to EXT_CSD_ENH_START_ADDR[3]\n");
+		goto error;
+	}
+
+	ret = mci_switch(mci, EXT_CSD_ENH_SIZE_MULT, ext_csd[EXT_CSD_MAX_ENH_SIZE_MULT]);
+	if (ret) {
+		printf("Failure to write to EXT_CSD_ENH_SIZE_MULT[0]\n");
+		goto error;
+	}
+
+	ret = mci_switch(mci, EXT_CSD_ENH_SIZE_MULT + 1, ext_csd[EXT_CSD_MAX_ENH_SIZE_MULT + 1]);
+	if (ret) {
+		printf("Failure to write to EXT_CSD_ENH_SIZE_MULT[1]\n");
+		goto error;
+	}
+
+	ret = mci_switch(mci, EXT_CSD_ENH_SIZE_MULT + 2, ext_csd[EXT_CSD_MAX_ENH_SIZE_MULT + 2]);
+	if (ret) {
+		printf("Failure to write to EXT_CSD_ENH_SIZE_MULT[2]\n");
+		goto error;
+	}
+
+	ret = mci_switch(mci, EXT_CSD_PARTITIONS_ATTRIBUTE, ext_csd[EXT_CSD_PARTITIONS_ATTRIBUTE] | EXT_CSD_ENH_USR_MASK);
+	if (ret) {
+		printf("Failure to write to EXT_CSD_PARTITIONS_ATTRIBUTE\n");
+		goto error;
+	}
+
+	if (set_completed) {
+		ret = mci_switch(mci, EXT_CSD_PARTITION_SETTING_COMPLETED, 1);
+		if (ret) {
+			printf("Failure to write to EXT_CSD_PARTITION_SETTING_COMPLETED\n");
+error:
+			free(ext_csd);
+		} else {
+			printf("Now power cycle the device to let it reconfigure itself.\n");
+		}
+	}
+
+	return ret;
+}
+
+static struct {
+	const char *cmd;
+	int (*func)(int argc, char *argv[]);
+} mmc_subcmds[] = {
+	{
+		.cmd = "enh_area",
+		.func = do_mmc_enh_area,
+	}
+};
+
+static int do_mmc(int argc, char *argv[])
+{
+	size_t i, subcmdlen;
+	int (*func)(int argc, char *argv[]) = NULL;
+
+	if (argc < 2) {
+		printf("mmc: required subcommand missing\n");
+		return 1;
+	}
+
+	subcmdlen = strlen(argv[1]);
+	for (i = 0; i < ARRAY_SIZE(mmc_subcmds); ++i) {
+		if (strncmp(mmc_subcmds[i].cmd, argv[1], subcmdlen) == 0) {
+			if (subcmdlen == strlen(mmc_subcmds[i].cmd)) {
+				/* exact match */
+				func = mmc_subcmds[i].func;
+				break;
+			} else if (func) {
+				printf("mmc: ambiguously abbreviated subcommand");
+				return 1;
+			} else {
+				func = mmc_subcmds[i].func;
+			}
+		}
+	}
+
+	if (func) {
+		int ret = func(argc - 1, argv + 1);
+		return ret < 0;
+	} else {
+		printf("mmc: subcommand \"%s\" not found\n", argv[1]);
+		return 1;
+	}
+}
+
+BAREBOX_CMD_START(mmc)
+	.cmd = do_mmc,
+	BAREBOX_CMD_OPTS("enh_area setmax <-y|-n|-c> /dev/mmcX")
+BAREBOX_CMD_END
diff --git a/include/mci.h b/include/mci.h
index 827eecd39f8d..779da9c156db 100644
--- a/include/mci.h
+++ b/include/mci.h
@@ -304,6 +304,13 @@
 #define EXT_CSD_CARD_TYPE_SDR_1_2V	(1<<5)	/* Card can run at 200MHz */
 						/* SDR mode @1.2V I/O */
 
+/* register PARTITIONS_ATTRIBUTE [156] */
+#define EXT_CSD_ENH_USR_MASK		(1 << 0)
+
+/* register PARTITIONING_SUPPORT [160] */
+#define EXT_CSD_ENH_ATTRIBUTE_EN_MASK	(1 << 0)
+
+/* register BUS_WIDTH [183], field Bus Mode Selection [4:0] */
 #define EXT_CSD_BUS_WIDTH_1	0	/* Card is in 1 bit mode */
 #define EXT_CSD_BUS_WIDTH_4	1	/* Card is in 4 bit mode */
 #define EXT_CSD_BUS_WIDTH_8	2	/* Card is in 8 bit mode */
-- 
2.11.0


_______________________________________________
barebox mailing list
barebox@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/barebox