mmc-util: add the method to enable the bkops

This patch added the method to enable the bkops. In ext_csd register, BKOPS_EN bit is one-time programable. So if you want to use the bkops, use the this command.

<usage>
#mmc bkops enable /dev/mmcblk0

Signed-off-by Jaehoon Chung <[email protected]>

Signed-off-by Kyungmin Park <[email protected]>

Reviewd-by Venkatraman S <[email protected]>

---
 mmc.c      |    5 +++++
 mmc.h      |    7 +++++++
 mmc_cmds.c |   39 +++++++++++++++++++++++++++++++++++++++
 mmc_cmds.h |    1 +
 4 files changed, 52 insertions(+), 0 deletions(-)

mmc.c +5 -0

index 379d667..d5ef2bb 100644
@@ -75,6 +75,11 @@ static struct Command commands[] = {
 		"Enable the boot partition for the <device>.\nTo receive acknowledgment of boot from the card set <send_ack>\nto 1, else set it to 0.",
 	  NULL
 	},
+	{ do_write_bkops_en, -1,
+	  "bkops enable", "<device>\n"
+		"Enable the eMMC BKOPS feature on <device>.",
+	  NULL
+	},
 	{ 0, 0, 0, 0 }
 };
 

mmc.h +7 -0

index 0a521a8..3d77b38 100644
@@ -31,12 +31,14 @@
  */
 #define EXT_CSD_S_CMD_SET		504
 #define EXT_CSD_HPI_FEATURE		503
+#define EXT_CSD_BKOPS_SUPPORT		502	/* RO */
 #define EXT_CSD_BOOT_INFO		228	/* R/W */
 #define EXT_CSD_PART_SWITCH_TIME	199
 #define EXT_CSD_BOOT_CFG		179
 #define EXT_CSD_PART_CONFIG		179
 #define EXT_CSD_BOOT_WP			173
 #define EXT_CSD_WR_REL_PARAM		166
+#define EXT_CSD_BKOPS_EN		163	/* R/W */
 #define EXT_CSD_NATIVE_SECTOR_SIZE	63 /* R */
 #define EXT_CSD_USE_NATIVE_SECTOR	62 /* R/W */
 #define EXT_CSD_DATA_SECTOR_SIZE	61 /* R */

@@ -48,6 +50,11 @@
 #define EN_REL_WR	(1<<2)
 
 /*
+ * BKOPS_EN field definition
+ */
+#define BKOPS_ENABLE	(1<<0)
+
+/*
  * EXT_CSD field definitions
  */
 #define EXT_CSD_HPI_SUPP		(1<<0)

mmc_cmds.c +39 -0

index 90619db..4c935e0 100644
@@ -280,6 +280,45 @@ int do_write_boot_en(int nargs, char **argv)
 	return ret;
 }
 
+int do_write_bkops_en(int nargs, char **argv)
+{
+	__u8 ext_csd[512], value = 0;
+	int fd, ret;
+	char *device;
+
+	CHECK(nargs != 2, "Usage: mmc bkops enable </path/to/mmcblkX>\n",
+			exit(1));
+
+	device = argv[1];
+
+	fd = open(device, O_RDWR);
+	if (fd < 0) {
+		perror("open");
+		exit(1);
+	}
+
+	ret = read_extcsd(fd, ext_csd);
+	if (ret) {
+		fprintf(stderr, "Could not read EXT_CSD from %s\n", device);
+		exit(1);
+	}
+
+	if (!(ext_csd[EXT_CSD_BKOPS_SUPPORT] & 0x1)) {
+		fprintf(stderr, "%s dosen't support BKOPS\n", device);
+		exit(1);
+	}
+
+	ret = write_extcsd_value(fd, EXT_CSD_BKOPS_EN, BKOPS_ENABLE);
+	if (ret) {
+		fprintf(stderr, "Could not write 0x%02x to "
+			"EXT_CSD[%d] in %s\n",
+			value, EXT_CSD_BKOPS_EN, device);
+		exit(1);
+	}
+
+	return ret;
+}
+
 int do_read_extcsd(int nargs, char **argv)
 {
 	__u8 ext_csd[512], ext_csd_rev, reg;

mmc_cmds.h +1 -0

index 2eb1df5..1dd4324 100644
@@ -21,3 +21,4 @@ int do_writeprotect_get(int nargs, char **argv);
 int do_writeprotect_set(int nargs, char **argv);
 int do_disable_512B_emulation(int nargs, char **argv);
 int do_write_boot_en(int nargs, char **argv);
+int do_write_bkops_en(int nargs, char **argv);

Dear Chris,

Could you merge the this at mmc-utils?
If you have any other opinion, plz let me know.

Hi,

Quoted 4 lines · Jaehoon Chung

Dear Chris,

Could you merge the this at mmc-utils?
If you have any other opinion, plz let me know.

Looks good, but I was planning to merge it at the same time as merging the kernel patch -- I think we're waiting on another revision of that?

Thanks,

- Chris.