Re: [External] : RE: [PATCH RESEND v3] mmc-utils: Add eMMC erase command support
From: kimito . sakata
Date: Wed Apr 28 2021 - 11:59:40 EST
Avri
Thanks. I will respond to you when I get the chance to go through all of it.
Kimito
On 4/27/2021 11:57 PM, Avri Altman wrote:
Hi Kimito & Bean,
From: Kimito Sakata <kimito.sakata@xxxxxxxxxx>
we have been using this erase feature for a while, but it is
still not merged into the upstream mmc-utils. Especially, for
the customer, every time when they update the mmc-utils, they
should re-install this patch again, let's try to make this
erase command upstreamed in the mmc-utils.
We need to send 3 MMC commands and it is important that they
stay in sequence. Therefore we are using MMC_IOC_MULTI_CMD.
You might also want to indicate on which platform it was tested.
Co-developed-by: Bean Huo <beanhuo@xxxxxxxxxx>
Signed-off-by: Bean Huo <beanhuo@xxxxxxxxxx>
Signed-off-by: Kimito Sakata <kimito.sakata@xxxxxxxxxx>
Reviewed-by: Kenneth Gibbons <kenny.gibbons@xxxxxxxxxx>
Changelog:
v2--v3:
1. Remove redundant ifndef
V1--V2:
1. refactor Kimito's original patch
2. change to use MMC_IOC_MULTI_CMD
3. add checkup if eMMC devie supports secure erase/trim
---
mmc.c | 8 ++++
mmc.h | 13 +++++-
mmc_cmds.c | 130
+++++++++++++++++++++++++++++++++++++++++++++++++++++
mmc_cmds.h | 1 +
4 files changed, 151 insertions(+), 1 deletion(-)
diff --git a/mmc.c b/mmc.c
index f3d724b..eb2638b 100644
--- a/mmc.c
+++ b/mmc.c
@@ -229,6 +229,14 @@ static struct Command commands[] = {
"Run Field Firmware Update with <image name> on <device>.\n",
NULL
},
+ { do_erase, -4,
+ "erase", "<type> " "<start address> " "<end address> " "<device>\n"
+ "Send Erase CMD38 with specific argument to the <device>\n\n"
+ "NOTE!: This will delete all user data in the specified region of the
device\n"
+ "<type> must be: legacy | discard | secure-erase | "
+ "secure-trim1 | secure-trim2 | trim \n",
+ NULL
+ },
{ 0, 0, 0, 0 }
};
diff --git a/mmc.h b/mmc.h
index 5754a9d..e9766d7 100644
--- a/mmc.h
+++ b/mmc.h
@@ -35,7 +35,15 @@
#define MMC_SET_WRITE_PROT 28 /* ac [31:0] data addr R1b */
#define MMC_CLEAR_WRITE_PROT 29 /* ac [31:0] data addr R1b */
#define MMC_SEND_WRITE_PROT_TYPE 31 /* ac [31:0] data addr R1 */
-
+#define MMC_ERASE_GROUP_START 35 /* ac [31:0] data addr R1 */
+#define MMC_ERASE_GROUP_END 36 /* ac [31:0] data addr R1 */
+#define MMC_ERASE 38 /* ac [31] Secure request
+ [30:16] set to 0
+ [15] Force Garbage Collect request
+ [14:2] set to 0
+ [1] Discard Enable
+ [0] Identify Write Blocks for
+ Erase (or TRIM Enable) R1b */
/*
* EXT_CSD fields
*/
@@ -62,6 +70,7 @@
#define EXT_CSD_CACHE_SIZE_2 251
#define EXT_CSD_CACHE_SIZE_1 250
#define EXT_CSD_CACHE_SIZE_0 249
+#define EXT_CSD_SEC_FEATURE_SUPPORT 231
#define EXT_CSD_BOOT_INFO 228 /* R/W */
#define EXT_CSD_HC_ERASE_GRP_SIZE 224
#define EXT_CSD_HC_WP_GRP_SIZE 221
@@ -190,6 +199,8 @@
#define EXT_CSD_REV_V4_2 2
#define EXT_CSD_REV_V4_1 1
#define EXT_CSD_REV_V4_0 0
+#define EXT_CSD_SEC_GB_CL_EN (1<<4)
+#define EXT_CSD_SEC_ER_EN (1<<0)
/* From kernel linux/mmc/core.h */
diff --git a/mmc_cmds.c b/mmc_cmds.c
index 6c24cea..24f80db 100644
--- a/mmc_cmds.c
+++ b/mmc_cmds.c
@@ -2514,6 +2514,136 @@ int do_cache_dis(int nargs, char **argv)
return do_cache_ctrl(0, nargs, argv);
}
+static int erase(int dev_fd, __u32 argin, __u32 start, __u32 end)
+{
+ int ret = 0;
+ struct mmc_ioc_multi_cmd *multi_cmd;
+
+ multi_cmd = calloc(1, sizeof(struct mmc_ioc_multi_cmd) +
+ 3 * sizeof(struct mmc_ioc_cmd));
+ if (!multi_cmd) {
+ perror("Failed to allocate memory");
+ return -ENOMEM;
+ }
I am missing reference to ERASE_GROUP_DEF.
It affects the timeout, size of erase group etc.
Don't you need to query for before starting to build the command?
+
+ multi_cmd->num_of_cmds = 3;
+ /* Set erase start address */
+ multi_cmd->cmds[0].opcode = MMC_ERASE_GROUP_START;
+ multi_cmd->cmds[0].arg = start;
+ multi_cmd->cmds[0].flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 |
MMC_CMD_AC;
+ multi_cmd->cmds[0].write_flag = 1;
+
+ /* Set erase end address */
+ multi_cmd->cmds[1].opcode = MMC_ERASE_GROUP_END;
+ multi_cmd->cmds[1].arg = end;
+ multi_cmd->cmds[1].flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 |
MMC_CMD_AC;
+ multi_cmd->cmds[1].write_flag = 1;
+
+ /* Send Erase Command */
+ multi_cmd->cmds[2].opcode = MMC_ERASE;
+ multi_cmd->cmds[2].arg = argin;
+ multi_cmd->cmds[2].cmd_timeout_ms = 300*255*255;
+ multi_cmd->cmds[2].flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B |
MMC_CMD_AC;
+ multi_cmd->cmds[2].write_flag = 1;
+
+ /* send erase cmd with multi-cmd */
+ ret = ioctl(dev_fd, MMC_IOC_MULTI_CMD, multi_cmd);
+ if (ret)
+ perror("Erase multi-cmd ioctl");
+
+ free(multi_cmd);
+ return ret;
+#endif
+}
+
+int do_erase(int nargs, char **argv)
+{
+ int dev_fd, ret;
+ char *print_str;
+ char **eptr = NULL;
+ __u8 ext_csd[512], checkup_mask = 0;
+ __u32 arg, start, end;
+
+ if (nargs != 5) {
+ fprintf(stderr, "Usage: erase <type> <start addr> <end addr>
</path/to/mmcblkX>\n");
+ exit(1);
+ }
+
+ if (strstr(argv[2], "0x") || strstr(argv[2], "0X"))
+ start = strtol(argv[2], eptr, 16);
+ else
+ start = strtol(argv[2], eptr, 10);
+
+ if (strstr(argv[3], "0x") || strstr(argv[3], "0X"))
+ end = strtol(argv[3], eptr, 16);
+ else
+ end = strtol(argv[3], eptr, 10);
You are not really using eptr - maybe just call strtol with NULL?
+
+ if (end < start) {
+ fprintf(stderr, "erase start [0x%08x] > erase end [0x%08x]\n",
+ start, end);
+ exit(1);
+ }
Start & End are in bytes for media < 2GB, and in sectors for media >=2GB.
Should also check for legal erase group restrictions.
+
+ if (strcmp(argv[1], "legacy") == 0) {
+ arg = 0x00000000;
+ print_str = "Legacy Erase";
+ } else if (strcmp(argv[1], "discard") == 0) {
+ arg = 0x00000003;
+ print_str = "Discard";
+ } else if (strcmp(argv[1], "secure-erase") == 0) {
+ print_str = "Secure Erase";
+ checkup_mask = EXT_CSD_SEC_ER_EN;
+ arg = 0x80000000;
+ } else if (strcmp(argv[1], "secure-trim1") == 0) {
+ print_str = "Secure Trim Step 1";
+ checkup_mask = EXT_CSD_SEC_ER_EN | EXT_CSD_SEC_GB_CL_EN;
+ arg = 0x80000001;
+ } else if (strcmp(argv[1], "secure-trim2") == 0) {
+ print_str = "Secure Trim Step 2";
+ checkup_mask = EXT_CSD_SEC_ER_EN | EXT_CSD_SEC_GB_CL_EN;
+ arg = 0x80008000;
+ } else if (strcmp(argv[1], "trim") == 0) {
+ print_str = "Trim";
+ checkup_mask = EXT_CSD_SEC_GB_CL_EN;
+ arg = 0x00000001;
+ } else {
+ fprintf(stderr, "Unknown erase type: %s\n", argv[1]);
+ exit(1);
+ }
Maybe use an enum for the erase type to avoid the strcmp?
Then need to update the usage message.
+
+ dev_fd = open(argv[4], O_RDWR);
+ if (dev_fd < 0) {
+ perror(argv[4]);
+ exit(1);
+ }
How do you differentiate between mmc and SD devices?
And for SD you should send different commands(35/36 vs. 32/33).
Do you intend to support SD devices as well? In another patch?
+
+ if (checkup_mask) {
+ ret = read_extcsd(dev_fd, ext_csd);
+ if (ret) {
+ fprintf(stderr, "Could not read EXT_CSD from %s\n",
+ argv[4]);
+ goto out;
+ }
+ if ((checkup_mask & ext_csd[EXT_CSD_SEC_FEATURE_SUPPORT]) !=
+ checkup_mask) {
+ fprintf(stderr, "%s is not supported in %s\n",
+ print_str, argv[4]);
+ ret = -ENOTSUP;
+ goto out;
+ }
EXT_CSD_SEC_FEATURE_SUPPORT might also contains the sanitize bit,
as well as reserved bits that you shouldn't assume they are 0, so I am not sure that this condition is correct.
The checkup only refers to bit 0 and bit 4 - maybe add a helper that accept &args and returns 0 if allowed...
Thanks,
Avri
+
+ }
+ printf("Executing %s from 0x%08x to 0x%08x\n", print_str, start, end);
+
+ ret = erase(dev_fd, arg, start, end);
+out:
+ printf(" %s %s!\n\n", print_str, ret ? "Failed" : "Succeed");
+ close(dev_fd);
+ return ret;
+}
+
+
int do_ffu(int nargs, char **argv)
{
#ifndef MMC_IOC_MULTI_CMD
diff --git a/mmc_cmds.h b/mmc_cmds.h
index 9d3246c..8331ab2 100644
--- a/mmc_cmds.h
+++ b/mmc_cmds.h
@@ -45,3 +45,4 @@ int do_ffu(int nargs, char **argv);
int do_read_scr(int argc, char **argv);
int do_read_cid(int argc, char **argv);
int do_read_csd(int argc, char **argv);
+int do_erase(int nargs, char **argv);
--
2.24.1 (Apple Git-126)