shinys000114/linux
1
0
Fork 0
mirror of https://github.com/hardkernel/linux.git synced 2026-06-06 19:08:57 +09:00
Code Issues Packages Projects Releases Wiki Activity

emmc: fix dtb backup mechanism

Browse Source 
PD#162119: emmc: fix dtb backup mechanism

Change-Id: I32ca6ffb2c01bb5f50a5af3f0b2942077da61eb8
Signed-off-by: Ruixuan Li <ruixuan.li@amlogic.com>
This commit is contained in:
Ruixuan Li
2018-03-21 17:24:25 +08:00
committed by Yixun Lan
parent 9428ea9afb
commit 2ce3582aba
1 changed files with 151 additions and 15 deletions
Download Patch File Download Diff File Expand all files Collapse all files

166
drivers/amlogic/mmc/emmc_partitions.c
View File

@@ -27,7 +27,7 @@
#include <linux/cdev.h>
#include <linux/device.h>
#include <linux/uaccess.h>
#include <linux/vmalloc.h>
#include <linux/dma-contiguous.h>
#include <linux/mmc/emmc_partitions.h>
#include <linux/amlogic/cpu_version.h>
@@ -48,6 +48,135 @@ struct class *amlmmc_dtb_class;
struct mmc_card *card_dtb;
struct mmc_partitions_fmt *pt_fmt;
/*
* 2 copies dtb were stored in dtb area.
* each is 256K.
* timestamp&checksum are in the tail.
* |<--------------DTB Area-------------->|
* |<------DTB1------->|<------DTB2------>|
*/
#define DTB_RESERVE_OFFSET (4 * SZ_1M)
#define DTB_BLK_SIZE (0x200)
#define DTB_BLK_CNT (512)
#define DTB_SIZE (DTB_BLK_CNT * DTB_BLK_SIZE)
#define DTB_COPIES (2)
#define DTB_AREA_BLK_CNT (DTB_BLK_CNT * DTB_COPIES)
/* pertransfer for internal opearations. */
#define MAX_TRANS_BLK (256)
#define MAX_TRANS_SIZE (MAX_TRANS_BLK * DTB_BLK_SIZE)
#define stamp_after(a, b) ((int)(b) - (int)(a) < 0)
struct aml_dtb_rsv {
u8 data[DTB_BLK_SIZE*DTB_BLK_CNT - 4*sizeof(unsigned int)];
unsigned int magic;
unsigned int version;
unsigned int timestamp;
unsigned int checksum;
};
struct aml_dtb_info {
unsigned int stamp[2];
u8 valid[2];
};
static struct aml_dtb_info dtb_infos = {{0, 0}, {0, 0} };
/* dtb read&write operation with backup updates */
static unsigned int _calc_dtb_checksum(struct aml_dtb_rsv *dtb)
{
int i = 0;
int size = sizeof(struct aml_dtb_rsv) - sizeof(unsigned int);
unsigned int *buffer;
unsigned int checksum = 0;
size = size >> 2;
buffer = (unsigned int *) dtb;
while (i < size)
checksum += buffer[i++];
return checksum;
}
static int _verify_dtb_checksum(struct aml_dtb_rsv *dtb)
{
unsigned int checksum;
checksum = _calc_dtb_checksum(dtb);
pr_info("calc %x, store %x\n", checksum, dtb->checksum);
return !(checksum == dtb->checksum);
}
static int _dtb_read(struct mmc_card *mmc,
int blk, unsigned char *buf)
{
int ret = 0;
unsigned char *dst = NULL;
int bit = mmc->csd.read_blkbits;
int cnt = CONFIG_DTB_SIZE >> bit;
dst = (unsigned char *)buf;
mmc_claim_host(mmc->host);
do {
ret = mmc_read_internal(mmc, blk, MAX_TRANS_BLK, dst);
if (ret) {
pr_err("%s: save dtb error", __func__);
ret = -EFAULT;
break;
}
blk += MAX_TRANS_BLK;
cnt -= MAX_TRANS_BLK;
dst = (unsigned char *)buf + MAX_TRANS_SIZE;
} while (cnt != 0);
mmc_release_host(mmc->host);
return ret;
}
static int _dtb_init(struct mmc_card *mmc)
{
int ret = 0;
struct aml_dtb_rsv *dtb;
struct aml_dtb_info *info = &dtb_infos;
int cpy = 1, valid = 0;
int bit = mmc->csd.read_blkbits;
int blk;
unsigned int pgcnt;
struct page *page = NULL;
pgcnt = PAGE_ALIGN(CONFIG_DTB_SIZE) >> PAGE_SHIFT;
page = dma_alloc_from_contiguous(NULL,
pgcnt, get_order(CONFIG_DTB_SIZE));
if (!page)
return -ENOMEM;
dtb = page_address(page);
/* read dtb2 1st, for compatibility without checksum. */
while (cpy >= 0) {
blk = ((get_reserve_partition_off_from_tbl()
+ DTB_RESERVE_OFFSET) >> bit)
+ cpy * DTB_BLK_CNT;
if (_dtb_read(mmc, blk, (unsigned char *)dtb)) {
pr_err("%s: block # %#x ERROR!\n",
__func__, blk);
} else {
ret = _verify_dtb_checksum(dtb);
if (!ret) {
info->stamp[cpy] = dtb->timestamp;
info->valid[cpy] = 1;
} else
pr_err("cpy %d is not valid\n", cpy);
}
valid += info->valid[cpy];
cpy--;
}
pr_info("total valid %d\n", valid);
dma_release_from_contiguous(NULL, page, pgcnt);
return ret;
}
int amlmmc_dtb_write(struct mmc_card *card,
unsigned char *buf, int len)
{
@@ -161,6 +290,8 @@ ssize_t mmc_dtb_read(struct file *file,
unsigned char *dtb_ptr = NULL;
ssize_t read_size = 0;
int ret = 0;
unsigned int pgcnt;
struct page *page = NULL;
if (*ppos == CONFIG_DTB_SIZE)
return 0;
@@ -170,11 +301,13 @@ ssize_t mmc_dtb_read(struct file *file,
return -EFAULT;
}
dtb_ptr = vmalloc(CONFIG_DTB_SIZE);
if (dtb_ptr == NULL) {
/* pr_err("%s: malloc buf failed", __func__);*/
pgcnt = PAGE_ALIGN(CONFIG_DTB_SIZE) >> PAGE_SHIFT;
page = dma_alloc_from_contiguous(NULL,
pgcnt, get_order(CONFIG_DTB_SIZE));
if (!page)
return -ENOMEM;
}
dtb_ptr = page_address(page);
mmc_claim_host(card_dtb->host);
ret = amlmmc_dtb_read(card_dtb,
@@ -191,9 +324,9 @@ ssize_t mmc_dtb_read(struct file *file,
read_size = count;
ret = copy_to_user(buf, (dtb_ptr + *ppos), read_size);
*ppos += read_size;
exit:
mmc_release_host(card_dtb->host);
vfree(dtb_ptr);
dma_release_from_contiguous(NULL, page, pgcnt);
return read_size;
}
@@ -204,6 +337,8 @@ ssize_t mmc_dtb_write(struct file *file,
unsigned char *dtb_ptr = NULL;
ssize_t write_size = 0;
int ret = 0;
unsigned int pgcnt = PAGE_ALIGN(CONFIG_DTB_SIZE) >> PAGE_SHIFT;
struct page *page = NULL;
if (*ppos == CONFIG_DTB_SIZE)
return 0;
@@ -212,12 +347,12 @@ ssize_t mmc_dtb_write(struct file *file,
pr_err("%s: out of space!", __func__);
return -EFAULT;
}
dtb_ptr = vmalloc(CONFIG_DTB_SIZE);
if (dtb_ptr == NULL) {
/* pr_err("%s: malloc buf failed", __func__);*/
page = dma_alloc_from_contiguous(NULL,
pgcnt, get_order(CONFIG_DTB_SIZE));
if (!page)
return -ENOMEM;
}
mmc_claim_host(card_dtb->host);
dtb_ptr = page_address(page);
if ((*ppos + count) > CONFIG_DTB_SIZE)
write_size = CONFIG_DTB_SIZE - *ppos;
@@ -236,9 +371,7 @@ ssize_t mmc_dtb_write(struct file *file,
*ppos += write_size;
exit:
mmc_release_host(card_dtb->host);
/* kfree(dtb_ptr); */
vfree(dtb_ptr);
dma_release_from_contiguous(NULL, page, pgcnt);
return write_size;
}
@@ -260,6 +393,9 @@ int amlmmc_dtb_init(struct mmc_card *card)
card_dtb = card;
pr_info("%s: register dtb chardev", __func__);
_dtb_init(card);
ret = alloc_chrdev_region(&amlmmc_dtb_no, 0, 1, DTB_NAME);
if (ret < 0) {
pr_err("alloc dtb dev_t no failed");