6be2305da8
Changelog: * https://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.1.5 Signed-off-by: Jonas Gorski <jogo@openwrt.org> SVN-Revision: 46598
262 lines
6.7 KiB
Diff
262 lines
6.7 KiB
Diff
From bec69bb8e85151729014d859106dcc3fe652b1d4 Mon Sep 17 00:00:00 2001
|
|
From: Boris BREZILLON <boris.brezillon@free-electrons.com>
|
|
Date: Mon, 28 Jul 2014 14:45:40 +0200
|
|
Subject: [PATCH] mtd: nand: Add page status table (pst)
|
|
|
|
Page status table is an byte array storing pages status.
|
|
It defines 3 status:
|
|
- unknown: the page has not been read yet and we do not know its current
|
|
state
|
|
- empty: the page contains only FFs
|
|
- filled: the page has been filled with data
|
|
|
|
Care must be taken: an empty page does not mean it can be written, because
|
|
it might have already been written with only FFs.
|
|
|
|
These page status are useful to check wether the controller should try to
|
|
correct errors (using ECC) or a derandomize data (using a randomizer
|
|
block).
|
|
|
|
Signed-off-by: Boris BREZILLON <boris.brezillon@free-electrons.com>
|
|
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
|
|
---
|
|
drivers/mtd/nand/nand_base.c | 154 +++++++++++++++++++++++++++++++++++++++++++
|
|
include/linux/mtd/nand.h | 21 ++++++
|
|
2 files changed, 175 insertions(+)
|
|
|
|
--- a/drivers/mtd/nand/nand_base.c
|
|
+++ b/drivers/mtd/nand/nand_base.c
|
|
@@ -1102,6 +1102,138 @@ out:
|
|
EXPORT_SYMBOL(nand_lock);
|
|
|
|
/**
|
|
+ * nand_page_is_empty - check wether a NAND page contains only FFs
|
|
+ * @mtd: mtd info
|
|
+ * @data: data buffer
|
|
+ * @oob: oob buffer
|
|
+ *
|
|
+ * Reads the data stored in the databuf buffer and check if it contains only
|
|
+ * FFs.
|
|
+ *
|
|
+ * Return true if it does else return false.
|
|
+ */
|
|
+bool nand_page_is_empty(struct mtd_info *mtd, void *data, void *oob)
|
|
+{
|
|
+ u8 *buf;
|
|
+ int length;
|
|
+ u32 pattern = 0xffffffff;
|
|
+ int bitflips = 0;
|
|
+ int cnt;
|
|
+
|
|
+ buf = data;
|
|
+ length = mtd->writesize;
|
|
+ while (length) {
|
|
+ cnt = length < sizeof(pattern) ? length : sizeof(pattern);
|
|
+ if (memcmp(&pattern, buf, cnt)) {
|
|
+ int i;
|
|
+ for (i = 0; i < cnt * BITS_PER_BYTE; i++) {
|
|
+ if (!(buf[i / BITS_PER_BYTE] &
|
|
+ (1 << (i % BITS_PER_BYTE)))) {
|
|
+ bitflips++;
|
|
+ if (bitflips > mtd->ecc_strength)
|
|
+ return false;
|
|
+ }
|
|
+ }
|
|
+ }
|
|
+
|
|
+ buf += sizeof(pattern);
|
|
+ length -= sizeof(pattern);
|
|
+ }
|
|
+
|
|
+ buf = oob;
|
|
+ length = mtd->oobsize;
|
|
+ while (length) {
|
|
+ cnt = length < sizeof(pattern) ? length : sizeof(pattern);
|
|
+ if (memcmp(&pattern, buf, cnt)) {
|
|
+ int i;
|
|
+ for (i = 0; i < cnt * BITS_PER_BYTE; i++) {
|
|
+ if (!(buf[i / BITS_PER_BYTE] &
|
|
+ (1 << (i % BITS_PER_BYTE)))) {
|
|
+ bitflips++;
|
|
+ if (bitflips > mtd->ecc_strength)
|
|
+ return false;
|
|
+ }
|
|
+ }
|
|
+ }
|
|
+
|
|
+ buf += sizeof(pattern);
|
|
+ length -= sizeof(pattern);
|
|
+ }
|
|
+
|
|
+ return true;
|
|
+}
|
|
+EXPORT_SYMBOL(nand_page_is_empty);
|
|
+
|
|
+/**
|
|
+ * nand_page_get_status - retrieve page status from the page status table (pst)
|
|
+ * @mtd: mtd info
|
|
+ * @page: page you want to get status on
|
|
+ *
|
|
+ * Return the page status.
|
|
+ */
|
|
+int nand_page_get_status(struct mtd_info *mtd, int page)
|
|
+{
|
|
+ struct nand_chip *chip = mtd->priv;
|
|
+ u8 shift = (page % 4) * 2;
|
|
+ uint64_t offset = page / 4;
|
|
+ int ret = NAND_PAGE_STATUS_UNKNOWN;
|
|
+
|
|
+ if (chip->pst)
|
|
+ ret = (chip->pst[offset] >> shift) & 0x3;
|
|
+
|
|
+ return ret;
|
|
+}
|
|
+EXPORT_SYMBOL(nand_page_get_status);
|
|
+
|
|
+/**
|
|
+ * nand_page_set_status - assign page status from in the page status table
|
|
+ * @mtd: mtd info
|
|
+ * @page: page you want to get status on
|
|
+ * @status: new status to assign
|
|
+ */
|
|
+void nand_page_set_status(struct mtd_info *mtd, int page,
|
|
+ enum nand_page_status status)
|
|
+{
|
|
+ struct nand_chip *chip = mtd->priv;
|
|
+ u8 shift;
|
|
+ uint64_t offset;
|
|
+
|
|
+ if (!chip->pst)
|
|
+ return;
|
|
+
|
|
+ shift = (page % 4) * 2;
|
|
+ offset = page / 4;
|
|
+ chip->pst[offset] &= ~(0x3 << shift);
|
|
+ chip->pst[offset] |= (status & 0x3) << shift;
|
|
+}
|
|
+EXPORT_SYMBOL(nand_page_set_status);
|
|
+
|
|
+/**
|
|
+ * nand_pst_create - create a page status table
|
|
+ * @mtd: mtd info
|
|
+ *
|
|
+ * Allocate a page status table and assign it to the mtd device.
|
|
+ *
|
|
+ * Returns 0 in case of success or -ERRNO in case of error.
|
|
+ */
|
|
+int nand_pst_create(struct mtd_info *mtd)
|
|
+{
|
|
+ struct nand_chip *chip = mtd->priv;
|
|
+
|
|
+ if (chip->pst)
|
|
+ return 0;
|
|
+
|
|
+ chip->pst = kzalloc(mtd->size >>
|
|
+ (chip->page_shift + mtd->subpage_sft + 2),
|
|
+ GFP_KERNEL);
|
|
+ if (!chip->pst)
|
|
+ return -ENOMEM;
|
|
+
|
|
+ return 0;
|
|
+}
|
|
+EXPORT_SYMBOL(nand_pst_create);
|
|
+
|
|
+/**
|
|
* nand_read_page_raw - [INTERN] read raw page data without ecc
|
|
* @mtd: mtd info structure
|
|
* @chip: nand chip info structure
|
|
@@ -2539,6 +2671,7 @@ static int nand_do_write_ops(struct mtd_
|
|
uint8_t *wbuf = buf;
|
|
int use_bufpoi;
|
|
int part_pagewr = (column || writelen < (mtd->writesize - 1));
|
|
+ int subpage;
|
|
|
|
if (part_pagewr)
|
|
use_bufpoi = 1;
|
|
@@ -2574,6 +2707,14 @@ static int nand_do_write_ops(struct mtd_
|
|
if (ret)
|
|
break;
|
|
|
|
+ for (subpage = column / chip->subpagesize;
|
|
+ subpage < (column + writelen) / chip->subpagesize;
|
|
+ subpage++)
|
|
+ nand_page_set_status(mtd,
|
|
+ (page << mtd->subpage_sft) +
|
|
+ subpage,
|
|
+ NAND_PAGE_FILLED);
|
|
+
|
|
writelen -= bytes;
|
|
if (!writelen)
|
|
break;
|
|
@@ -2979,6 +3120,7 @@ int nand_erase_nand(struct mtd_info *mtd
|
|
int page, status, pages_per_block, ret, chipnr;
|
|
struct nand_chip *chip = mtd->priv;
|
|
loff_t len;
|
|
+ int i;
|
|
|
|
pr_debug("%s: start = 0x%012llx, len = %llu\n",
|
|
__func__, (unsigned long long)instr->addr,
|
|
@@ -3051,6 +3193,18 @@ int nand_erase_nand(struct mtd_info *mtd
|
|
goto erase_exit;
|
|
}
|
|
|
|
+ for (i = 0; i < pages_per_block; i++) {
|
|
+ int subpage;
|
|
+ for (subpage = 0;
|
|
+ subpage < 1 << mtd->subpage_sft;
|
|
+ subpage++) {
|
|
+ nand_page_set_status(mtd,
|
|
+ ((page + i) << mtd->subpage_sft) +
|
|
+ subpage,
|
|
+ NAND_PAGE_EMPTY);
|
|
+ }
|
|
+ }
|
|
+
|
|
/* Increment page address and decrement length */
|
|
len -= (1ULL << chip->phys_erase_shift);
|
|
page += pages_per_block;
|
|
--- a/include/linux/mtd/nand.h
|
|
+++ b/include/linux/mtd/nand.h
|
|
@@ -521,6 +521,24 @@ struct nand_ecc_ctrl {
|
|
int page);
|
|
};
|
|
|
|
+/*
|
|
+ * Constants for page status
|
|
+ */
|
|
+enum nand_page_status {
|
|
+ NAND_PAGE_STATUS_UNKNOWN,
|
|
+ NAND_PAGE_EMPTY,
|
|
+ NAND_PAGE_FILLED,
|
|
+};
|
|
+
|
|
+bool nand_page_is_empty(struct mtd_info *mtd, void *data, void *oob);
|
|
+
|
|
+int nand_page_get_status(struct mtd_info *mtd, int page);
|
|
+
|
|
+void nand_page_set_status(struct mtd_info *mtd, int page,
|
|
+ enum nand_page_status status);
|
|
+
|
|
+int nand_pst_create(struct mtd_info *mtd);
|
|
+
|
|
/**
|
|
* struct nand_buffers - buffer structure for read/write
|
|
* @ecccalc: buffer pointer for calculated ECC, size is oobsize.
|
|
@@ -630,6 +648,7 @@ struct nand_buffers {
|
|
* @bbt_md: [REPLACEABLE] bad block table mirror descriptor
|
|
* @badblock_pattern: [REPLACEABLE] bad block scan pattern used for initial
|
|
* bad block scan.
|
|
+ * @pst: [INTERN] page status table
|
|
* @controller: [REPLACEABLE] a pointer to a hardware controller
|
|
* structure which is shared among multiple independent
|
|
* devices.
|
|
@@ -718,6 +737,8 @@ struct nand_chip {
|
|
|
|
struct nand_bbt_descr *badblock_pattern;
|
|
|
|
+ uint8_t *pst;
|
|
+
|
|
struct list_head partitions;
|
|
struct mutex part_lock;
|
|
|