/*
* davinci_nand.c - NAND Flash Driver for DaVinci family chips
*
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/mtd/nand.h>
#include <linux/mtd/partitions.h>
#include <linux/slab.h>
#include <mach/nand.h>
#include <mach/aemif.h>
/*
* This is a device driver for the NAND flash controller found on the
* various DaVinci family chips. It handles up to four SoC chipselects,
* and some flavors of secondary chipselect (e.g. based on A12) as used
* with multichip packages.
*
* The 1-bit ECC hardware is supported, as well as the newer 4-bit ECC
* available on chips like the DM355 and OMAP-L137 and needed with the
* more error-prone MLC NAND chips.
*
* This driver assumes EM_WAIT connects all the NAND devices' RDY/nBUSY
* outputs in a "wire-AND" configuration, with no per-chip signals.
*/
struct davinci_nand_info {
struct mtd_info mtd;
struct nand_chip chip;
struct nand_ecclayout ecclayout;
struct device *dev;
struct clk *clk;
bool partitioned;
bool is_readmode;
void __iomem *base;
void __iomem *vaddr;
uint32_t ioaddr;
uint32_t current_cs;
uint32_t mask_chipsel;
uint32_t mask_ale;
uint32_t mask_cle;
uint32_t core_chipsel;
struct davinci_aemif_timing *timing;
};
static DEFINE_SPINLOCK(davinci_nand_lock);
static bool ecc4_busy;
#define to_davinci_nand(m) container_of(m, struct davinci_nand_info, mtd)
static inline unsigned int davinci_nand_readl(struct davinci_nand_info *info,
int offset)
{
return __raw_readl(info->base + offset);
}
static inline void davinci_nand_writel(struct davinci_nand_info *info,
int offset, unsigned long value)
{
__raw_writel(value, info->base + offset);
}
/*----------------------------------------------------------------------*/
/*
* Access to hardware control lines: ALE, CLE, secondary chipselect.
*/
static void nand_davinci_hwcontrol(struct mtd_info *mtd, int cmd,
unsigned int ctrl)
{
struct davinci_nand_info *info = to_davinci_nand(mtd);
uint32_t addr = info->current_cs;
struct nand_chip *nand = mtd->priv;
/* Did the control lines change? */
if (ctrl & NAND_CTRL_CHANGE) {
if ((ctrl & NAND_CTRL_CLE) == NAND_CTRL_CLE)
addr |= info->mask_cle;
else if ((ctrl & NAND_CTRL_ALE) == NAND_CTRL_ALE)
addr |= info->mask_ale;
nand->IO_ADDR_W = (void __iomem __force *)addr;
}
if (cmd != NAND_CMD_NONE)
iowrite8(cmd, nand->IO_ADDR_W);
}
static void nand_davinci_select_chip(struct mtd_info *mtd, int chip)
{
struct davinci_nand_info *info = to_davinci_nand(mtd);
uint32_t addr = info->ioaddr;
/* maybe kick in a second chipselect */
if (chip > 0)
addr |= info->mask_chipsel;
info->current_cs = addr;
info->chip.IO_ADDR_W = (void __iomem __force *)addr;
info->chip.IO_ADDR_R = info->chip.IO_ADDR_W;
}
/*----------------------------------------------------------------------*/
/*
* 1-bit hardware ECC ... context maintained for each core chipselect
*/
static inline uint32_t nand_davinci_readecc_1bit(struct mtd_info *mtd)
{
struct davinci_nand_info *info = to_davinci_nand(mtd);
return davinci_nand_readl(info, NANDF1ECC_OFFSET
+ 4 * info->core_chipsel);
}
static void nand_davinci_hwctl_1bit(struct mtd_info *mtd, int mode)
{
struct davinci_nand_info *info;
uint32_t nandcfr;
unsigned long flags;
info = to_davinci_nand(mtd);
/* Reset ECC hardware */
nand_davinci_readecc_1bit(mtd);
spin_lock_irqsave(&davinci_nand_lock, flags);
/* Restart ECC hardware */
nandcfr = davinci_nand_readl(info, NANDFCR_OFFSET);
nandcfr |= BIT(8 + info->core_chipsel);
davinci_nand_writel(info, NANDFCR_OFFSET, nandcfr);
spin_unlock_irqrestore(&davinci_nand_lock, flags);
}
/*
* Read hardware ECC value and pack into three bytes
*/
static int nand_davinci_calculate_1bit(struct mtd_info *mtd,
const u_char *dat, u_char *ecc_code)
{
unsigned int ecc_val = nand_davinci_readecc_1bit(mtd);
unsigned int ecc24 = (ecc_val & 0x0fff) | ((ecc_val & 0x0fff0000) >> 4);
/* invert so that erased block ecc is correct */
ecc24 = ~ecc24;
ecc_code[0] = (u_char)(ecc24);
ecc_code[1] = (u_char)(ecc24 >> 8);
ecc_code[2] = (u_char)(ecc24 >> 16);
return 0;
}
static int nand_davinci_correct_1bit(struct mtd_info *mtd, u_char *dat,
u_char *read_ecc, u_char *calc_ecc)
{
struct nand_chip *chip = mtd->priv;
uint32_t eccNand = read_ecc[0] | (read_ecc[1] << 8) |
(read_ecc[2] << 16);
uint32_t eccCalc = calc_ecc[0] | (calc_ecc[1] << 8) |
(calc_ecc[2] << 16);
uint32_t diff = eccCalc ^ eccNand;
if (diff) {
if ((((diff >> 12) ^ diff) & 0xfff) == 0xfff) {
/* Correctable error */
if ((diff >> (12 + 3)) < chip->ecc.size) {
dat[diff >> (12 + 3)] ^= BIT((diff >> 12) & 7);
return 1;
} else {
return -1;
}
} else if (!(diff & (diff - 1))) {
/* Single bit ECC error in the ECC itself,
* nothing to fix */
return 1;
} else {
/* Uncorrectable error */
return -1;
}
}
return 0;
}
/*----------------------------------------------------------------------*/
/*
* 4-bit hardware ECC ... context maintained over entire AEMIF
*
* This is a syndrome engine, but we avoid NAND_ECC_HW_SYNDROME
* since that forces use of a problematic "infix OOB" layout.
* Among other things, it trashes manufacturer bad block markers.
* Also, and specific to this hardware, it ECC-protects the "prepad"
* in the OOB ... while having ECC protection for parts of OOB would
* seem useful, the current MTD stack sometimes wants to update the
* OOB without recomputing ECC.
*/
static void nand_davinci_hwctl_4bit(struct mtd_info *mtd, int mode)
{
struct davinci_nand_info *info = to_davinci_nand(mtd);
unsigned long flags;
u32 val;
spin_lock_irqsave(&davinci_nand_lock, flags);
/* Start 4-bit ECC calculation for read/write */
val = davinci_nand_readl(info, NANDFCR_OFFSET);
val &= ~(0x03 << 4);
val |= (info->core_chipsel << 4) | BIT(12);
davinci_nand_writel(info, NANDFCR_OFFSET, val);
info->is_readmode = (mode == NAND_ECC_READ);
spin_unlock_irqrestore(&davinci_nand_lock, flags);
}
/* Read raw ECC code after writing to NAND. */
static void
nand_davinci_readecc_4bit(struct davinci_nand_info *info, u32 code[4])
{
const u32 mask = 0x03ff03ff;
code[0] = davinci_nand_readl(info, NAND_4BIT_ECC1_OFFSET) & mask;
code[1] = davinci_nand_readl(info, NAND_4BIT_ECC2_OFFSET) & mask;
code[2] = davinci_nand_readl(info, NAND_4BIT_ECC3_OFFSET) & mask;
code[3] = davinci_nand_readl(info, NAND_4BIT_ECC4_OFFSET) & mask;
}
/* Terminate read ECC; or return ECC (as bytes) of data written to NAND. */
static int nand_davinci_calculate_4bit(struct mtd_info *mtd,
const u_char *dat, u_char *ecc_code)
{
struct davinci_nand_info *info = to_davinci_nand(mtd);
u32 raw_ecc[4], *p;
unsigned i;
/* After a read, terminate ECC calculation by a dummy read
* of some 4-bit ECC register. ECC covers everything that
* was read; correct() just uses the hardware state, so
* ecc_code is not needed.
*/
if (info->is_readmode) {
davinci_nand_readl(info, NAND_4BIT_ECC1_OFFSET);
return 0;
}
/* Pack eight raw 10-bit ecc values into ten bytes, making
* two passes which each convert four values (in upper and
* lower halves of two 32-bit words) into five bytes. The
* ROM boot loader uses this same packing scheme.
*/
nand_davinci_readecc_4bit(info, raw_ecc);
for (i = 0, p = raw_ecc; i < 2; i++, p += 2) {
*ecc_code++ = p[0] & 0xff;
*ecc_code++ = ((p[0] >> 8) & 0x03) | ((p[0] >> 14) & 0xfc);
*ecc_code++ = ((p[0] >> 22) & 0x0f) | ((p[1] << 4) & 0xf0);
*ecc_code++ = ((p[1] >> 4) & 0x3f) | ((p[1] >> 10) & 0xc0);
*ecc_code++ = (p[1] >> 18) & 0xff;
}
return 0;
}
/* Cor
