[U-Boot-Users] [PATCH 4/6] cfi_flash: Introduce read and write accessors

Haavard Skinnemoen
2007-12-11T15:28:18Z

Introduce flash_read{8,16,32,64) and flash_write{8,16,32,64} and use
them to access the flash memory. This makes it clearer when the flash
is actually being accessed; merely dereferencing a volatile pointer
looks just like any other kind of access.

Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
---
drivers/mtd/cfi_flash.c | 203 +++++++++++++++++++++++++++++------------------
1 files changed, 125 insertions(+), 78 deletions(-)

diff --git a/drivers/mtd/cfi_flash.c b/drivers/mtd/cfi_flash.c
index a89fcae..70a626a 100644
--- a/drivers/mtd/cfi_flash.c
+++ b/drivers/mtd/cfi_flash.c
@@ -149,13 +149,6 @@ typedef union {
unsigned long long ll;
} cfiword_t;

-typedef union {
- volatile unsigned char *cp;
- volatile unsigned short *wp;
- volatile unsigned long *lp;
- volatile unsigned long long *llp;
-} cfiptr_t;
-
#define NUM_ERASE_REGIONS 4 /* max. number of erase regions */

static uint flash_offset_cfi[2] = { FLASH_OFFSET_CFI, FLASH_OFFSET_CFI_ALT };
@@ -178,6 +171,46 @@ flash_info_t flash_info[CFG_MAX_FLASH_BANKS]; /* FLASH chips info */

typedef unsigned long flash_sect_t;

+static void flash_write8(u8 value, void *addr)
+{
+ *(volatile u8 *)addr = value;
+}
+
+static void flash_write16(u16 value, void *addr)
+{
+ *(volatile u16 *)addr = value;
+}
+
+static void flash_write32(u32 value, void *addr)
+{
+ *(volatile u32 *)addr = value;
+}
+
+static void flash_write64(u64 value, void *addr)
+{
+ *(volatile u64 *)addr = value;
+}
+
+static u8 flash_read8(void *addr)
+{
+ return *(volatile u8 *)addr;
+}
+
+static u16 flash_read16(void *addr)
+{
+ return *(volatile u16 *)addr;
+}
+
+static u32 flash_read32(void *addr)
+{
+ return *(volatile u32 *)addr;
+}
+
+static u64 flash_read64(void *addr)
+{
+ return *(volatile u64 *)addr;
+}
+
/*-----------------------------------------------------------------------
*/
#if defined(CFG_ENV_IS_IN_FLASH) || defined(CFG_ENV_ADDR_REDUND) || (CFG_MONITOR_BASE >= CFG_FLASH_BASE)
@@ -238,21 +271,21 @@ static void print_longlong (char *str, unsigned long long data)

static void flash_printqry (flash_info_t * info, flash_sect_t sect)
{
- cfiptr_t cptr;
+ void *addr;
int x, y;

for (x = 0; x < 0x40; x += 16U / info->portwidth) {
- cptr.cp =
- flash_make_addr (info, sect,
- x + FLASH_OFFSET_CFI_RESP);
- debug ("%p : ", cptr.cp);
+ addr = flash_make_addr (info, sect,
+ x + FLASH_OFFSET_CFI_RESP);
+ debug ("%p : ", addr);
for (y = 0; y < 16; y++) {
- debug ("%2.2x ", cptr.cp[y]);
+ debug ("%2.2x ", flash_read8(addr + y));
}
debug (" ");
for (y = 0; y < 16; y++) {
- if (cptr.cp[y] >= 0x20 && cptr.cp[y] <= 0x7e) {
- debug ("%c", cptr.cp[y]);
+ unsigned char c = flash_read8(addr + y);
+ if (c >= 0x20 && c <= 0x7e) {
+ debug ("%c", c);
} else {
debug (".");
}
@@ -352,28 +385,28 @@ static void flash_write_cmd (flash_info_t * info, flash_sect_t sect,
uint offset, uchar cmd)
{

- volatile cfiptr_t addr;
+ void *addr;
cfiword_t cword;

- addr.cp = flash_make_addr (info, sect, offset);
+ addr = flash_make_addr (info, sect, offset);
flash_make_cmd (info, cmd, &cword);
switch (info->portwidth) {
case FLASH_CFI_8BIT:
- debug ("fwc addr %p cmd %x %x 8bit x %d bit\n", addr.cp, cmd,
+ debug ("fwc addr %p cmd %x %x 8bit x %d bit\n", addr, cmd,
cword.c, info->chipwidth << CFI_FLASH_SHIFT_WIDTH);
- *addr.cp = cword.c;
+ flash_write8(cword.c, addr);
break;
case FLASH_CFI_16BIT:
- debug ("fwc addr %p cmd %x %4.4x 16bit x %d bit\n", addr.wp,
+ debug ("fwc addr %p cmd %x %4.4x 16bit x %d bit\n", addr,
cmd, cword.w,
info->chipwidth << CFI_FLASH_SHIFT_WIDTH);
- *addr.wp = cword.w;
+ flash_write16(cword.w, addr);
break;
case FLASH_CFI_32BIT:
- debug ("fwc addr %p cmd %x %8.8lx 32bit x %d bit\n", addr.lp,
+ debug ("fwc addr %p cmd %x %8.8lx 32bit x %d bit\n", addr,
cmd, cword.l,
info->chipwidth << CFI_FLASH_SHIFT_WIDTH);
- *addr.lp = cword.l;
+ flash_write32(cword.l, addr);
break;
case FLASH_CFI_64BIT:
#ifdef DEBUG
@@ -383,11 +416,11 @@ static void flash_write_cmd (flash_info_t * info, flash_sect_t sect,
print_longlong (str, cword.ll);

debug ("fwrite addr %p cmd %x %s 64 bit x %d bit\n",
- addr.llp, cmd, str,
+ addr, cmd, str,
info->chipwidth << CFI_FLASH_SHIFT_WIDTH);
}
#endif
- *addr.llp = cword.ll;
+ flash_write64(cword.ll, addr);
break;
}

@@ -406,26 +439,26 @@ static void flash_unlock_seq (flash_info_t * info, flash_sect_t sect)
static int flash_isequal (flash_info_t * info, flash_sect_t sect,
uint offset, uchar cmd)
{
- cfiptr_t cptr;
+ void *addr;
cfiword_t cword;
int retval;

- cptr.cp = flash_make_addr (info, sect, offset);
+ addr = flash_make_addr (info, sect, offset);
flash_make_cmd (info, cmd, &cword);

- debug ("is= cmd %x(%c) addr %p ", cmd, cmd, cptr.cp);
+ debug ("is= cmd %x(%c) addr %p ", cmd, cmd, addr);
switch (info->portwidth) {
case FLASH_CFI_8BIT:
- debug ("is= %x %x\n", cptr.cp[0], cword.c);
- retval = (cptr.cp[0] == cword.c);
+ debug ("is= %x %x\n", flash_read8(addr), cword.c);
+ retval = (flash_read8(addr) == cword.c);
break;
case FLASH_CFI_16BIT:
- debug ("is= %4.4x %4.4x\n", cptr.wp[0], cword.w);
- retval = (cptr.wp[0] == cword.w);
+ debug ("is= %4.4x %4.4x\n", flash_read16(addr), cword.w);
+ retval = (flash_read16(addr) == cword.w);
break;
case FLASH_CFI_32BIT:
- debug ("is= %8.8lx %8.8lx\n", cptr.lp[0], cword.l);
- retval = (cptr.lp[0] == cword.l);
+ debug ("is= %8.8lx %8.8lx\n", flash_read32(addr), cword.l);
+ retval = (flash_read32(addr) == cword.l);
break;
case FLASH_CFI_64BIT:
#ifdef DEBUG
@@ -433,12 +466,12 @@ static int flash_isequal (flash_info_t * info, flash_sect_t sect,
char str1[20];
char str2[20];

- print_longlong (str1, cptr.llp[0]);
+ print_longlong (str1, flash_read64(addr));
print_longlong (str2, cword.ll);
debug ("is= %s %s\n", str1, str2);
}
#endif
- retval = (cptr.llp[0] == cword.ll);
+ retval = (flash_read64(addr) == cword.ll);
break;
default:
retval = 0;
@@ -452,24 +485,24 @@ static int flash_isequal (flash_info_t * info, flash_sect_t sect,
static int flash_isset (flash_info_t * info, flash_sect_t sect,
uint offset, uchar cmd)
{
- cfiptr_t cptr;
+ void *addr;
cfiword_t cword;
int retval;

- cptr.cp = flash_make_addr (info, sect, offset);
+ addr = flash_make_addr (info, sect, offset);
flash_make_cmd (info, cmd, &cword);
switch (info->portwidth) {
case FLASH_CFI_8BIT:
- retval = ((cptr.cp[0] & cword.c) == cword.c);
+ retval = ((flash_read8(addr) & cword.c) == cword.c);
break;
case FLASH_CFI_16BIT:
- retval = ((cptr.wp[0] & cword.w) == cword.w);
+ retval = ((flash_read16(addr) & cword.w) == cword.w);
break;
case FLASH_CFI_32BIT:
- retval = ((cptr.lp[0] & cword.l) == cword.l);
+ retval = ((flash_read16(addr) & cword.l) == cword.l);
break;
case FLASH_CFI_64BIT:
- retval = ((cptr.llp[0] & cword.ll) == cword.ll);
+ retval = ((flash_read64(addr) & cword.ll) == cword.ll);
break;
default:
retval = 0;
@@ -483,25 +516,28 @@ static int flash_isset (flash_info_t * info, flash_sect_t sect,
static int flash_toggle (flash_info_t * info, flash_sect_t sect,
uint offset, uchar cmd)
{
- cfiptr_t cptr;
+ void *addr;
cfiword_t cword;
int retval;

- cptr.cp = flash_make_addr (info, sect, offset);
+ addr = flash_make_addr (info, sect, offset);
flash_make_cmd (info, cmd, &cword);
switch (info->portwidth) {
case FLASH_CFI_8BIT:
- retval = ((cptr.cp[0] & cword.c) != (cptr.cp[0] & cword.c));
+ retval = ((flash_read8(addr) & cword.c) !=
+ (flash_read8(addr) & cword.c));
break;
case FLASH_CFI_16BIT:
- retval = ((cptr.wp[0] & cword.w) != (cptr.wp[0] & cword.w));
+ retval = ((flash_read16(addr) & cword.w) !=
+ (flash_read16(addr) & cword.w));
break;
case FLASH_CFI_32BIT:
- retval = ((cptr.lp[0] & cword.l) != (cptr.lp[0] & cword.l));
+ retval = ((flash_read32(addr) & cword.l) !=
+ (flash_read32(addr) & cword.l));
break;
case FLASH_CFI_64BIT:
- retval = ((cptr.llp[0] & cword.ll) !=
- (cptr.llp[0] & cword.ll));
+ retval = ((flash_read64(addr) & cword.ll) !=
+ (flash_read64(addr) & cword.ll));
break;
default:
retval = 0;
@@ -676,26 +712,26 @@ static flash_sect_t find_sector (flash_info_t * info, ulong addr)
static int flash_write_cfiword (flash_info_t * info, ulong dest,
cfiword_t cword)
{
- cfiptr_t ctladdr;
- cfiptr_t cptr;
+ void *ctladdr;
+ void *dstaddr;
int flag;

- ctladdr.cp = flash_make_addr (info, 0, 0);
- cptr.cp = (uchar *) dest;
+ ctladdr = flash_make_addr (info, 0, 0);
+ dstaddr = (uchar *)dest;

/* Check if Flash is (sufficiently) erased */
switch (info->portwidth) {
case FLASH_CFI_8BIT:
- flag = ((cptr.cp[0] & cword.c) == cword.c);
+ flag = ((flash_read8(dstaddr) & cword.c) == cword.c);
break;
case FLASH_CFI_16BIT:
- flag = ((cptr.wp[0] & cword.w) == cword.w);
+ flag = ((flash_read16(dstaddr) & cword.w) == cword.w);
break;
case FLASH_CFI_32BIT:
- flag = ((cptr.lp[0] & cword.l) == cword.l);
+ flag = ((flash_read32(dstaddr) & cword.l) == cword.l);
break;
case FLASH_CFI_64BIT:
- flag = ((cptr.llp[0] & cword.ll) == cword.ll);
+ flag = ((flash_read64(dstaddr) & cword.ll) == cword.ll);
break;
default:
return 2;
@@ -724,16 +760,16 @@ static int flash_write_cfiword (flash_info_t * info, ulong dest,

switch (info->portwidth) {
case FLASH_CFI_8BIT:
- cptr.cp[0] = cword.c;
+ flash_write8(cword.c, dstaddr);
break;
case FLASH_CFI_16BIT:
- cptr.wp[0] = cword.w;
+ flash_write16(cword.w, dstaddr);
break;
case FLASH_CFI_32BIT:
- cptr.lp[0] = cword.l;
+ flash_write32(cword.l, dstaddr);
break;
case FLASH_CFI_64BIT:
- cptr.llp[0] = cword.ll;
+ flash_write64(cword.ll, dstaddr);
break;
}

@@ -753,15 +789,14 @@ static int flash_write_cfibuffer (flash_info_t * info, ulong dest, uchar * cp,
flash_sect_t sector;
int cnt;
int retcode;
- volatile cfiptr_t src;
- volatile cfiptr_t dst;
+ void *src = cp;
+ void *dst = (void *)dest;
+
+ sector = find_sector (info, dest);

switch (info->vendor) {
case CFI_CMDSET_INTEL_STANDARD:
case CFI_CMDSET_INTEL_EXTENDED:
- src.cp = cp;
- dst.cp = (uchar *) dest;
- sector = find_sector (info, dest);
flash_write_cmd (info, sector, 0, FLASH_CMD_CLEAR_STATUS);
flash_write_cmd (info, sector, 0, FLASH_CMD_WRITE_TO_BUFFER);
retcode = flash_status_check (info, sector,
@@ -791,16 +826,20 @@ static int flash_write_cfibuffer (flash_info_t * info, ulong dest, uchar * cp,
while (cnt-- > 0) {
switch (info->portwidth) {
case FLASH_CFI_8BIT:
- *dst.cp++ = *src.cp++;
+ flash_write8(flash_read8(src), dst);
+ src += 1, dst += 1;
break;
case FLASH_CFI_16BIT:
- *dst.wp++ = *src.wp++;
+ flash_write16(flash_read16(src), dst);
+ src += 2, dst += 2;
break;
case FLASH_CFI_32BIT:
- *dst.lp++ = *src.lp++;
+ flash_write32(flash_read32(src), dst);
+ src += 4, dst += 4;
break;
case FLASH_CFI_64BIT:
- *dst.llp++ = *src.llp++;
+ flash_write64(flash_read64(src), dst);
+ src += 8, dst += 8;
break;
default:
return ERR_INVAL;
@@ -817,10 +856,6 @@ static int flash_write_cfibuffer (flash_info_t * info, ulong dest, uchar * cp,

case CFI_CMDSET_AMD_STANDARD:
case CFI_CMDSET_AMD_EXTENDED:
- src.cp = cp;
- dst.cp = (uchar *) dest;
- sector = find_sector (info, dest);
-
flash_unlock_seq(info,0);
flash_write_cmd (info, sector, 0, AMD_CMD_WRITE_TO_BUFFER);

@@ -828,22 +863,34 @@ static int flash_write_cfibuffer (flash_info_t * info, ulong dest, uchar * cp,
case FLASH_CFI_8BIT:
cnt = len;
flash_write_cmd (info, sector, 0, (uchar) cnt - 1);
- while (cnt-- > 0) *dst.cp++ = *src.cp++;
+ while (cnt-- > 0) {
+ flash_write8(flash_read8(src), dst);
+ src += 1, dst += 1;
+ }
break;
case FLASH_CFI_16BIT:
cnt = len >> 1;
flash_write_cmd (info, sector, 0, (uchar) cnt - 1);
- while (cnt-- > 0) *dst.wp++ = *src.wp++;
+ while (cnt-- > 0) {
+ flash_write16(flash_read16(src), dst);
+ src += 2, dst += 2;
+ }
break;
case FLASH_CFI_32BIT:
cnt = len >> 2;
flash_write_cmd (info, sector, 0, (uchar) cnt - 1);
- while (cnt-- > 0) *dst.lp++ = *src.lp++;
+ while (cnt-- > 0) {
+ flash_write32(flash_read32(src), dst);
+ src += 4, dst += 4;
+ }
break;
case FLASH_CFI_64BIT:
cnt = len >> 3;
flash_write_cmd (info, sector, 0, (uchar) cnt - 1);
- while (cnt-- > 0) *dst.llp++ = *src.llp++;
+ while (cnt-- > 0) {
+ flash_write64(flash_read64(src), dst);
+ src += 8, dst += 8;
+ }
break;
default:
return ERR_INVAL;
--
1.5.3.4