[U-Boot] [PATCH] cfi_flash: Micron Nor flash don't support read operation after send write command

[Qi Wang 王起 (qiwang)]

Micron Nor flash don't support read operation after send write command. As below,

	flash_write_cmd(info, sector, offset, AMD_CMD_WRITE_TO_BUFFER);
	cnt = len >> shift;
	flash_write_cmd(info, sector, offset, cnt - 1);

	switch (info->portwidth) {
	case FLASH_CFI_8BIT:
		while (cnt-- > 0) {
			flash_write8(flash_read8(src), dst);
			src += 1, dst += 1;
		}
	break;

If the src address locate in NOR flash, flash_read operation will be failed.
So, read out the data to DRAM before send write command operation.

Signed-off-by: Qi Wang<qiwang at micron.com>
---
drivers/mtd/cfi_flash.c |   70 +++++++++++++++++++++++++++++++----------------
 1 file changed, 46 insertions(+), 24 deletions(-)

diff --git a/drivers/mtd/cfi_flash.c b/drivers/mtd/cfi_flash.c index a389cd1..0f532c0 100644
--- a/drivers/mtd/cfi_flash.c
+++ b/drivers/mtd/cfi_flash.c
@@ -25,6 +25,8 @@
 #include <environment.h>
 #include <mtd/cfi_flash.h>
 #include <watchdog.h>
+#include <malloc.h>
+#include <asm-generic/errno.h>
 
 /*
  * This file implements a Common Flash Interface (CFI) driver for @@ -855,6 +857,8 @@ static int flash_write_cfibuffer (flash_info_t * info, ulong dest, uchar * cp,
 	int cnt;
 	int retcode;
 	void *src = cp;
+	void *src2;
+	void *src2_bak;
 	void *dst = (void *)dest;
 	void *dst2 = dst;
 	int flag = 1;
@@ -880,29 +884,45 @@ static int flash_write_cfibuffer (flash_info_t * info, ulong dest, uchar * cp,
 		goto out_unmap;
 	}
 
+	src2 = malloc(len);
+	if(!src2)
+	{
+		free(src2);
+		return -ENOMEM;
+	}
+
+	src2_bak = src2;
 	cnt = len >> shift;
 
 	while ((cnt-- > 0) && (flag == 1)) {
 		switch (info->portwidth) {
 		case FLASH_CFI_8BIT:
-			flag = ((flash_read8(dst2) & flash_read8(src)) ==
-				flash_read8(src));
+			*(u8 *)src2 = flash_read8(src);
+			flag = ((flash_read8(dst2) & *(u8 *)src2) ==
+				*(u8 *)src2);
 			src += 1, dst2 += 1;
+			src2 +=1;
 			break;
 		case FLASH_CFI_16BIT:
-			flag = ((flash_read16(dst2) & flash_read16(src)) ==
-				flash_read16(src));
+			*(u16 *)src2 = flash_read16(src);
+			flag = ((flash_read16(dst2) & *(u16 *)src2) ==
+				*(u16 *)src2);
 			src += 2, dst2 += 2;
+			src2 += 2;
 			break;
 		case FLASH_CFI_32BIT:
-			flag = ((flash_read32(dst2) & flash_read32(src)) ==
-				flash_read32(src));
+			*(u32 *)src2 = flash_read32(src);
+			flag = ((flash_read32(dst2) & *(u32 *)src2) ==
+				*(u32 *)src2);
 			src += 4, dst2 += 4;
+			src2 += 4;
 			break;
 		case FLASH_CFI_64BIT:
-			flag = ((flash_read64(dst2) & flash_read64(src)) ==
-				flash_read64(src));
+			*(u64 *)src2 = flash_read64(src);
+			flag = ((flash_read64(dst2) & *(u64 *)src2) ==
+				*(u64 *)src2);
 			src += 8, dst2 += 8;
+			src2 += 8;
 			break;
 		}
 	}
@@ -912,6 +932,7 @@ static int flash_write_cfibuffer (flash_info_t * info, ulong dest, uchar * cp,
 	}
 
 	src = cp;
+	src2 = src2_bak;
 	sector = find_sector (info, dest);
 
 	switch (info->vendor) {
@@ -934,20 +955,20 @@ static int flash_write_cfibuffer (flash_info_t * info, ulong dest, uchar * cp,
 			while (cnt-- > 0) {
 				switch (info->portwidth) {
 				case FLASH_CFI_8BIT:
-					flash_write8(flash_read8(src), dst);
-					src += 1, dst += 1;
+					flash_write8(*(u8 *)src2, dst);
+					src2 += 1, dst += 1;
 					break;
 				case FLASH_CFI_16BIT:
-					flash_write16(flash_read16(src), dst);
-					src += 2, dst += 2;
+					flash_write16(*(u16 *)src2, dst);
+					src2 += 2, dst += 2;
 					break;
 				case FLASH_CFI_32BIT:
-					flash_write32(flash_read32(src), dst);
-					src += 4, dst += 4;
+					flash_write32(*(u32 *)src2, dst);
+					src2 += 4, dst += 4;
 					break;
 				case FLASH_CFI_64BIT:
-					flash_write64(flash_read64(src), dst);
-					src += 8, dst += 8;
+					flash_write64(*(u64 *)src2, dst);
+					src2 += 8, dst += 8;
 					break;
 				default:
 					retcode = ERR_INVAL;
@@ -977,26 +998,26 @@ static int flash_write_cfibuffer (flash_info_t * info, ulong dest, uchar * cp,
 		switch (info->portwidth) {
 		case FLASH_CFI_8BIT:
 			while (cnt-- > 0) {
-				flash_write8(flash_read8(src), dst);
-				src += 1, dst += 1;
+				flash_write8(*(u8 *)src2, dst);
+				src2 += 1, dst += 1;
 			}
 			break;
 		case FLASH_CFI_16BIT:
 			while (cnt-- > 0) {
-				flash_write16(flash_read16(src), dst);
-				src += 2, dst += 2;
+				flash_write16(*(u16 *)src2, dst);
+				src2 += 2, dst += 2;
 			}
 			break;
 		case FLASH_CFI_32BIT:
 			while (cnt-- > 0) {
-				flash_write32(flash_read32(src), dst);
-				src += 4, dst += 4;
+				flash_write32(*(u32 *)src2, dst);
+				src2 += 4, dst += 4;
 			}
 			break;
 		case FLASH_CFI_64BIT:
 			while (cnt-- > 0) {
-				flash_write64(flash_read64(src), dst);
-				src += 8, dst += 8;
+				flash_write64(*(u64 *)src2, dst);
+				src2 += 8, dst += 8;
 			}
 			break;
 		default:
@@ -1023,6 +1044,7 @@ static int flash_write_cfibuffer (flash_info_t * info, ulong dest, uchar * cp,
 	}
 
 out_unmap:
+	free(src2_bak);
 	return retcode;
 }
 #endif /* CONFIG_SYS_FLASH_USE_BUFFER_WRITE */
--
1.7.9.5

Qi Wang
Best wishes