[PATCH v2] mtd: spi-nor: Fix the spi_nor_read() when config SPI_STACKED_PARALLEL is enabled

Update the spi_nor_read() function only for parallel configuration when config SPI_STACKED_PARALLEL is enabled and keep the default code as is. For parallel configurations fix the read issue for 4byte address width by passing the entire length to the read function, split the memory of 16MB size banks only when the address width is 3byte. Also update the size when the configuration is stacked.
Fixes: 5d40b3d384 ("mtd: spi-nor: Add parallel and stacked memories support") Signed-off-by: Venkatesh Yadav Abbarapu venkatesh.abbarapu@amd.com --- Changes in v2: - Update the nor read for parallel configuration and for other case keep the code as is. - Fixed the commit description. - Tested the changes with s25fl128s flash Zynq> sf probe 0 0 0 SF: Detected s25fl128s with page size 256 Bytes, erase size 64 KiB, total 16 MiB Zynq> time sf erase 0x0 0x1000000;mw.b 0x8000 aabbccdd 0x1000000;time sf write 0x8000 0x0 0x1000000;mw.b 0x8008000 0x0 0x1000000;time sf read 0x8008000 0x0 0x1000000;cmp.b 0x8000 0x8008000 0x1000000 SF: 16777216 bytes @ 0x0 Erased: OK
time: 32.464 seconds device 0 whole chip SF: 16777216 bytes @ 0x0 Written: OK
time: 15.515 seconds device 0 whole chip SF: 16777216 bytes @ 0x0 Read: OK
time: 1.557 seconds Total of 16777216 byte(s) were the same --- drivers/mtd/spi/spi-nor-core.c | 50 ++++++++++++++++++++++------------ 1 file changed, 33 insertions(+), 17 deletions(-)
diff --git a/drivers/mtd/spi/spi-nor-core.c b/drivers/mtd/spi/spi-nor-core.c index ec841fb13b..8d7087b5c9 100644 --- a/drivers/mtd/spi/spi-nor-core.c +++ b/drivers/mtd/spi/spi-nor-core.c @@ -1140,7 +1140,7 @@ static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr) nor->spi->flags &= ~SPI_XFER_U_PAGE; } #ifdef CONFIG_SPI_FLASH_BAR - ret = write_bar(nor, addr); + ret = write_bar(nor, offset); if (ret < 0) goto erase_err; #endif @@ -1152,7 +1152,7 @@ static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr) !(nor->flags & SNOR_F_NO_OP_CHIP_ERASE)) { ret = spi_nor_erase_chip(nor); } else { - ret = spi_nor_erase_sector(nor, addr); + ret = spi_nor_erase_sector(nor, offset); } if (ret < 0) goto erase_err; @@ -1578,8 +1578,8 @@ static int spi_nor_read(struct mtd_info *mtd, loff_t from, size_t len, struct spi_nor *nor = mtd_to_spi_nor(mtd); int ret; loff_t offset = from; - u32 read_len = 0; u32 rem_bank_len = 0; + u32 stack_shift = 0; u8 bank; bool is_ofst_odd = false;
@@ -1593,18 +1593,23 @@ static int spi_nor_read(struct mtd_info *mtd, loff_t from, size_t len, }
while (len) { - bank = (u32)from / SZ_16M; - if (nor->flags & SNOR_F_HAS_PARALLEL) - bank /= 2; - - rem_bank_len = SZ_16M * (bank + 1); - if (nor->flags & SNOR_F_HAS_PARALLEL) - rem_bank_len *= 2; - rem_bank_len -= from; - + size_t read_len = len; offset = from;
+ if (CONFIG_IS_ENABLED(SPI_STACKED_PARALLEL)) { + if (nor->addr_width == 3) { + bank = (u32)from / SZ_16M; + if (nor->flags & SNOR_F_HAS_PARALLEL) + bank /= 2; + + rem_bank_len = SZ_16M * (bank + 1); + if (nor->flags & SNOR_F_HAS_PARALLEL) + rem_bank_len *= 2; + rem_bank_len -= from; + } + if (nor->flags & SNOR_F_HAS_STACKED) { + stack_shift = 1; if (offset >= (mtd->size / 2)) { offset = offset - (mtd->size / 2); nor->spi->flags |= SPI_XFER_U_PAGE; @@ -1613,20 +1618,31 @@ static int spi_nor_read(struct mtd_info *mtd, loff_t from, size_t len, } }
+ if (nor->addr_width == 4) + rem_bank_len = (mtd->size >> stack_shift) - offset; + if (nor->flags & SNOR_F_HAS_PARALLEL) offset /= 2; + }
#ifdef CONFIG_SPI_FLASH_BAR + u32 remain_len; + ret = write_bar(nor, offset); if (ret < 0) return log_ret(ret); -#endif - - if (len < rem_bank_len) + remain_len = (SZ_16M * (nor->bank_curr + 1)) - offset; + if (len < remain_len) read_len = len; else - read_len = rem_bank_len; - + read_len = remain_len; +#endif + if (CONFIG_IS_ENABLED(SPI_STACKED_PARALLEL)) { + if (len < rem_bank_len) + read_len = len; + else + read_len = rem_bank_len; + } if (read_len == 0) return -EIO;

Venkatesh Yadav Abbarapu venkatesh.abbarapu@amd.com writes:
Update the spi_nor_read() function only for parallel configuration when config SPI_STACKED_PARALLEL is enabled and keep the default code as is. For parallel configurations fix the read issue for 4byte address width by passing the entire length to the read function, split the memory of 16MB size banks only when the address width is 3byte. Also update the size when the configuration is stacked.
Fixes: 5d40b3d384 ("mtd: spi-nor: Add parallel and stacked memories support") Signed-off-by: Venkatesh Yadav Abbarapu venkatesh.abbarapu@amd.com
Changes in v2:
- Update the nor read for parallel configuration and for other case keep the code as is.
- Fixed the commit description.
- Tested the changes with s25fl128s flash
Zynq> sf probe 0 0 0 SF: Detected s25fl128s with page size 256 Bytes, erase size 64 KiB, total 16 MiB Zynq> time sf erase 0x0 0x1000000;mw.b 0x8000 aabbccdd 0x1000000;time sf write 0x8000 0x0 0x1000000;mw.b 0x8008000 0x0 0x1000000;time sf read 0x8008000 0x0 0x1000000;cmp.b 0x8000 0x8008000 0x1000000 SF: 16777216 bytes @ 0x0 Erased: OK
time: 32.464 seconds device 0 whole chip SF: 16777216 bytes @ 0x0 Written: OK
time: 15.515 seconds device 0 whole chip SF: 16777216 bytes @ 0x0 Read: OK
time: 1.557 seconds Total of 16777216 byte(s) were the same
drivers/mtd/spi/spi-nor-core.c | 50 ++++++++++++++++++++++------------ 1 file changed, 33 insertions(+), 17 deletions(-)
diff --git a/drivers/mtd/spi/spi-nor-core.c b/drivers/mtd/spi/spi-nor-core.c index ec841fb13b..8d7087b5c9 100644 --- a/drivers/mtd/spi/spi-nor-core.c +++ b/drivers/mtd/spi/spi-nor-core.c @@ -1140,7 +1140,7 @@ static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr) nor->spi->flags &= ~SPI_XFER_U_PAGE; } #ifdef CONFIG_SPI_FLASH_BAR
ret = write_bar(nor, addr);
if (ret < 0) goto erase_err;ret = write_bar(nor, offset);
#endif @@ -1152,7 +1152,7 @@ static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr) !(nor->flags & SNOR_F_NO_OP_CHIP_ERASE)) { ret = spi_nor_erase_chip(nor); } else {
ret = spi_nor_erase_sector(nor, addr);
} if (ret < 0) goto erase_err;ret = spi_nor_erase_sector(nor, offset);
@@ -1578,8 +1578,8 @@ static int spi_nor_read(struct mtd_info *mtd, loff_t from, size_t len, struct spi_nor *nor = mtd_to_spi_nor(mtd); int ret; loff_t offset = from;
- u32 read_len = 0; u32 rem_bank_len = 0;
- u32 stack_shift = 0; u8 bank; bool is_ofst_odd = false;
@@ -1593,18 +1593,23 @@ static int spi_nor_read(struct mtd_info *mtd, loff_t from, size_t len, }
while (len) {
bank = (u32)from / SZ_16M;
if (nor->flags & SNOR_F_HAS_PARALLEL)
bank /= 2;
rem_bank_len = SZ_16M * (bank + 1);
if (nor->flags & SNOR_F_HAS_PARALLEL)
rem_bank_len *= 2;
rem_bank_len -= from;
size_t read_len = len;
offset = from;
if (CONFIG_IS_ENABLED(SPI_STACKED_PARALLEL)) {
if (nor->addr_width == 3) {
bank = (u32)from / SZ_16M;
if (nor->flags & SNOR_F_HAS_PARALLEL)
bank /= 2;
rem_bank_len = SZ_16M * (bank + 1);
if (nor->flags & SNOR_F_HAS_PARALLEL)
rem_bank_len *= 2;
rem_bank_len -= from;
}
if (nor->flags & SNOR_F_HAS_STACKED) {
stack_shift = 1; if (offset >= (mtd->size / 2)) { offset = offset - (mtd->size / 2); nor->spi->flags |= SPI_XFER_U_PAGE;
@@ -1613,20 +1618,31 @@ static int spi_nor_read(struct mtd_info *mtd, loff_t from, size_t len, } }
if (nor->addr_width == 4)
rem_bank_len = (mtd->size >> stack_shift) - offset;
- if (nor->flags & SNOR_F_HAS_PARALLEL) offset /= 2;
- }
#ifdef CONFIG_SPI_FLASH_BAR
u32 remain_len;
- ret = write_bar(nor, offset); if (ret < 0) return log_ret(ret);
-#endif
if (len < rem_bank_len)
remain_len = (SZ_16M * (nor->bank_curr + 1)) - offset;
elseif (len < remain_len) read_len = len;
read_len = rem_bank_len;
read_len = remain_len;
+#endif
if (CONFIG_IS_ENABLED(SPI_STACKED_PARALLEL)) {
if (len < rem_bank_len)
read_len = len;
else
read_len = rem_bank_len;
if (read_len == 0) return -EIO;}
-- 2.34.1
Tested-by: Jonathan Humphreys j-humphreys@ti.com

On 12/11/24 1:06 PM, Venkatesh Yadav Abbarapu wrote:
Update the spi_nor_read() function only for parallel configuration when config SPI_STACKED_PARALLEL is enabled and keep the default code as is. For parallel configurations fix the read issue for 4byte address width by passing the entire length to the read function, split the memory of 16MB size banks only when the address width is 3byte. Also update the size when the configuration is stacked.
Fixes: 5d40b3d384 ("mtd: spi-nor: Add parallel and stacked memories support") Signed-off-by: Venkatesh Yadav Abbarapu venkatesh.abbarapu@amd.com
Changes in v2:
- Update the nor read for parallel configuration and for other case keep the code as is.
- Fixed the commit description.
- Tested the changes with s25fl128s flash
Zynq> sf probe 0 0 0 SF: Detected s25fl128s with page size 256 Bytes, erase size 64 KiB, total 16 MiB Zynq> time sf erase 0x0 0x1000000;mw.b 0x8000 aabbccdd 0x1000000;time sf write 0x8000 0x0 0x1000000;mw.b 0x8008000 0x0 0x1000000;time sf read 0x8008000 0x0 0x1000000;cmp.b 0x8000 0x8008000 0x1000000 SF: 16777216 bytes @ 0x0 Erased: OK
time: 32.464 seconds device 0 whole chip SF: 16777216 bytes @ 0x0 Written: OK
time: 15.515 seconds device 0 whole chip SF: 16777216 bytes @ 0x0 Read: OK
time: 1.557 seconds Total of 16777216 byte(s) were the same
drivers/mtd/spi/spi-nor-core.c | 50 ++++++++++++++++++++++------------ 1 file changed, 33 insertions(+), 17 deletions(-)
diff --git a/drivers/mtd/spi/spi-nor-core.c b/drivers/mtd/spi/spi-nor-core.c index ec841fb13b..8d7087b5c9 100644 --- a/drivers/mtd/spi/spi-nor-core.c +++ b/drivers/mtd/spi/spi-nor-core.c @@ -1140,7 +1140,7 @@ static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr) nor->spi->flags &= ~SPI_XFER_U_PAGE; } #ifdef CONFIG_SPI_FLASH_BAR
ret = write_bar(nor, addr);
ret = write_bar(nor, offset);
This change is really inobvious, the code above likely needs to be compiled out if the SPI_STACKED_PARALLEL stuff is disabled ?
" diff --git a/drivers/mtd/spi/spi-nor-core.c b/drivers/mtd/spi/spi-nor-core.c index 8d7087b5c95..691962ef271 100644 --- a/drivers/mtd/spi/spi-nor-core.c +++ b/drivers/mtd/spi/spi-nor-core.c @@ -1130,6 +1130,7 @@ static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr) goto erase_err; } offset = addr; + if (CONFIG_IS_ENABLED(SPI_STACKED_PARALLEL)) { if (nor->flags & SNOR_F_HAS_PARALLEL) offset /= 2;
@@ -1139,6 +1140,7 @@ static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr) else nor->spi->flags &= ~SPI_XFER_U_PAGE; } + } #ifdef CONFIG_SPI_FLASH_BAR ret = write_bar(nor, offset); if (ret < 0) "
if (ret < 0) goto erase_err;
#endif @@ -1152,7 +1152,7 @@ static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr) !(nor->flags & SNOR_F_NO_OP_CHIP_ERASE)) { ret = spi_nor_erase_chip(nor); } else {
ret = spi_nor_erase_sector(nor, addr);
} if (ret < 0) goto erase_err;ret = spi_nor_erase_sector(nor, offset);
@@ -1578,8 +1578,8 @@ static int spi_nor_read(struct mtd_info *mtd, loff_t from, size_t len, struct spi_nor *nor = mtd_to_spi_nor(mtd); int ret; loff_t offset = from;
- u32 read_len = 0; u32 rem_bank_len = 0;
- u32 stack_shift = 0; u8 bank; bool is_ofst_odd = false;
@@ -1593,18 +1593,23 @@ static int spi_nor_read(struct mtd_info *mtd, loff_t from, size_t len, }
while (len) {
bank = (u32)from / SZ_16M;
if (nor->flags & SNOR_F_HAS_PARALLEL)
bank /= 2;
rem_bank_len = SZ_16M * (bank + 1);
if (nor->flags & SNOR_F_HAS_PARALLEL)
rem_bank_len *= 2;
rem_bank_len -= from;
size_t read_len = len;
offset = from;
if (CONFIG_IS_ENABLED(SPI_STACKED_PARALLEL)) {
if (nor->addr_width == 3) {
bank = (u32)from / SZ_16M;
if (nor->flags & SNOR_F_HAS_PARALLEL)
bank /= 2;
rem_bank_len = SZ_16M * (bank + 1);
if (nor->flags & SNOR_F_HAS_PARALLEL)
rem_bank_len *= 2;
rem_bank_len -= from;
}
if (nor->flags & SNOR_F_HAS_STACKED) {
stack_shift = 1; if (offset >= (mtd->size / 2)) { offset = offset - (mtd->size / 2); nor->spi->flags |= SPI_XFER_U_PAGE;
@@ -1613,20 +1618,31 @@ static int spi_nor_read(struct mtd_info *mtd, loff_t from, size_t len, } }
if (nor->addr_width == 4)
rem_bank_len = (mtd->size >> stack_shift) - offset;
if (nor->flags & SNOR_F_HAS_PARALLEL) offset /= 2;
}
#ifdef CONFIG_SPI_FLASH_BAR
u32 remain_len;
ret = write_bar(nor, offset); if (ret < 0) return log_ret(ret);
-#endif
if (len < rem_bank_len)
remain_len = (SZ_16M * (nor->bank_curr + 1)) - offset;
elseif (len < remain_len) read_len = len;
read_len = rem_bank_len;
read_len = remain_len;
+#endif
if (CONFIG_IS_ENABLED(SPI_STACKED_PARALLEL)) {
if (len < rem_bank_len)
read_len = len;
else
read_len = rem_bank_len;
}
If I look at this change with 'git show -w' , the change looks like this:
" #ifdef CONFIG_SPI_FLASH_BAR + u32 remain_len; + ret = write_bar(nor, offset); if (ret < 0) return log_ret(ret); + remain_len = (SZ_16M * (nor->bank_curr + 1)) - offset; + if (len < remain_len) + read_len = len; + else + read_len = remain_len; #endif - + if (CONFIG_IS_ENABLED(SPI_STACKED_PARALLEL)) { if (len < rem_bank_len) read_len = len; else read_len = rem_bank_len; - + } if (read_len == 0) return -EIO; "
Why is there this part of code twice now, ifdeffed out differently in each case ?
" if (len < rem_bank_len) read_len = len; else read_len = rem_bank_len; "

-----Original Message----- From: Marek Vasut marex@denx.de Sent: Monday, December 16, 2024 5:21 AM To: Abbarapu, Venkatesh venkatesh.abbarapu@amd.com; u-boot@lists.denx.de; tudor.ambarus@linaro.org; j-humphreys@ti.com Cc: Simek, Michal michal.simek@amd.com; jagan@amarulasolutions.com; vigneshr@ti.com; u-kumar1@ti.com; trini@konsulko.com; seanga2@gmail.com; caleb.connolly@linaro.org; sjg@chromium.org; william.zhang@broadcom.com; stefan_b@posteo.net; quentin.schulz@cherry.de; Takahiro.Kuwano@infineon.com; p-mantena@ti.com; git (AMD-Xilinx) git@amd.com Subject: Re: [PATCH v2] mtd: spi-nor: Fix the spi_nor_read() when config SPI_STACKED_PARALLEL is enabled
On 12/11/24 1:06 PM, Venkatesh Yadav Abbarapu wrote:
Update the spi_nor_read() function only for parallel configuration when config SPI_STACKED_PARALLEL is enabled and keep the default code as is. For parallel configurations fix the read issue for 4byte address width by passing the entire length to the read function, split the memory of 16MB size banks only when the address width is 3byte. Also update the size when the configuration is stacked.
Fixes: 5d40b3d384 ("mtd: spi-nor: Add parallel and stacked memories support") Signed-off-by: Venkatesh Yadav Abbarapu venkatesh.abbarapu@amd.com
Changes in v2:
- Update the nor read for parallel configuration and for other case keep the code as is.
- Fixed the commit description.
- Tested the changes with s25fl128s flash
Zynq> sf probe 0 0 0 SF: Detected s25fl128s with page size 256 Bytes, erase size 64 KiB, total 16 MiB Zynq> time sf erase 0x0 0x1000000;mw.b 0x8000 aabbccdd 0x1000000;time Zynq> sf write 0x8000 0x0 0x1000000;mw.b 0x8008000 0x0 0x1000000;time Zynq> sf read 0x8008000 0x0 0x1000000;cmp.b 0x8000 0x8008000 0x1000000 SF: 16777216 bytes @ 0x0 Erased: OK
time: 32.464 seconds device 0 whole chip SF: 16777216 bytes @ 0x0 Written: OK
time: 15.515 seconds device 0 whole chip SF: 16777216 bytes @ 0x0 Read: OK
time: 1.557 seconds Total of 16777216 byte(s) were the same
drivers/mtd/spi/spi-nor-core.c | 50 ++++++++++++++++++++++------------ 1 file changed, 33 insertions(+), 17 deletions(-)
diff --git a/drivers/mtd/spi/spi-nor-core.c b/drivers/mtd/spi/spi-nor-core.c index ec841fb13b..8d7087b5c9 100644 --- a/drivers/mtd/spi/spi-nor-core.c +++ b/drivers/mtd/spi/spi-nor-core.c @@ -1140,7 +1140,7 @@ static int spi_nor_erase(struct mtd_info *mtd, struct
erase_info *instr)
nor->spi->flags &= ~SPI_XFER_U_PAGE; }
#ifdef CONFIG_SPI_FLASH_BAR
ret = write_bar(nor, addr);
ret = write_bar(nor, offset);
This change is really inobvious, the code above likely needs to be compiled out if the SPI_STACKED_PARALLEL stuff is disabled ?
In the spi_nor_erase() offset = addr; if(PARALLEL) offset/=2; so for parallel or single configuration we need to pass "offset" to write_bar() write_bar(nor, offset");
" diff --git a/drivers/mtd/spi/spi-nor-core.c b/drivers/mtd/spi/spi-nor-core.c index 8d7087b5c95..691962ef271 100644 --- a/drivers/mtd/spi/spi-nor-core.c +++ b/drivers/mtd/spi/spi-nor-core.c @@ -1130,6 +1130,7 @@ static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr) goto erase_err; } offset = addr;
if (CONFIG_IS_ENABLED(SPI_STACKED_PARALLEL)) { if (nor->flags & SNOR_F_HAS_PARALLEL) offset /= 2;
@@ -1139,6 +1140,7 @@ static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr) else nor->spi->flags &= ~SPI_XFER_U_PAGE; }
#ifdef CONFIG_SPI_FLASH_BAR ret = write_bar(nor, offset); if (ret < 0)}
"
if (ret < 0) goto erase_err;
#endif @@ -1152,7 +1152,7 @@ static int spi_nor_erase(struct mtd_info *mtd, struct
erase_info *instr)
!(nor->flags & SNOR_F_NO_OP_CHIP_ERASE)) { ret = spi_nor_erase_chip(nor); } else {
ret = spi_nor_erase_sector(nor, addr);
} if (ret < 0) goto erase_err;ret = spi_nor_erase_sector(nor, offset);
@@ -1578,8 +1578,8 @@ static int spi_nor_read(struct mtd_info *mtd, loff_t from,
size_t len,
struct spi_nor *nor = mtd_to_spi_nor(mtd); int ret; loff_t offset = from;
- u32 read_len = 0; u32 rem_bank_len = 0;
- u32 stack_shift = 0; u8 bank; bool is_ofst_odd = false;
@@ -1593,18 +1593,23 @@ static int spi_nor_read(struct mtd_info *mtd, loff_t
from, size_t len,
}
while (len) {
bank = (u32)from / SZ_16M;
if (nor->flags & SNOR_F_HAS_PARALLEL)
bank /= 2;
rem_bank_len = SZ_16M * (bank + 1);
if (nor->flags & SNOR_F_HAS_PARALLEL)
rem_bank_len *= 2;
rem_bank_len -= from;
size_t read_len = len;
offset = from;
if (CONFIG_IS_ENABLED(SPI_STACKED_PARALLEL)) {
if (nor->addr_width == 3) {
bank = (u32)from / SZ_16M;
if (nor->flags & SNOR_F_HAS_PARALLEL)
bank /= 2;
rem_bank_len = SZ_16M * (bank + 1);
if (nor->flags & SNOR_F_HAS_PARALLEL)
rem_bank_len *= 2;
rem_bank_len -= from;
}
if (nor->flags & SNOR_F_HAS_STACKED) {
stack_shift = 1; if (offset >= (mtd->size / 2)) { offset = offset - (mtd->size / 2); nor->spi->flags |= SPI_XFER_U_PAGE; @@ -
1613,20 +1618,31 @@
static int spi_nor_read(struct mtd_info *mtd, loff_t from, size_t len, } }
if (nor->addr_width == 4)
rem_bank_len = (mtd->size >> stack_shift) - offset;
if (nor->flags & SNOR_F_HAS_PARALLEL) offset /= 2;
}
#ifdef CONFIG_SPI_FLASH_BAR
u32 remain_len;
ret = write_bar(nor, offset); if (ret < 0) return log_ret(ret);
-#endif
if (len < rem_bank_len)
remain_len = (SZ_16M * (nor->bank_curr + 1)) - offset;
elseif (len < remain_len) read_len = len;
read_len = rem_bank_len;
read_len = remain_len;
+#endif
if (CONFIG_IS_ENABLED(SPI_STACKED_PARALLEL)) {
if (len < rem_bank_len)
read_len = len;
else
read_len = rem_bank_len;
}
If I look at this change with 'git show -w' , the change looks like this:
" #ifdef CONFIG_SPI_FLASH_BAR
u32 remain_len;
ret = write_bar(nor, offset); if (ret < 0) return log_ret(ret);
remain_len = (SZ_16M * (nor->bank_curr + 1)) - offset;
if (len < remain_len)
read_len = len;
else
#endifread_len = remain_len;
if (CONFIG_IS_ENABLED(SPI_STACKED_PARALLEL)) { if (len < rem_bank_len) read_len = len; else read_len = rem_bank_len;
} if (read_len == 0) return -EIO;
"
Why is there this part of code twice now, ifdeffed out differently in each case ?
" if (len < rem_bank_len) read_len = len; else read_len = rem_bank_len; "
For parallel/stacked configuration and address width the "rem_bank_len" will vary and as we don't want to disturb the default read functionality added the ifdef separately.
Thanks Venkatesh

On 12/16/24 5:16 AM, Abbarapu, Venkatesh wrote:
[...]
+++ b/drivers/mtd/spi/spi-nor-core.c @@ -1140,7 +1140,7 @@ static int spi_nor_erase(struct mtd_info *mtd, struct
erase_info *instr)
nor->spi->flags &= ~SPI_XFER_U_PAGE; }
#ifdef CONFIG_SPI_FLASH_BAR
ret = write_bar(nor, addr);
ret = write_bar(nor, offset);
This change is really inobvious, the code above likely needs to be compiled out if the SPI_STACKED_PARALLEL stuff is disabled ?
In the spi_nor_erase() offset = addr; if(PARALLEL) offset/=2; so for parallel or single configuration we need to pass "offset" to write_bar() write_bar(nor, offset");
The code above likely needs to be compiled out if the SPI_STACKED_PARALLEL stuff is disabled ?
[...]
If I look at this change with 'git show -w' , the change looks like this:
" #ifdef CONFIG_SPI_FLASH_BAR
u32 remain_len;
ret = write_bar(nor, offset); if (ret < 0) return log_ret(ret);
remain_len = (SZ_16M * (nor->bank_curr + 1)) - offset;
if (len < remain_len)
read_len = len;
else
#endifread_len = remain_len;
if (CONFIG_IS_ENABLED(SPI_STACKED_PARALLEL)) { if (len < rem_bank_len) read_len = len; else read_len = rem_bank_len;
} if (read_len == 0) return -EIO;
"
Why is there this part of code twice now, ifdeffed out differently in each case ?
" if (len < rem_bank_len) read_len = len; else read_len = rem_bank_len; "
For parallel/stacked configuration and address width the "rem_bank_len" will vary and as we don't want to disturb the default read functionality added the ifdef separately.
What would happen if both SPI_FLASH_BAR and SPI_STACKED_PARALLEL are enabled on a system that only has one SPI NOR attached (non-stacked/parallel) ? I noticed the second "copy" of the code behaves slightly differently in the else branch, so does that mean this would break such setup ?

-----Original Message----- From: Marek Vasut marex@denx.de Sent: Monday, December 16, 2024 4:06 PM To: Abbarapu, Venkatesh venkatesh.abbarapu@amd.com; u-boot@lists.denx.de; tudor.ambarus@linaro.org; j-humphreys@ti.com Cc: Simek, Michal michal.simek@amd.com; jagan@amarulasolutions.com; vigneshr@ti.com; u-kumar1@ti.com; trini@konsulko.com; seanga2@gmail.com; caleb.connolly@linaro.org; sjg@chromium.org; william.zhang@broadcom.com; stefan_b@posteo.net; quentin.schulz@cherry.de; Takahiro.Kuwano@infineon.com; p-mantena@ti.com; git (AMD-Xilinx) git@amd.com Subject: Re: [PATCH v2] mtd: spi-nor: Fix the spi_nor_read() when config SPI_STACKED_PARALLEL is enabled
On 12/16/24 5:16 AM, Abbarapu, Venkatesh wrote:
[...]
+++ b/drivers/mtd/spi/spi-nor-core.c @@ -1140,7 +1140,7 @@ static int spi_nor_erase(struct mtd_info *mtd, struct
erase_info *instr)
nor->spi->flags &= ~SPI_XFER_U_PAGE; }
#ifdef CONFIG_SPI_FLASH_BAR
ret = write_bar(nor, addr);
ret = write_bar(nor, offset);
This change is really inobvious, the code above likely needs to be compiled out if the SPI_STACKED_PARALLEL stuff is disabled ?
In the spi_nor_erase() offset = addr; if(PARALLEL) offset/=2; so for parallel or single configuration we need to pass "offset" to write_bar() write_bar(nor, offset");
The code above likely needs to be compiled out if the SPI_STACKED_PARALLEL stuff is disabled ?
[...]
Already the code here is being checked with the flags SNOR_F_HAS_PARALLEL and SNOR_F_HAS_STACKED. Do you want to add the check SPI_STACKED_PARALLEL apart from these flags?
If I look at this change with 'git show -w' , the change looks like this:
" #ifdef CONFIG_SPI_FLASH_BAR
u32 remain_len;
ret = write_bar(nor, offset); if (ret < 0) return log_ret(ret);
remain_len = (SZ_16M * (nor->bank_curr + 1)) - offset;
if (len < remain_len)
read_len = len;
else
#endifread_len = remain_len;
if (CONFIG_IS_ENABLED(SPI_STACKED_PARALLEL)) { if (len < rem_bank_len) read_len = len; else read_len = rem_bank_len;
} if (read_len == 0) return -EIO; "
Why is there this part of code twice now, ifdeffed out differently in each case ?
" if (len < rem_bank_len) read_len = len; else read_len = rem_bank_len; "
For parallel/stacked configuration and address width the "rem_bank_len" will vary
and as we don't want to disturb the default read functionality added the ifdef separately. What would happen if both SPI_FLASH_BAR and SPI_STACKED_PARALLEL are enabled on a system that only has one SPI NOR attached (non-stacked/parallel) ? I noticed the second "copy" of the code behaves slightly differently in the else branch, so does that mean this would break such setup ?
If both SPI_FLASH_BAR and SPI_STACKED_PARALLEL are enabled, the "rem_bank_len" manipulation is done under the CONFIG_IS_ENABLED(SPI_STACKED_PARALLEL) code and this won't break any default functionality.
Thanks Venkatesh

On 12/16/24 2:58 PM, Abbarapu, Venkatesh wrote:
+++ b/drivers/mtd/spi/spi-nor-core.c @@ -1140,7 +1140,7 @@ static int spi_nor_erase(struct mtd_info *mtd, struct
erase_info *instr)
nor->spi->flags &= ~SPI_XFER_U_PAGE; } #ifdef CONFIG_SPI_FLASH_BAR
ret = write_bar(nor, addr);
ret = write_bar(nor, offset);
This change is really inobvious, the code above likely needs to be compiled out if the SPI_STACKED_PARALLEL stuff is disabled ?
In the spi_nor_erase() offset = addr; if(PARALLEL) offset/=2; so for parallel or single configuration we need to pass "offset" to write_bar() write_bar(nor, offset");
The code above likely needs to be compiled out if the SPI_STACKED_PARALLEL stuff is disabled ?
[...]
Already the code here is being checked with the flags SNOR_F_HAS_PARALLEL and SNOR_F_HAS_STACKED. Do you want to add the check SPI_STACKED_PARALLEL apart from these flags?
Yes, to compile the code out completely.
If I look at this change with 'git show -w' , the change looks like this:
" #ifdef CONFIG_SPI_FLASH_BAR
u32 remain_len;
ret = write_bar(nor, offset); if (ret < 0) return log_ret(ret);
remain_len = (SZ_16M * (nor->bank_curr + 1)) - offset;
if (len < remain_len)
read_len = len;
else
#endifread_len = remain_len;
if (CONFIG_IS_ENABLED(SPI_STACKED_PARALLEL)) { if (len < rem_bank_len) read_len = len; else read_len = rem_bank_len;
} if (read_len == 0) return -EIO; "
Why is there this part of code twice now, ifdeffed out differently in each case ?
" if (len < rem_bank_len) read_len = len; else read_len = rem_bank_len; "
For parallel/stacked configuration and address width the "rem_bank_len" will vary
and as we don't want to disturb the default read functionality added the ifdef separately. What would happen if both SPI_FLASH_BAR and SPI_STACKED_PARALLEL are enabled on a system that only has one SPI NOR attached (non-stacked/parallel) ? I noticed the second "copy" of the code behaves slightly differently in the else branch, so does that mean this would break such setup ?
If both SPI_FLASH_BAR and SPI_STACKED_PARALLEL are enabled, the "rem_bank_len" manipulation is done under the CONFIG_IS_ENABLED(SPI_STACKED_PARALLEL) code and this won't break any default functionality.
Wouldn't read_len calculation be done twice ?

-----Original Message----- From: Marek Vasut marex@denx.de Sent: Wednesday, December 18, 2024 6:39 AM To: Abbarapu, Venkatesh venkatesh.abbarapu@amd.com; u-boot@lists.denx.de; tudor.ambarus@linaro.org; j-humphreys@ti.com Cc: Simek, Michal michal.simek@amd.com; jagan@amarulasolutions.com; vigneshr@ti.com; u-kumar1@ti.com; trini@konsulko.com; seanga2@gmail.com; caleb.connolly@linaro.org; sjg@chromium.org; william.zhang@broadcom.com; stefan_b@posteo.net; quentin.schulz@cherry.de; Takahiro.Kuwano@infineon.com; p-mantena@ti.com; git (AMD-Xilinx) git@amd.com Subject: Re: [PATCH v2] mtd: spi-nor: Fix the spi_nor_read() when config SPI_STACKED_PARALLEL is enabled
On 12/16/24 2:58 PM, Abbarapu, Venkatesh wrote:
+++ b/drivers/mtd/spi/spi-nor-core.c @@ -1140,7 +1140,7 @@ static int spi_nor_erase(struct mtd_info *mtd, struct
erase_info *instr)
nor->spi->flags &= ~SPI_XFER_U_PAGE; } #ifdef CONFIG_SPI_FLASH_BAR
ret = write_bar(nor, addr);
ret = write_bar(nor, offset);
This change is really inobvious, the code above likely needs to be compiled out if the SPI_STACKED_PARALLEL stuff is disabled ?
In the spi_nor_erase() offset = addr; if(PARALLEL) offset/=2; so for parallel or single configuration we need to pass "offset" to write_bar() write_bar(nor, offset");
The code above likely needs to be compiled out if the SPI_STACKED_PARALLEL stuff is disabled ?
[...]
Already the code here is being checked with the flags SNOR_F_HAS_PARALLEL
and SNOR_F_HAS_STACKED. Do you want to add the check SPI_STACKED_PARALLEL apart from these flags?
Yes, to compile the code out completely.
Ok...Will update the patch.
If I look at this change with 'git show -w' , the change looks like this:
" #ifdef CONFIG_SPI_FLASH_BAR
u32 remain_len;
ret = write_bar(nor, offset); if (ret < 0) return log_ret(ret);
remain_len = (SZ_16M * (nor->bank_curr + 1)) - offset;
if (len < remain_len)
read_len = len;
else
#endifread_len = remain_len;
if (CONFIG_IS_ENABLED(SPI_STACKED_PARALLEL)) { if (len < rem_bank_len) read_len = len; else read_len = rem_bank_len;
} if (read_len == 0) return -EIO; "
Why is there this part of code twice now, ifdeffed out differently in each case ?
" if (len < rem_bank_len) read_len = len; else read_len = rem_bank_len; "
For parallel/stacked configuration and address width the "rem_bank_len" will vary
and as we don't want to disturb the default read functionality added the ifdef separately. What would happen if both SPI_FLASH_BAR and SPI_STACKED_PARALLEL
are
enabled on a system that only has one SPI NOR attached (non-stacked/parallel) ? I noticed the second "copy" of the code behaves slightly differently in the else branch, so does that mean this would
break such setup ?
If both SPI_FLASH_BAR and SPI_STACKED_PARALLEL are enabled, the
"rem_bank_len" manipulation is done under the CONFIG_IS_ENABLED(SPI_STACKED_PARALLEL) code and this won't break any default functionality. Wouldn't read_len calculation be done twice ?
Yes. As "rem_bank_len" will be changed based on parallel configuration, so added the additional code copy to not break the default code.
Thanks Venkatesh

On 12/18/24 10:22 AM, Abbarapu, Venkatesh wrote:
For parallel/stacked configuration and address width the "rem_bank_len" will vary
and as we don't want to disturb the default read functionality added the ifdef separately. What would happen if both SPI_FLASH_BAR and SPI_STACKED_PARALLEL
are
enabled on a system that only has one SPI NOR attached (non-stacked/parallel) ? I noticed the second "copy" of the code behaves slightly differently in the else branch, so does that mean this would
break such setup ?
If both SPI_FLASH_BAR and SPI_STACKED_PARALLEL are enabled, the
"rem_bank_len" manipulation is done under the CONFIG_IS_ENABLED(SPI_STACKED_PARALLEL) code and this won't break any default functionality. Wouldn't read_len calculation be done twice ?
Yes. As "rem_bank_len" will be changed based on parallel configuration, so added the additional code copy to not break the default code.
Can you please also update it to avoid the code duplication ?
Thank you

-----Original Message----- From: Marek Vasut marex@denx.de Sent: Wednesday, December 18, 2024 7:28 PM To: Abbarapu, Venkatesh venkatesh.abbarapu@amd.com; u-boot@lists.denx.de; tudor.ambarus@linaro.org; j-humphreys@ti.com Cc: Simek, Michal michal.simek@amd.com; jagan@amarulasolutions.com; vigneshr@ti.com; u-kumar1@ti.com; trini@konsulko.com; seanga2@gmail.com; caleb.connolly@linaro.org; sjg@chromium.org; william.zhang@broadcom.com; stefan_b@posteo.net; quentin.schulz@cherry.de; Takahiro.Kuwano@infineon.com; p-mantena@ti.com; git (AMD-Xilinx) git@amd.com Subject: Re: [PATCH v2] mtd: spi-nor: Fix the spi_nor_read() when config SPI_STACKED_PARALLEL is enabled
On 12/18/24 10:22 AM, Abbarapu, Venkatesh wrote:
For parallel/stacked configuration and address width the "rem_bank_len" will vary
and as we don't want to disturb the default read functionality added the ifdef separately. What would happen if both SPI_FLASH_BAR and
SPI_STACKED_PARALLEL
are
enabled on a system that only has one SPI NOR attached (non-stacked/parallel) ? I noticed the second "copy" of the code behaves slightly differently in the else branch, so does that mean this would
break such setup ?
If both SPI_FLASH_BAR and SPI_STACKED_PARALLEL are enabled, the
"rem_bank_len" manipulation is done under the CONFIG_IS_ENABLED(SPI_STACKED_PARALLEL) code and this won't break
any
default functionality. Wouldn't read_len calculation be done twice ?
Yes. As "rem_bank_len" will be changed based on parallel configuration, so
added the additional code copy to not break the default code. Can you please also update it to avoid the code duplication ?
The code is entirely separated out based on CONFIG_IS_ENABLED(SPI_STACKED_PARALLEL), not sure I can remove this additional code copy. Do you have any better way to avoid this code duplication?
Thanks Venkatesh
Thank you
participants (4)
-
Abbarapu, Venkatesh
-
Jon Humphreys
-
Marek Vasut
-
Venkatesh Yadav Abbarapu