[U-Boot] [PATCH] ppc4xx: Don't fixup NOR flash node size on Ebony
Don't update size in "reg" property of NOR FLASH device tree nodes. This leads to a problem with this NOR flash setup, where chip-select 0 is connected to 512KiB SRAM *and* 512KiB NOR flash. And with this fixup-code, the size of the NOR flash node is changed from 512KiB to 1MiB which leads to a crash in the Linux MTD driver.
Signed-off-by: Stefan Roese sr@denx.de Cc: Detlev Zundel dzu@denx.de --- include/configs/ebony.h | 8 ++++++++ 1 files changed, 8 insertions(+), 0 deletions(-)
diff --git a/include/configs/ebony.h b/include/configs/ebony.h index 10f425d..eb58240 100644 --- a/include/configs/ebony.h +++ b/include/configs/ebony.h @@ -117,6 +117,14 @@ #define CONFIG_SYS_FLASH_ADDR0 0x5555 #define CONFIG_SYS_FLASH_ADDR1 0x2aaa #define CONFIG_SYS_FLASH_WORD_SIZE unsigned char +/* + * Don't update size in "reg" property of NOR FLASH device tree nodes. + * This leads to a problem with this NOR flash setup, where + * chip-select 0 is connected to 512KiB SRAM *and* 512KiB NOR flash. + * And with this fixup-code, the size of the NOR flash node is changed + * from 512KiB to 1MiB which leads to a crash in the Linux MTD driver. + */ +#undef CONFIG_FDT_FIXUP_NOR_FLASH_SIZE
#ifdef CONFIG_ENV_IS_IN_FLASH #define CONFIG_ENV_SECT_SIZE 0x10000 /* size of one complete sector */
Dear Stefan Roese,
In message 1284555484-27269-1-git-send-email-sr@denx.de you wrote:
Don't update size in "reg" property of NOR FLASH device tree nodes. This leads to a problem with this NOR flash setup, where chip-select 0 is connected to 512KiB SRAM *and* 512KiB NOR flash. And with this fixup-code, the size of the NOR flash node is changed from 512KiB to 1MiB which leads to a crash in the Linux MTD driver.
Signed-off-by: Stefan Roese sr@denx.de Cc: Detlev Zundel dzu@denx.de
include/configs/ebony.h | 8 ++++++++ 1 files changed, 8 insertions(+), 0 deletions(-)
diff --git a/include/configs/ebony.h b/include/configs/ebony.h index 10f425d..eb58240 100644 --- a/include/configs/ebony.h +++ b/include/configs/ebony.h @@ -117,6 +117,14 @@ #define CONFIG_SYS_FLASH_ADDR0 0x5555 #define CONFIG_SYS_FLASH_ADDR1 0x2aaa #define CONFIG_SYS_FLASH_WORD_SIZE unsigned char +/*
- Don't update size in "reg" property of NOR FLASH device tree nodes.
- This leads to a problem with this NOR flash setup, where
- chip-select 0 is connected to 512KiB SRAM *and* 512KiB NOR flash.
- And with this fixup-code, the size of the NOR flash node is changed
- from 512KiB to 1MiB which leads to a crash in the Linux MTD driver.
- */
+#undef CONFIG_FDT_FIXUP_NOR_FLASH_SIZE
Sorry, but NAK.
Even if connected to the same chip select, NOR flash and SRAM are different devices, which are described by different properties in the device tree and which have separate addresses and sizes.
The "reg" property of NOR FLASH device tree nodes *should* be updated with the correct size of the NOR flash as determined by the CFI driver; on this board, this should be 512 KiB.
Both the bd_info command and the device tree should report a NOR flash size of 512 KiB.
The SRAM size is completely independent of that. As we don't provide auto-sizing for the sram, the board config file should contain (read: needs to get fixed to contain) the correct CONFIG_SYS_SRAM_BASE and CONFIG_SYS_SRAM_SIZE settings (with CONFIG_SYS_SRAM_SIZE = 512 KiB).
Both the bd_info command and the device tree should report a SRAM size of 512 KiB.
Best regards,
Wolfgang Denk
Hi Wolfgang,
On Wednesday 15 September 2010 15:14:03 Wolfgang Denk wrote:
+/*
- Don't update size in "reg" property of NOR FLASH device tree nodes.
- This leads to a problem with this NOR flash setup, where
- chip-select 0 is connected to 512KiB SRAM *and* 512KiB NOR flash.
- And with this fixup-code, the size of the NOR flash node is changed
- from 512KiB to 1MiB which leads to a crash in the Linux MTD driver.
- */
+#undef CONFIG_FDT_FIXUP_NOR_FLASH_SIZE
Sorry, but NAK.
Even if connected to the same chip select, NOR flash and SRAM are different devices, which are described by different properties in the device tree and which have separate addresses and sizes.
Correct.
The "reg" property of NOR FLASH device tree nodes *should* be updated with the correct size of the NOR flash as determined by the CFI driver; on this board, this should be 512 KiB.
This value of 512KiB is already present in the NOR flash device tree node.
Both the bd_info command and the device tree should report a NOR flash size of 512 KiB.
bdinfo shows 4.5MiB of flashsize, since Ebony has additional flash devices at different chip-selects. There are additional device tree nodes to describe these NOR flash devices as well. The total of all NOR flash device tree nodes will be 4.5MiB as well, using this patch. With out this patch it is 5MiB.
The SRAM size is completely independent of that. As we don't provide auto-sizing for the sram, the board config file should contain (read: needs to get fixed to contain) the correct CONFIG_SYS_SRAM_BASE and CONFIG_SYS_SRAM_SIZE settings (with CONFIG_SYS_SRAM_SIZE = 512 KiB).
Both the bd_info command and the device tree should report a SRAM size of 512 KiB.
My patch doesn't touch any SRAM lated stuff. It fixes a real issue, where Ebony currently crashes upon Linux booting trying to map/detect NOR flash devices at an inaccessible memory region.
Perhaps I described the change best. I'll try again:
This patch disables the PPC4xx specific device-tree-blob fixup code, which is enabled per default for all AMCC/APM eval boards, that writes the chip-select size into the size of the "reg" property of the NOR flash device tree nodes. This fixup code is intended for boards with multiple flash configurations, passing the detected flash size in the device tree node to the Linux kernel. On Ebony this code doesn't work correctly, since it has an 512KiB SRAM and an 512KiB NOR flash connected to one chip-select. This code updates incorrectly 1MiB of chip-select size into the NOR flash device tree node.
I hope this is clearer now.
Cheers, Stefan
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Dear Stefan Roese,
In message 201009151543.02284.sr@denx.de you wrote:
The "reg" property of NOR FLASH device tree nodes *should* be updated with the correct size of the NOR flash as determined by the CFI driver; on this board, this should be 512 KiB.
This value of 512KiB is already present in the NOR flash device tree node.
It should be updated in any case using the values as determined by the CFI flash driver.
Both the bd_info command and the device tree should report a NOR flash size of 512 KiB.
bdinfo shows 4.5MiB of flashsize, since Ebony has additional flash devices at
OK.
different chip-selects. There are additional device tree nodes to describe these NOR flash devices as well. The total of all NOR flash device tree nodes will be 4.5MiB as well, using this patch. With out this patch it is 5MiB.
Then there is a bug somewhere, because you seem to add 4 + 1 MiB flash sizes when the real sizes are only 4 MiB + 512 KiB.
The SRAM size is completely independent of that. As we don't provide auto-sizing for the sram, the board config file should contain (read: needs to get fixed to contain) the correct CONFIG_SYS_SRAM_BASE and CONFIG_SYS_SRAM_SIZE settings (with CONFIG_SYS_SRAM_SIZE = 512 KiB).
Both the bd_info command and the device tree should report a SRAM size of 512 KiB.
My patch doesn't touch any SRAM lated stuff. It fixes a real issue, where Ebony currently crashes upon Linux booting trying to map/detect NOR flash devices at an inaccessible memory region.
I wanted to point out that the SRAM settings are missing and need fixing, too.
This patch disables the PPC4xx specific device-tree-blob fixup code, which is enabled per default for all AMCC/APM eval boards, that writes the chip-select size into the size of the "reg" property of the NOR flash device tree nodes.
Ah! That's the bug, then. You must not write any map size, but only the real flash device size as determined by the CFI driver.
This fixup code is intended for boards with multiple flash configurations, passing the detected flash size in the device tree node to the Linux kernel. On Ebony this code doesn't work correctly, since it has an 512KiB SRAM and an 512KiB NOR flash connected to one chip-select. This code updates incorrectly 1MiB of chip-select size into the NOR flash device tree node.
It does not work correctly because you are incorrectly using the size of the chip select mapping when you should be using the flash device size instead. Please fix this problem.
Best regards,
Wolfgang Denk
participants (2)
-
Stefan Roese -
Wolfgang Denk