Re: [PATCH 02/22] arm: kirkwood: 88f6281: Detect CONFIG_SYS_TCLK from SAR register

[michael]

Am 2022-08-23 07:02, schrieb Stefan Roese:

Hi Michael,

On 17.08.22 21:37, Michael Walle wrote:

From: Pali Rohár <p...@kernel.org>

Bit 21 in SAR register specifies if TCLK is running at 166 MHz or 200 MHz.

This information is undocumented in public Marvell Kirkwood Functional
Specifications [2], but is available in Linux v3.15 kirkwood code [1].

Commit 8ac303d49f89 ("arm: kirkwood: Do not overwrite CONFIG_SYS_TCLK") broke support for Marvell 88F6281 SoCs because it was expected that all those SoCs have TCLK running at 200 MHz as specified in Marvell 88F6281

Hardware Specifications [3].

Fix broken support for 88F6281 by detecting CONFIG_SYS_TCLK from SAR
register, like it was doing Linux v3.15.

[1] - https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tree/arch/arm/mach-kirkwood/common.c?h=v3.15#n542 [2] - https://web.archive.org/web/20130730091033/http://www.marvell.com/embedded-processors/kirkwood/assets/FS_88F6180_9x_6281_OpenSource.pdf [3] - https://web.archive.org/web/20120620073511/http://www.marvell.com/embedded-processors/kirkwood/assets/HW_88F6281_OpenSource.pdf

Fixes: 8ac303d49f89 ("arm: kirkwood: Do not overwrite CONFIG_SYS_TCLK")

Signed-off-by: Pali Rohár <p...@kernel.org>

I've applied your patch series on master (from yesterday) and see
these error(s):

$ make ds109_defconfig
$ make -sj
...
In file included from ./arch/arm/include/asm/arch/config.h:18,
                 from include/configs/mv-common.h:58,
                 from include/configs/ds109.h:14,
                 from include/config.h:4,
                 from include/common.h:16,
                 from board/Synology/ds109/ds109.c:8:
board/Synology/ds109/ds109.c: In function 'reset_misc':
./arch/arm/include/asm/arch/kw88f6281.h:18:43: warning: implicit
declaration of function 'readl' [-Wimplicit-function-declaration]
   18 | #define CONFIG_SYS_TCLK
((readl(CONFIG_SAR_REG) & BIT(21)) ? \
      |                                           ^~~~~

include/configs/mv-common.h:36:41: note: in expansion of macro 'CONFIG_SYS_TCLK'

   36 | #define CONFIG_SYS_NS16550_CLK          CONFIG_SYS_TCLK
      |                                         ^~~~~~~~~~~~~~~
board/Synology/ds109/ds109.c:111:36: note: in expansion of macro
'CONFIG_SYS_NS16550_CLK'

111 | CONFIG_SYS_NS16550_CLK, 9600);

      |                                    ^~~~~~~~~~~~~~~~~~~~~~
/opt/kernel.org/gcc-11.1.0-nolibc/arm-linux-gnueabi/bin/arm-linux-gnueabi-ld.bfd:
board/Synology/ds109/ds109.o: in function `reset_misc':
/home/stefan/git/u-boot/u-boot-marvell/board/Synology/ds109/ds109.c:111:
undefined reference to `readl'
make: *** [Makefile:1823: u-boot] Error 1

Could you please take a look and fix this?

I guess soc.h should also include <asm/io.h> because now it is
using that hidden readl().

Pali?

-michael