[PATCH 0/3] ARM: imx6: fix up buggy CCM_CSCMR1 register

Dirk Behme dirk.behme at de.bosch.com
Fri Jul 12 05:15:43 EDT 2013


On 10.07.2013 17:21, Shawn Guo wrote:
> There is a defect in bits 22 and 21 of i.MX6 CCM_CSCMR1 register.  These
> two bits are inverted between read and write.  That said, bit field
> CCM_CSCMR1[22-20] (aclk/emi_podf on imx6q/dl and lcdif_pix_podf on
> imx6sl) will be something as below between read and write.
>
>    read    write    divider
>     000     110       1
>     001     111       2
>     010     100       3
>     011     101       4
>     100     010       5
>     101     011       6
>     110     000       7
>     111     001       8
>
> To work around this hardware defect, every single read/modify/write
> sequence on the register will require a fix-up (invert bits 22 and 21)
> before writing the value into register.  As there are dividers and
> multiplexers defined in the register, we choose to inherit the basic
> clk-divider and clk-mux and override the functions which writes register
> with a fix-up hooked in.
>
> Shawn
>
> Liu Ying (3):
>    ARM: imx: add common clock support for fixup div
>    ARM: imx: add common clock support for fixup mux
>    ARM: imx6: change some clocks to fixup clocks
>
>   arch/arm/mach-imx/Makefile        |    3 +-
>   arch/arm/mach-imx/clk-fixup-div.c |  129 +++++++++++++++++++++++++++++++++++++
>   arch/arm/mach-imx/clk-fixup-mux.c |  107 ++++++++++++++++++++++++++++++
>   arch/arm/mach-imx/clk-imx6q.c     |   24 +++----
>   arch/arm/mach-imx/clk-imx6sl.c    |   20 +++---
>   arch/arm/mach-imx/clk.c           |   26 ++++++++
>   arch/arm/mach-imx/clk.h           |   10 +++
>   7 files changed, 296 insertions(+), 23 deletions(-)
>   create mode 100644 arch/arm/mach-imx/clk-fixup-div.c
>   create mode 100644 arch/arm/mach-imx/clk-fixup-mux.c

For the whole series:

Acked-by: Dirk Behme <dirk.behme at de.bosch.com>

Thanks

Dirk





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