[U-Boot] [PATCH] p1022ds: use weak CFI flash accessors when DIU is enabled
Wolfgang Denk
wd at denx.de
Thu Sep 16 23:13:38 CEST 2010
Dear Timur Tabi,
In message <1284667695-10887-1-git-send-email-timur at freescale.com> you wrote:
> On the Freescale P1022, the DIU and the LBC share address pins, which means
> that when the DIU is active (e.g. the console is on the DVI display), NOR flash
> cannot be accessed. So we use the weak accessor function feature of the CFI
> flash code to temporarily switch the pin mux from LBC to DIU whenever we want
> to read or write flash. This has a significant performance penalty, but it's
I think the description is wrong - don't you switch from DIU to LBC
for flash access?
> +/* Variables used by the DIU/LBC switching code. It's safe to makes these
> + * global, because the DIU requires DDR, so we'll only run this code after
> + * relocation.
> + */
Incorrect multiline comment format.
> +/**
> + * set_mux_to_lbc - disable the DIU so that we can read/write to elbc
Incorrect multiline comment format. Please check and fix globally.
> + /* Switch the muxes only if they're currently set to DIU mode */
> + if ((in_be32(&gur->pmuxcr) & PMUXCR_ELBCDIU_MASK) == PMUXCR_ELBCDIU_NOR16) {
Line too long. Please check and fix globally.
> diff --git a/include/configs/P1022DS.h b/include/configs/P1022DS.h
> index d518c69..a4910a6 100644
> --- a/include/configs/P1022DS.h
> +++ b/include/configs/P1022DS.h
> @@ -190,6 +190,12 @@
> #define CONFIG_VGA_AS_SINGLE_DEVICE
> #define CONFIG_VIDEO_LOGO
> #define CONFIG_VIDEO_BMP_LOGO
> +#define CONFIG_CFI_FLASH_USE_WEAK_ACCESSORS
> +/*
> + * With CONFIG_CFI_FLASH_USE_WEAK_ACCESSORS, flash I/O is really slow, so
> + * disable empty flash sector detection, which is I/O-intensive.
> + */
> +#undef CONFIG_SYS_FLASH_EMPTY_INFO
"#ifdef CONFIG_CFI_FLASH_USE_WEAK_ACCESSORS" / "#endif" arount the
#undef ?
Best regards,
Wolfgang Denk
--
DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel
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