* Kevin Hilman <khilman@xxxxxxxxxxxxxxxxxxx> [081126 16:07]:
> The bootloader may leave the MMC in a state which prevents hitting
> retention. Even when MMC is not compiled in, each MMC module needs to
> be forced into reset.
>
> Signed-off-by: Kevin Hilman <khilman@xxxxxxxxxxxxxxxxxxx>
> ---
> arch/arm/mach-omap2/devices.c | 76 +++++++++++++++++++++++++++++++++++++++++
> 1 files changed, 76 insertions(+), 0 deletions(-)
>
> diff --git a/arch/arm/mach-omap2/devices.c b/arch/arm/mach-omap2/devices.c
> index 241e418..196de4e 100644
> --- a/arch/arm/mach-omap2/devices.c
> +++ b/arch/arm/mach-omap2/devices.c
> @@ -14,6 +14,7 @@
> #include <linux/init.h>
> #include <linux/platform_device.h>
> #include <linux/io.h>
> +#include <linux/clk.h>
>
> #include <mach/hardware.h>
> #include <asm/mach-types.h>
> @@ -358,6 +359,80 @@ static inline void omap_init_sha1_md5(void) { }
>
> /*-------------------------------------------------------------------------*/
>
> +#ifdef CONFIG_ARCH_OMAP3
> +
> +#define MMCHS1 (L4_34XX_BASE + 0x9C000)
> +#define MMCHS2 (L4_34XX_BASE + 0xB4000)
> +#define MMCHS3 (L4_34XX_BASE + 0xAD000)
These are already in plat-omap/include/mach/mmc.h, how about just
include it? Then you can have a switch statement like we already have
for omap2_init_mmc?
> +#define MAX_MMC 3
This too
> +#define MMCHS_SYSCONFIG 0x0010
> +#define MMCHS_SYSCONFIG_SWRESET (1 << 1)
> +#define MMCHS_SYSSTATUS 0x0014
> +#define MMCHS_SYSSTATUS_RESETDONE (1 << 0)
> +
> +static struct platform_device dummy_pdev = {
> + .dev = {
> + .bus = &platform_bus_type,
> + },
> +};
> +
> +/**
> + * omap_hsmmc_reset() - Full reset of each HS-MMC controller
> + *
> + * Ensure that each MMC controller is fully reset. Controllers
> + * left in an unknown state (by bootloaer) may prevent retention
> + * or OFF-mode. This is especially important in cases where the
> + * MMC driver is not enabled, _or_ built as a module.
Should say bootloader above :)
Regards,
Tony
> + * In order for reset to work, interface, functional and debounce
> + * clocks must be enabled. The debounce clock comes from func_32k_clk
> + * and is not under SW control, so we only enable i- and f-clocks.
> + **/
> +static void __init omap_hsmmc_reset(void)
> +{
> + u32 i, base[MAX_MMC] = {MMCHS1, MMCHS2, MMCHS3};
> +
> + for (i = 0; i < MAX_MMC; i++) {
> + u32 v;
> + struct clk *iclk, *fclk;
> + struct device *dev = &dummy_pdev.dev;
> +
> + dummy_pdev.id = i;
> + iclk = clk_get(dev, "mmchs_ick");
> + if (iclk && clk_enable(iclk))
> + iclk = NULL;
> +
> + fclk = clk_get(dev, "mmchs_fck");
> + if (fclk && clk_enable(fclk))
> + fclk = NULL;
> +
> + if (!iclk || !fclk) {
> + printk(KERN_WARNING
> + "%s: Unable to enable clocks for MMC%d, "
> + "cannot reset.\n", __func__, i);
> + break;
> + }
> +
> + omap_writel(MMCHS_SYSCONFIG_SWRESET, base[i] + MMCHS_SYSCONFIG);
> + v = omap_readl(base[i] + MMCHS_SYSSTATUS);
> + while (!(omap_readl(base[i] + MMCHS_SYSSTATUS) &
> + MMCHS_SYSSTATUS_RESETDONE))
> + cpu_relax();
> +
> + if (fclk) {
> + clk_disable(fclk);
> + clk_put(fclk);
> + }
> + if (iclk) {
> + clk_disable(iclk);
> + clk_put(iclk);
> + }
> + }
> +}
> +#else
> +static inline void omap_hsmmc_reset(void) {}
> +#endif
> +
> #if defined(CONFIG_MMC_OMAP) || defined(CONFIG_MMC_OMAP_MODULE) || \
> defined(CONFIG_MMC_OMAP_HS) || defined(CONFIG_MMC_OMAP_HS_MODULE)
>
> @@ -477,6 +552,7 @@ static int __init omap2_init_devices(void)
> /* please keep these calls, and their implementations above,
> * in alphabetical order so they're easier to sort through.
> */
> + omap_hsmmc_reset();
> omap_init_camera();
> omap_init_mbox();
> omap_init_mcspi();
> --
> 1.6.0.3
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-omap" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
