From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tony Lindgren Subject: Re: [PATCH v2 1/5] OMAP3: PM: HSMMC: force MMC module reset on boot Date: Fri, 5 Dec 2008 16:27:47 -0800 Message-ID: <20081206002747.GQ9714@atomide.com> References: <1228148566-9358-1-git-send-email-khilman@deeprootsystems.com> <1228148566-9358-2-git-send-email-khilman@deeprootsystems.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mho-01-bos.mailhop.org ([63.208.196.178]:55095 "EHLO mho-01-bos.mailhop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755329AbYLFA1t (ORCPT ); Fri, 5 Dec 2008 19:27:49 -0500 Content-Disposition: inline In-Reply-To: <1228148566-9358-2-git-send-email-khilman@deeprootsystems.com> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Kevin Hilman Cc: linux-omap@vger.kernel.org * Kevin Hilman [081201 08:23]: > 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. Pushing to l-o tree, and adding omap mmc queue for mainline. Tony > > Signed-off-by: Kevin Hilman > --- > arch/arm/mach-omap2/devices.c | 85 +++++++++++++++++++++++++++++++++++++++++ > 1 files changed, 85 insertions(+), 0 deletions(-) > > diff --git a/arch/arm/mach-omap2/devices.c b/arch/arm/mach-omap2/devices.c > index 241e418..423647e 100644 > --- a/arch/arm/mach-omap2/devices.c > +++ b/arch/arm/mach-omap2/devices.c > @@ -14,6 +14,7 @@ > #include > #include > #include > +#include > > #include > #include > @@ -358,6 +359,89 @@ static inline void omap_init_sha1_md5(void) { } > > /*-------------------------------------------------------------------------*/ > > +#ifdef CONFIG_ARCH_OMAP3 > + > +#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 bootloader) may prevent retention > + * or OFF-mode. This is especially important in cases where the > + * MMC driver is not enabled, _or_ built as a module. > + * > + * 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, nr_controllers = cpu_is_omap34xx() ? OMAP34XX_NR_MMC : > + OMAP24XX_NR_MMC; > + > + for (i = 0; i < nr_controllers; i++) { > + u32 v, base = 0; > + struct clk *iclk, *fclk; > + struct device *dev = &dummy_pdev.dev; > + > + switch (i) { > + case 0: > + base = OMAP2_MMC1_BASE; > + break; > + case 1: > + base = OMAP2_MMC2_BASE; > + break; > + case 2: > + base = OMAP3_MMC3_BASE; > + break; > + } > + > + 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 + MMCHS_SYSCONFIG); > + v = omap_readl(base + MMCHS_SYSSTATUS); > + while (!(omap_readl(base + 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 +561,7 @@ 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@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html