From 7437cfa532842ce75189826742bddf1ba137f58e Mon Sep 17 00:00:00 2001 From: Ulf Hansson Date: Wed, 18 Jan 2012 09:17:27 +0100 Subject: [PATCH] ARM: 7280/1: mmc: mmci: Cache MMCICLOCK and MMCIPOWER register Instead of reading a register value everytime we need to apply a new value for it, maintain a cached copy for it. This also means we are able to skip writes that are not needed. Tested-by: Linus Walleij Signed-off-by: Ulf Hansson Signed-off-by: Linus Walleij Signed-off-by: Russell King --- drivers/mmc/host/mmci.c | 41 +++++++++++++++++++++++++++++------------ drivers/mmc/host/mmci.h | 3 ++- 2 files changed, 31 insertions(+), 13 deletions(-) diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c index 1f8832699cdf..f36d8b8c891f 100644 --- a/drivers/mmc/host/mmci.c +++ b/drivers/mmc/host/mmci.c @@ -118,6 +118,28 @@ static struct variant_data variant_ux500v2 = { .signal_direction = true, }; +/* + * This must be called with host->lock held + */ +static void mmci_write_clkreg(struct mmci_host *host, u32 clk) +{ + if (host->clk_reg != clk) { + host->clk_reg = clk; + writel(clk, host->base + MMCICLOCK); + } +} + +/* + * This must be called with host->lock held + */ +static void mmci_write_pwrreg(struct mmci_host *host, u32 pwr) +{ + if (host->pwr_reg != pwr) { + host->pwr_reg = pwr; + writel(pwr, host->base + MMCIPOWER); + } +} + /* * This must be called with host->lock held */ @@ -165,7 +187,7 @@ static void mmci_set_clkreg(struct mmci_host *host, unsigned int desired) if (host->mmc->ios.bus_width == MMC_BUS_WIDTH_8) clk |= MCI_ST_8BIT_BUS; - writel(clk, host->base + MMCICLOCK); + mmci_write_clkreg(host, clk); } static void @@ -846,14 +868,13 @@ static int mmci_pio_write(struct mmci_host *host, char *buffer, unsigned int rem */ if (variant->sdio && mmc_card_sdio(host->mmc->card)) { + u32 clk; if (count < 8) - writel(readl(host->base + MMCICLOCK) & - ~variant->clkreg_enable, - host->base + MMCICLOCK); + clk = host->clk_reg & ~variant->clkreg_enable; else - writel(readl(host->base + MMCICLOCK) | - variant->clkreg_enable, - host->base + MMCICLOCK); + clk = host->clk_reg | variant->clkreg_enable; + + mmci_write_clkreg(host, clk); } /* @@ -1114,11 +1135,7 @@ static void mmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) spin_lock_irqsave(&host->lock, flags); mmci_set_clkreg(host, ios->clock); - - if (host->pwr != pwr) { - host->pwr = pwr; - writel(pwr, host->base + MMCIPOWER); - } + mmci_write_pwrreg(host, pwr); spin_unlock_irqrestore(&host->lock, flags); diff --git a/drivers/mmc/host/mmci.h b/drivers/mmc/host/mmci.h index 89eb2e3556d3..d437ccf62d6b 100644 --- a/drivers/mmc/host/mmci.h +++ b/drivers/mmc/host/mmci.h @@ -179,7 +179,8 @@ struct mmci_host { unsigned int mclk; unsigned int cclk; - u32 pwr; + u32 pwr_reg; + u32 clk_reg; struct mmci_platform_data *plat; struct variant_data *variant; -- 2.34.1