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authorUlf Hansson <ulf.hansson@stericsson.com>2012-01-18 09:17:27 +0100
committerRussell King <rmk+kernel@arm.linux.org.uk>2012-02-02 17:02:15 +0000
commit7437cfa532842ce75189826742bddf1ba137f58e (patch)
treea668a44a7c54b9f8e73c816831ad0958cc61fc18 /drivers/mmc/host/mmci.c
parent393e5e24165d0bef60489ecd0baef085e9af2e5a (diff)
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 <linus.walleij@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@stericsson.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'drivers/mmc/host/mmci.c')
-rw-r--r--drivers/mmc/host/mmci.c41
1 files changed, 29 insertions, 12 deletions
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index 1f8832699cd..f36d8b8c891 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -121,6 +121,28 @@ static struct variant_data variant_ux500v2 = {
/*
* 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
+ */
static void mmci_set_clkreg(struct mmci_host *host, unsigned int desired)
{
struct variant_data *variant = host->variant;
@@ -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);