diff options
Diffstat (limited to 'target/linux/s3c24xx/patches-2.6.24/1323-GTA01-use-slow-SD-clock-when-gps-on.patch.patch')
| -rw-r--r-- | target/linux/s3c24xx/patches-2.6.24/1323-GTA01-use-slow-SD-clock-when-gps-on.patch.patch | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/target/linux/s3c24xx/patches-2.6.24/1323-GTA01-use-slow-SD-clock-when-gps-on.patch.patch b/target/linux/s3c24xx/patches-2.6.24/1323-GTA01-use-slow-SD-clock-when-gps-on.patch.patch new file mode 100644 index 0000000000..3e16c6edfe --- /dev/null +++ b/target/linux/s3c24xx/patches-2.6.24/1323-GTA01-use-slow-SD-clock-when-gps-on.patch.patch @@ -0,0 +1,161 @@ +From d944934bbddc281938fb1905a69e35c0581937c2 Mon Sep 17 00:00:00 2001 +From: Mike Westerhof <mwester@dls.net> +Date: Thu, 13 Nov 2008 20:39:36 +0000 +Subject: [PATCH] GTA01-use-slow-SD-clock-when-gps-on.patch + +This patch implements Andy Green's SD clock slow-down code +for the GTA01 device. + +Signed-off-by: Mike Westerhof <mwester@dls.net> +--- + arch/arm/mach-s3c2410/mach-gta01.c | 8 ++++++ + drivers/mmc/host/s3cmci.c | 43 ++++++++++++++++++++++++++++++++++- + drivers/mmc/host/s3cmci.h | 1 + + include/asm-arm/arch-s3c2410/mci.h | 1 + + 4 files changed, 51 insertions(+), 2 deletions(-) + +diff --git a/arch/arm/mach-s3c2410/mach-gta01.c b/arch/arm/mach-s3c2410/mach-gta01.c +index a364b76..c0817dc 100644 +--- a/arch/arm/mach-s3c2410/mach-gta01.c ++++ b/arch/arm/mach-s3c2410/mach-gta01.c +@@ -75,6 +75,8 @@ + #include <asm/plat-s3c24xx/neo1973.h> + #include <asm/arch-s3c2410/neo1973-pm-gsm.h> + ++#include "../plat-s3c24xx/neo1973_pm_gps.h" ++ + #include <linux/jbt6k74.h> + + static struct map_desc gta01_iodesc[] __initdata = { +@@ -432,9 +434,15 @@ static void gta01_mmc_set_power(unsigned char power_mode, unsigned short vdd) + } + } + ++static int gta01_mmc_use_slow(void) ++{ ++ return neo1973_pm_gps_is_on(); ++} ++ + static struct s3c24xx_mci_pdata gta01_mmc_cfg = { + .gpio_detect = GTA01_GPIO_nSD_DETECT, + .set_power = >a01_mmc_set_power, ++ .use_slow = >a01_mmc_use_slow, + .ocr_avail = MMC_VDD_165_195|MMC_VDD_20_21| + MMC_VDD_21_22|MMC_VDD_22_23|MMC_VDD_23_24| + MMC_VDD_24_25|MMC_VDD_25_26|MMC_VDD_26_27| +diff --git a/drivers/mmc/host/s3cmci.c b/drivers/mmc/host/s3cmci.c +index 8f88721..87d24b2 100644 +--- a/drivers/mmc/host/s3cmci.c ++++ b/drivers/mmc/host/s3cmci.c +@@ -59,6 +59,23 @@ module_param(sd_max_clk, int, 0644); + static int sd_idleclk; /* disallow idle clock by default */ + module_param(sd_idleclk, int, 0644); + ++/* ++ * Slow SD clock rate ++ * ++ * you can override this on kernel commandline using ++ * ++ * s3cmci.sd_slow_ratio=8 ++ * ++ * for example. ++ * ++ * A platform callback is used to decide effective clock rate. If not ++ * defined, then the max is used, if defined and the callback returns ++ * nonzero, the rate is divided by this factor. ++ */ ++ ++static int sd_slow_ratio = 8; ++module_param(sd_slow_ratio, int, 0644); ++ + /* used to stash real idleclk state in suspend: we force it to run in there */ + static int suspend_sd_idleclk; + +@@ -252,7 +269,7 @@ static inline void do_pio_read(struct s3cmci_host *host) + void __iomem *from_ptr; + + /* write real prescaler to host, it might be set slow to fix */ +- writel(host->prescaler, host->base + S3C2410_SDIPRE); ++ writel(host->sdipre, host->base + S3C2410_SDIPRE); + + from_ptr = host->base + host->sdidata; + +@@ -755,7 +772,7 @@ static void finalize_request(struct s3cmci_host *host) + cmd->resp[3] = readl(host->base + S3C2410_SDIRSP3); + + /* reset clock speed, as it could still be set low for */ +- writel(host->prescaler, host->base + S3C2410_SDIPRE); ++ writel(host->sdipre, host->base + S3C2410_SDIPRE); + + if (cmd->error) + debug_as_failure = 1; +@@ -1032,6 +1049,7 @@ static void s3cmci_send_request(struct mmc_host *mmc) + struct s3cmci_host *host = mmc_priv(mmc); + struct mmc_request *mrq = host->mrq; + struct mmc_command *cmd = host->cmd_is_stop?mrq->stop:mrq->cmd; ++ int pre; + + host->ccnt++; + #ifdef CONFIG_MMC_DEBUG +@@ -1073,6 +1091,26 @@ static void s3cmci_send_request(struct mmc_host *mmc) + + } + ++ /* establish the correct prescaler depending on the sd_slow_ratio */ ++ ++ if ((sd_slow_ratio > 1) && ++ host->pdata->use_slow && (host->pdata->use_slow)()) { ++ /* compute the slower speed */ ++ pre = host->prescaler * sd_slow_ratio; ++ if (pre > 255) ++ pre = 255; ++ } else { ++ /* use the normal speed */ ++ pre = host->prescaler; ++ } ++ ++ if (host->sdipre != pre) { ++ dbg(host, dbg_conf, "prescaler changed: %d -> %d\n", ++ (int)host->sdipre, pre); ++ host->sdipre = pre; ++ writel(host->sdipre, host->base + S3C2410_SDIPRE); ++ } ++ + __s3cmci_enable_clock(host); + s3cmci_send_command(host, cmd); + enable_irq(host->irq); +@@ -1138,6 +1176,7 @@ static void s3cmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) + if (mci_psc > 255) + mci_psc = 255; + host->prescaler = mci_psc; ++ host->sdipre = mci_psc; + + writel(host->prescaler, host->base + S3C2410_SDIPRE); + +diff --git a/drivers/mmc/host/s3cmci.h b/drivers/mmc/host/s3cmci.h +index 9644b45..11974ff 100644 +--- a/drivers/mmc/host/s3cmci.h ++++ b/drivers/mmc/host/s3cmci.h +@@ -32,6 +32,7 @@ struct s3cmci_host { + unsigned long clk_div; + unsigned long real_rate; + u8 prescaler; ++ u8 sdipre; + + int is2440; + unsigned sdiimsk; +diff --git a/include/asm-arm/arch-s3c2410/mci.h b/include/asm-arm/arch-s3c2410/mci.h +index 24e6cd1..f087229 100644 +--- a/include/asm-arm/arch-s3c2410/mci.h ++++ b/include/asm-arm/arch-s3c2410/mci.h +@@ -8,6 +8,7 @@ struct s3c24xx_mci_pdata { + unsigned int do_dma; + void (*set_power)(unsigned char power_mode, + unsigned short vdd); ++ int (*use_slow)(void); + }; + + #endif /* _ARCH_NCI_H */ +-- +1.5.6.5 + |