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Diffstat (limited to 'target/linux/s3c24xx/patches-2.6.26/0218-debug-add-glamo-drive-strength-module-param.patch.patch')
-rwxr-xr-xtarget/linux/s3c24xx/patches-2.6.26/0218-debug-add-glamo-drive-strength-module-param.patch.patch167
1 files changed, 167 insertions, 0 deletions
diff --git a/target/linux/s3c24xx/patches-2.6.26/0218-debug-add-glamo-drive-strength-module-param.patch.patch b/target/linux/s3c24xx/patches-2.6.26/0218-debug-add-glamo-drive-strength-module-param.patch.patch
new file mode 100755
index 0000000000..dd0fcff816
--- /dev/null
+++ b/target/linux/s3c24xx/patches-2.6.26/0218-debug-add-glamo-drive-strength-module-param.patch.patch
@@ -0,0 +1,167 @@
+From e1bc0be9f95559ae154d24b353e404c781798da1 Mon Sep 17 00:00:00 2001
+From: Andy Green <andy@openmoko.com>
+Date: Fri, 25 Jul 2008 23:06:20 +0100
+Subject: [PATCH] debug-add-glamo-drive-strength-module-param.patch
+ Suggested-by: Werner Almesberger <werner@openmoko.org>
+
+This patch allows users to control two additional settings
+in Glamo MCI driver from kernel commandline or module
+parameters.
+
+
+First is Glamo drive strength on SD IOs including CLK.
+This ranges from 0 (weakest) to 3 (strongest).
+
+echo 0 > /sys/module/glamo_mci/parameters/sd_drive
+
+(Changes to this take effect on next SD Card transaction)
+
+or, from kernel commandline
+
+glamo_mci.sd_drive=0
+
+On tests here with 0 strength, communication to SD card
+(shipped 512MB Sandisk) seemed fine, and a dd of 10MB
+urandom had the same md5 when written to cache as after
+a reboot. I set the default to 2.
+
+
+Second is whether we allow SD_CLK when the SD interface
+is idle.
+
+# stop the clock when we are idle (default)
+echo 0 > /sys/module/glamo_mci/parameters/sd_idleclk
+
+# run the SD clock all the time
+echo 1 > /sys/module/glamo_mci/parameters/sd_idleclk
+
+(changes take effect on next SD Card transaction)
+
+From kernel commandline, eg:
+
+glamo_mci.sd_idleclk=1
+
+Normally you don't want to run the SD Clock all the time.
+
+
+Signed-off-by: Andy Green <andy@openmoko.com>
+---
+ drivers/mfd/glamo/glamo-mci.c | 59 +++++++++++++++++++++++++++++++---------
+ 1 files changed, 45 insertions(+), 14 deletions(-)
+
+diff --git a/drivers/mfd/glamo/glamo-mci.c b/drivers/mfd/glamo/glamo-mci.c
+index 93f4074..4615033 100644
+--- a/drivers/mfd/glamo/glamo-mci.c
++++ b/drivers/mfd/glamo/glamo-mci.c
+@@ -56,6 +56,32 @@ static void glamo_mci_send_request(struct mmc_host *mmc);
+ static int sd_max_clk = 50000000 / 3;
+ module_param(sd_max_clk, int, 0644);
+
++/*
++ * SD Signal drive strength
++ *
++ * you can override this on kernel commandline using
++ *
++ * glamo_mci.sd_drive=0
++ *
++ * for example
++ */
++
++static int sd_drive = 2;
++module_param(sd_drive, int, 0644);
++
++/*
++ * SD allow SD clock to run while idle
++ *
++ * you can override this on kernel commandline using
++ *
++ * glamo_mci.sd_idleclk=0
++ *
++ * for example
++ */
++
++static int sd_idleclk = 0; /* disallow idle clock by default */
++module_param(sd_idleclk, int, 0644);
++
+
+
+ unsigned char CRC7(u8 * pu8, int cnt)
+@@ -239,7 +265,9 @@ static int __glamo_mci_set_card_clock(struct glamo_mci_host *host, int freq,
+ if (division)
+ *division = 0xff;
+
+- __glamo_mci_fix_card_div(host, -1); /* clock off */
++ if (!sd_idleclk)
++ /* clock off */
++ __glamo_mci_fix_card_div(host, -1);
+ }
+
+ return real_rate;
+@@ -294,8 +322,9 @@ static void glamo_mci_irq(unsigned int irq, struct irq_desc *desc)
+ host->cmd_is_stop = 0;
+ }
+
+- /* clock off */
+- __glamo_mci_fix_card_div(host, -1);
++ if (!sd_idleclk)
++ /* clock off */
++ __glamo_mci_fix_card_div(host, -1);
+
+ done:
+ host->complete_what = COMPLETION_NONE;
+@@ -428,12 +457,10 @@ static int glamo_mci_send_command(struct glamo_mci_host *host,
+ } else
+ writew(0xfff, host->base + GLAMO_REG_MMC_TIMEOUT);
+
+- /* Generate interrupt on txfer; drive strength max */
+- writew_dly((readw_dly(host->base + GLAMO_REG_MMC_BASIC) & 0xfe) |
++ /* Generate interrupt on txfer */
++ writew_dly((readw_dly(host->base + GLAMO_REG_MMC_BASIC) & 0x3e) |
+ 0x0800 | GLAMO_BASIC_MMC_NO_CLK_RD_WAIT |
+- GLAMO_BASIC_MMC_EN_COMPL_INT |
+- GLAMO_BASIC_MMC_EN_DR_STR0 |
+- GLAMO_BASIC_MMC_EN_DR_STR1,
++ GLAMO_BASIC_MMC_EN_COMPL_INT | (sd_drive << 6),
+ host->base + GLAMO_REG_MMC_BASIC);
+
+ /* send the command out on the wire */
+@@ -620,8 +647,9 @@ done:
+ host->mrq = NULL;
+ mmc_request_done(host->mmc, cmd->mrq);
+ bail:
+- /* stop the clock to card */
+- __glamo_mci_fix_card_div(host, -1);
++ if (!sd_idleclk)
++ /* stop the clock to card */
++ __glamo_mci_fix_card_div(host, -1);
+ }
+
+ static void glamo_mci_request(struct mmc_host *mmc, struct mmc_request *mrq)
+@@ -687,8 +715,9 @@ static void glamo_mci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
+ host->real_rate = __glamo_mci_set_card_clock(host, ios->clock, &div);
+ host->clk_div = div;
+
+- /* stop the clock to card, because we are idle until transfer */
+- __glamo_mci_fix_card_div(host, -1);
++ if (!sd_idleclk)
++ /* stop the clock to card, because we are idle until transfer */
++ __glamo_mci_fix_card_div(host, -1);
+
+ if ((ios->power_mode == MMC_POWER_ON) ||
+ (ios->power_mode == MMC_POWER_UP)) {
+@@ -705,8 +734,10 @@ static void glamo_mci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
+ if (host->bus_width == MMC_BUS_WIDTH_4)
+ n = GLAMO_BASIC_MMC_EN_4BIT_DATA;
+ writew_dly((readw_dly(host->base + GLAMO_REG_MMC_BASIC) &
+- (~GLAMO_BASIC_MMC_EN_4BIT_DATA)) | n,
+- host->base + GLAMO_REG_MMC_BASIC);
++ (~(GLAMO_BASIC_MMC_EN_4BIT_DATA |
++ GLAMO_BASIC_MMC_EN_DR_STR0 |
++ GLAMO_BASIC_MMC_EN_DR_STR1))) | n |
++ sd_drive << 6, host->base + GLAMO_REG_MMC_BASIC);
+ }
+
+
+--
+1.5.6.3
+