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Diffstat (limited to 'target/linux/s3c24xx/patches-2.6.24/1292-fix-glamo-mci-slow-clock-until-first-bulk.patch.patch')
-rw-r--r--target/linux/s3c24xx/patches-2.6.24/1292-fix-glamo-mci-slow-clock-until-first-bulk.patch.patch261
1 files changed, 261 insertions, 0 deletions
diff --git a/target/linux/s3c24xx/patches-2.6.24/1292-fix-glamo-mci-slow-clock-until-first-bulk.patch.patch b/target/linux/s3c24xx/patches-2.6.24/1292-fix-glamo-mci-slow-clock-until-first-bulk.patch.patch
new file mode 100644
index 0000000..642f545
--- /dev/null
+++ b/target/linux/s3c24xx/patches-2.6.24/1292-fix-glamo-mci-slow-clock-until-first-bulk.patch.patch
@@ -0,0 +1,261 @@
+From 9e7ba57b104e9293f746342b7450b10d5fa0c4cd Mon Sep 17 00:00:00 2001
+From: Andy Green <andy@openmoko.com>
+Date: Mon, 22 Sep 2008 22:38:03 +0100
+Subject: [PATCH] fix-glamo-mci-slow-clock-until-first-bulk.patch
+
+This patch adds another module parameter to glamo-mci which sets the
+SD Card clock rate used inbetween powering the card and the completion of
+the first bulk transfer. You can set it from kernel commandline like this.
+
+glamo_mci.sd_post_power_clock=1000000
+
+The period between changing the power state and the first bulk transfer
+completion is critical because larger SDHC cards take longer to initialize
+before they can service the bulk transfer, and the Glamo MMC unit has a
+fixed timeout length of a maximum of 4095 x 16 x SD Card clocks. Large
+cards like 8GB Sandisk SDHC are not ready before this timeout is used up
+at default 16MHz.
+
+Subsequently, the card can handle 16MHz SD Clock and timeout durations
+okay.
+
+By default this patch operates the SD Clock at only 1MHz until the first
+bulk transfer is completed after each powerup action from the MCI stack. It
+also keeps the SD Clock running during this time, and disables the SD Clock
+if the card is not present and the MCI stack removes power.
+
+Signed-off-by: Andy Green <andy@openmoko.com>
+---
+ drivers/mfd/glamo/glamo-mci.c | 108 +++++++++++++++++++++++++----------------
+ drivers/mfd/glamo/glamo-mci.h | 2 +
+ 2 files changed, 68 insertions(+), 42 deletions(-)
+
+diff --git a/drivers/mfd/glamo/glamo-mci.c b/drivers/mfd/glamo/glamo-mci.c
+index 3eece08..cff43db 100644
+--- a/drivers/mfd/glamo/glamo-mci.c
++++ b/drivers/mfd/glamo/glamo-mci.c
+@@ -74,6 +74,23 @@ static int sd_slow_ratio = 8;
+ module_param(sd_slow_ratio, int, 0644);
+
+ /*
++ * Post-power SD clock rate
++ *
++ * you can override this on kernel commandline using
++ *
++ * glamo_mci.sd_post_power_clock=1000000
++ *
++ * for example
++ *
++ * After changing power to card, clock is held at this rate until first bulk
++ * transfer completes
++ */
++
++static int sd_post_power_clock = 1000000;
++module_param(sd_post_power_clock, int, 0644);
++
++
++/*
+ * SD Signal drive strength
+ *
+ * you can override this on kernel commandline using
+@@ -240,21 +257,35 @@ static void __glamo_mci_fix_card_div(struct glamo_mci_host *host, int div)
+ writew(readw(glamo_mci_def_pdata.pglamo->base +
+ GLAMO_REG_CLOCK_GEN5_1) & (~GLAMO_CLOCK_GEN51_EN_DIV_TCLK),
+ glamo_mci_def_pdata.pglamo->base + GLAMO_REG_CLOCK_GEN5_1);
+- } else {
+- /* set the nearest prescaler factor
+- *
+- * register shared with SCLK divisor -- no chance of race because
+- * we don't use sensor interface
+- */
+- writew_dly((readw(glamo_mci_def_pdata.pglamo->base +
+- GLAMO_REG_CLOCK_GEN8) & 0xff00) | div,
+- glamo_mci_def_pdata.pglamo->base + GLAMO_REG_CLOCK_GEN8);
+- /* enable clock to divider input */
+- writew_dly(readw(glamo_mci_def_pdata.pglamo->base +
+- GLAMO_REG_CLOCK_GEN5_1) | GLAMO_CLOCK_GEN51_EN_DIV_TCLK,
+- glamo_mci_def_pdata.pglamo->base + GLAMO_REG_CLOCK_GEN5_1);
++
++ goto done;
+ }
+
++ if (host->force_slow_during_powerup)
++ div = host->clk_rate / sd_post_power_clock;
++ else
++ if (host->pdata->glamo_mci_use_slow)
++ if ((host->pdata->glamo_mci_use_slow)())
++ div = div * sd_slow_ratio;
++
++ if (div > 255)
++ div = 255;
++
++ /*
++ * set the nearest prescaler factor
++ *
++ * register shared with SCLK divisor -- no chance of race because
++ * we don't use sensor interface
++ */
++ writew_dly((readw(glamo_mci_def_pdata.pglamo->base +
++ GLAMO_REG_CLOCK_GEN8) & 0xff00) | div,
++ glamo_mci_def_pdata.pglamo->base + GLAMO_REG_CLOCK_GEN8);
++ /* enable clock to divider input */
++ writew_dly(readw(glamo_mci_def_pdata.pglamo->base +
++ GLAMO_REG_CLOCK_GEN5_1) | GLAMO_CLOCK_GEN51_EN_DIV_TCLK,
++ glamo_mci_def_pdata.pglamo->base + GLAMO_REG_CLOCK_GEN5_1);
++
++done:
+ spin_unlock_irqrestore(&clock_lock, flags);
+ }
+
+@@ -284,7 +315,7 @@ static int __glamo_mci_set_card_clock(struct glamo_mci_host *host, int freq,
+ if (division)
+ *division = 0xff;
+
+- if (!sd_idleclk)
++ if (!sd_idleclk && !host->force_slow_during_powerup)
+ /* clock off */
+ __glamo_mci_fix_card_div(host, -1);
+ }
+@@ -327,6 +358,10 @@ static void glamo_mci_irq(unsigned int irq, struct irq_desc *desc)
+ goto done;
+ }
+
++ /* disable the initial slow start after first bulk transfer */
++ if (host->force_slow_during_powerup)
++ host->force_slow_during_powerup--;
++
+ if (host->pio_active == XFER_READ)
+ do_pio_read(host);
+
+@@ -341,7 +376,7 @@ static void glamo_mci_irq(unsigned int irq, struct irq_desc *desc)
+ host->cmd_is_stop = 0;
+ }
+
+- if (!sd_idleclk)
++ if (!sd_idleclk && !host->force_slow_during_powerup)
+ /* clock off */
+ __glamo_mci_fix_card_div(host, -1);
+
+@@ -357,7 +392,6 @@ static int glamo_mci_send_command(struct glamo_mci_host *host,
+ {
+ u8 u8a[6];
+ u16 fire = 0;
+- u16 timeout = 0xfff; /* max glamo MMC timeout, in units of 16 clocks */
+
+ /* if we can't do it, reject as busy */
+ if (!readw_dly(host->base + GLAMO_REG_MMC_RB_STAT1) &
+@@ -467,15 +501,9 @@ static int glamo_mci_send_command(struct glamo_mci_host *host,
+ fire |= GLAMO_FIRE_MMC_CC_BASIC; /* "basic command" */
+ break;
+ }
+- /* enforce timeout, clipping at default 65520 clocks if larger */
+- if (cmd->data)
+- /* so long as there is one... */
+- if (cmd->data->timeout_clks &&
+- /* ... and it is not longer than we can handle */
+- (cmd->data->timeout_clks <= 0xffff))
+- timeout = cmd->data->timeout_clks >> 4; /* / 16 clks */
+
+- writew(timeout, host->base + GLAMO_REG_MMC_TIMEOUT);
++ /* always largest timeout */
++ writew(0xfff, host->base + GLAMO_REG_MMC_TIMEOUT);
+
+ /* Generate interrupt on txfer */
+ writew_dly((readw_dly(host->base + GLAMO_REG_MMC_BASIC) & 0x3e) |
+@@ -576,14 +604,7 @@ static void glamo_mci_send_request(struct mmc_host *mmc)
+ /* resume requested clock rate
+ * scale it down by sd_slow_ratio if platform requests it
+ */
+- if (host->pdata->glamo_mci_use_slow)
+- if ((host->pdata->glamo_mci_use_slow)())
+- __glamo_mci_fix_card_div(host, host->clk_div *
+- sd_slow_ratio);
+- else
+- __glamo_mci_fix_card_div(host, host->clk_div);
+- else
+- __glamo_mci_fix_card_div(host, host->clk_div);
++ __glamo_mci_fix_card_div(host, host->clk_div);
+
+ if (glamo_mci_send_command(host, cmd))
+ goto bail;
+@@ -633,6 +654,7 @@ static void glamo_mci_send_request(struct mmc_host *mmc)
+ goto done;
+ if (!(cmd->data->flags & (MMC_DATA_READ | MMC_DATA_WRITE)))
+ goto done;
++
+ /*
+ * Otherwise can can use the interrupt as async completion --
+ * if there is read data coming, or we wait for write data to complete,
+@@ -676,7 +698,7 @@ done:
+ host->mrq = NULL;
+ mmc_request_done(host->mmc, cmd->mrq);
+ bail:
+- if (!sd_idleclk)
++ if (!sd_idleclk && !host->force_slow_during_powerup)
+ /* stop the clock to card */
+ __glamo_mci_fix_card_div(host, -1);
+ }
+@@ -718,6 +740,12 @@ static void glamo_mci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
+ switch(ios->power_mode) {
+ case MMC_POWER_ON:
+ case MMC_POWER_UP:
++ /*
++ * we should use very slow clock until first bulk
++ * transfer completes OK
++ */
++ host->force_slow_during_powerup = 1;
++
+ if (host->vdd_current != ios->vdd) {
+ host->pdata->glamo_set_mci_power(ios->power_mode,
+ ios->vdd);
+@@ -734,6 +762,9 @@ static void glamo_mci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
+ default:
+ if (host->power_mode_current == MMC_POWER_OFF)
+ break;
++ /* never want clocking with dead card */
++ __glamo_mci_fix_card_div(host, -1);
++
+ glamo_engine_disable(glamo_mci_def_pdata.pglamo,
+ GLAMO_ENGINE_MMC);
+ host->pdata->glamo_set_mci_power(MMC_POWER_OFF, 0);
+@@ -751,7 +782,7 @@ static void glamo_mci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
+ if (powering)
+ msleep(1);
+
+- if (!sd_idleclk)
++ if (!sd_idleclk && !host->force_slow_during_powerup)
+ /* stop the clock to card, because we are idle until transfer */
+ __glamo_mci_fix_card_div(host, -1);
+
+@@ -954,14 +985,7 @@ static int glamo_mci_suspend(struct platform_device *dev, pm_message_t state)
+ * make sure the clock was running during suspend and consequently
+ * resume
+ */
+- if (host->pdata->glamo_mci_use_slow)
+- if ((host->pdata->glamo_mci_use_slow)())
+- __glamo_mci_fix_card_div(host, host->clk_div *
+- sd_slow_ratio);
+- else
+- __glamo_mci_fix_card_div(host, host->clk_div);
+- else
+- __glamo_mci_fix_card_div(host, host->clk_div);
++ __glamo_mci_fix_card_div(host, host->clk_div);
+
+ /* we are going to do more commands to override this in
+ * mmc_suspend_host(), so we need to change sd_idleclk for the
+diff --git a/drivers/mfd/glamo/glamo-mci.h b/drivers/mfd/glamo/glamo-mci.h
+index f3f170e..38f6376 100644
+--- a/drivers/mfd/glamo/glamo-mci.h
++++ b/drivers/mfd/glamo/glamo-mci.h
+@@ -44,6 +44,8 @@ struct glamo_mci_host {
+ unsigned long real_rate;
+ u8 prescaler;
+
++ int force_slow_during_powerup;
++
+ unsigned sdiimsk;
+ int dodma;
+
+--
+1.5.6.5
+
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