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Diffstat (limited to 'target/linux/xburst/patches-3.3/0013-MMC-JZ4740-Added-support-for-CPU-frequency-changing.patch')
-rw-r--r--target/linux/xburst/patches-3.3/0013-MMC-JZ4740-Added-support-for-CPU-frequency-changing.patch129
1 files changed, 129 insertions, 0 deletions
diff --git a/target/linux/xburst/patches-3.3/0013-MMC-JZ4740-Added-support-for-CPU-frequency-changing.patch b/target/linux/xburst/patches-3.3/0013-MMC-JZ4740-Added-support-for-CPU-frequency-changing.patch
new file mode 100644
index 0000000..f42d67a
--- /dev/null
+++ b/target/linux/xburst/patches-3.3/0013-MMC-JZ4740-Added-support-for-CPU-frequency-changing.patch
@@ -0,0 +1,129 @@
+From b95144c1b702f98c7902c75beb83f323701eb7c5 Mon Sep 17 00:00:00 2001
+From: Maarten ter Huurne <maarten@treewalker.org>
+Date: Sun, 19 Jun 2011 10:57:18 +0200
+Subject: [PATCH 13/21] MMC: JZ4740: Added support for CPU frequency changing.
+
+The MSC device clock is stopped before the frequency change.
+After the change a new divider is computed and the clock is restarted.
+Also the frequency change is postponed if an I/O operation is in progress.
+---
+ drivers/mmc/host/jz4740_mmc.c | 69 +++++++++++++++++++++++++++++++++++++++-
+ 1 files changed, 67 insertions(+), 2 deletions(-)
+
+--- a/drivers/mmc/host/jz4740_mmc.c
++++ b/drivers/mmc/host/jz4740_mmc.c
+@@ -23,6 +23,7 @@
+ #include <linux/delay.h>
+ #include <linux/scatterlist.h>
+ #include <linux/clk.h>
++#include <linux/cpufreq.h>
+
+ #include <linux/bitops.h>
+ #include <linux/gpio.h>
+@@ -685,6 +686,60 @@ static void jz4740_mmc_enable_sdio_irq(s
+ jz4740_mmc_set_irq_enabled(host, JZ_MMC_IRQ_SDIO, enable);
+ }
+
++#ifdef CONFIG_CPU_FREQ
++
++static struct jz4740_mmc_host *cpufreq_host;
++
++static int jz4740_mmc_cpufreq_transition(struct notifier_block *nb,
++ unsigned long val, void *data)
++{
++ /* TODO: We only have to take action when the PLL freq changes:
++ the main dividers have no influence on the MSC device clock. */
++
++ if (val == CPUFREQ_PRECHANGE) {
++ mmc_claim_host(cpufreq_host->mmc);
++ clk_disable(cpufreq_host->clk);
++ } else if (val == CPUFREQ_POSTCHANGE) {
++ struct mmc_ios *ios = &cpufreq_host->mmc->ios;
++ if (ios->clock)
++ jz4740_mmc_set_clock_rate(cpufreq_host, ios->clock);
++ if (ios->power_mode != MMC_POWER_OFF)
++ clk_enable(cpufreq_host->clk);
++ mmc_release_host(cpufreq_host->mmc);
++ }
++ return 0;
++}
++
++static struct notifier_block jz4740_mmc_cpufreq_nb = {
++ .notifier_call = jz4740_mmc_cpufreq_transition,
++};
++
++static inline int jz4740_mmc_cpufreq_register(struct jz4740_mmc_host *host)
++{
++ cpufreq_host = host;
++ return cpufreq_register_notifier(&jz4740_mmc_cpufreq_nb,
++ CPUFREQ_TRANSITION_NOTIFIER);
++}
++
++static inline void jz4740_mmc_cpufreq_unregister(void)
++{
++ cpufreq_unregister_notifier(&jz4740_mmc_cpufreq_nb,
++ CPUFREQ_TRANSITION_NOTIFIER);
++}
++
++#else
++
++static inline int jz4740_mmc_cpufreq_register(struct jz4740_mmc_host *host)
++{
++ return 0;
++}
++
++static inline void jz4740_mmc_cpufreq_unregister(void)
++{
++}
++
++#endif
++
+ static const struct mmc_host_ops jz4740_mmc_ops = {
+ .request = jz4740_mmc_request,
+ .set_ios = jz4740_mmc_set_ios,
+@@ -834,11 +889,18 @@ static int __devinit jz4740_mmc_probe(st
+ goto err_free_host;
+ }
+
++ ret = jz4740_mmc_cpufreq_register(host);
++ if (ret) {
++ dev_err(&pdev->dev,
++ "Failed to register cpufreq transition notifier\n");
++ goto err_clk_put;
++ }
++
+ host->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!host->mem) {
+ ret = -ENOENT;
+ dev_err(&pdev->dev, "Failed to get base platform memory\n");
+- goto err_clk_put;
++ goto err_cpufreq_unreg;
+ }
+
+ host->mem = request_mem_region(host->mem->start,
+@@ -846,7 +908,7 @@ static int __devinit jz4740_mmc_probe(st
+ if (!host->mem) {
+ ret = -EBUSY;
+ dev_err(&pdev->dev, "Failed to request base memory region\n");
+- goto err_clk_put;
++ goto err_cpufreq_unreg;
+ }
+
+ host->base = ioremap_nocache(host->mem->start, resource_size(host->mem));
+@@ -929,6 +991,8 @@ err_iounmap:
+ iounmap(host->base);
+ err_release_mem_region:
+ release_mem_region(host->mem->start, resource_size(host->mem));
++err_cpufreq_unreg:
++ jz4740_mmc_cpufreq_unregister();
+ err_clk_put:
+ clk_put(host->clk);
+ err_free_host:
+@@ -958,6 +1022,7 @@ static int __devexit jz4740_mmc_remove(s
+ iounmap(host->base);
+ release_mem_region(host->mem->start, resource_size(host->mem));
+
++ jz4740_mmc_cpufreq_unregister();
+ clk_put(host->clk);
+
+ platform_set_drvdata(pdev, NULL);