From b987c4b2c9c9db2393f4c089e63d1734301214e5 Mon Sep 17 00:00:00 2001 From: Sekhar Nori Date: Tue, 20 Jul 2010 16:46:51 +0530 Subject: [PATCH] davinci: am18x/da850/omap-l138: keep async clock constant with cpufreq Keep PLL0 SYSCLK3 at a constant rate of 100MHz. This enables the AEMIF timing to remain valid even as the PLL0 output is changed by cpufreq driver to save power. Signed-off-by: Sekhar Nori Signed-off-by: Kevin Hilman --- arch/arm/mach-davinci/board-da850-evm.c | 2 +- arch/arm/mach-davinci/da850.c | 10 +++++++++- arch/arm/mach-davinci/include/mach/da8xx.h | 2 +- 3 files changed, 11 insertions(+), 3 deletions(-) diff --git a/arch/arm/mach-davinci/board-da850-evm.c b/arch/arm/mach-davinci/board-da850-evm.c index f5f9472..c2800a9 100644 --- a/arch/arm/mach-davinci/board-da850-evm.c +++ b/arch/arm/mach-davinci/board-da850-evm.c @@ -787,7 +787,7 @@ static __init void da850_evm_init(void) if (ret) pr_warning("da850_evm_init: rtc setup failed: %d\n", ret); - ret = da850_register_cpufreq(); + ret = da850_register_cpufreq("pll0_sysclk3"); if (ret) pr_warning("da850_evm_init: cpufreq registration failed: %d\n", ret); diff --git a/arch/arm/mach-davinci/da850.c b/arch/arm/mach-davinci/da850.c index 6932d80..5af7cfb 100644 --- a/arch/arm/mach-davinci/da850.c +++ b/arch/arm/mach-davinci/da850.c @@ -86,6 +86,8 @@ static struct clk pll0_sysclk3 = { .parent = &pll0_clk, .flags = CLK_PLL, .div_reg = PLLDIV3, + .set_rate = davinci_set_sysclk_rate, + .maxrate = 100000000, }; static struct clk pll0_sysclk4 = { @@ -929,10 +931,16 @@ static struct platform_device da850_cpufreq_device = { .dev = { .platform_data = &cpufreq_info, }, + .id = -1, }; -int __init da850_register_cpufreq(void) +int __init da850_register_cpufreq(char *async_clk) { + /* cpufreq driver can help keep an "async" clock constant */ + if (async_clk) + clk_add_alias("async", da850_cpufreq_device.name, + async_clk, NULL); + return platform_device_register(&da850_cpufreq_device); } diff --git a/arch/arm/mach-davinci/include/mach/da8xx.h b/arch/arm/mach-davinci/include/mach/da8xx.h index 3c07059..2c3f418 100644 --- a/arch/arm/mach-davinci/include/mach/da8xx.h +++ b/arch/arm/mach-davinci/include/mach/da8xx.h @@ -78,7 +78,7 @@ int da8xx_register_lcdc(struct da8xx_lcdc_platform_data *pdata); int da8xx_register_mmcsd0(struct davinci_mmc_config *config); void __init da8xx_register_mcasp(int id, struct snd_platform_data *pdata); int da8xx_register_rtc(void); -int da850_register_cpufreq(void); +int da850_register_cpufreq(char *async_clk); int da8xx_register_cpuidle(void); void __iomem * __init da8xx_get_mem_ctlr(void); int da850_register_pm(struct platform_device *pdev); -- 2.7.4