diff options
Diffstat (limited to 'arch/arm/mach-tegra/cpu-tegra.c')
| -rw-r--r-- | arch/arm/mach-tegra/cpu-tegra.c | 48 |
1 files changed, 47 insertions, 1 deletions
diff --git a/arch/arm/mach-tegra/cpu-tegra.c b/arch/arm/mach-tegra/cpu-tegra.c index ceb52db1e2f1..627bf0f4262e 100644 --- a/arch/arm/mach-tegra/cpu-tegra.c +++ b/arch/arm/mach-tegra/cpu-tegra.c @@ -49,6 +49,8 @@ static struct cpufreq_frequency_table freq_table[] = { #define NUM_CPUS 2 static struct clk *cpu_clk; +static struct clk *pll_x_clk; +static struct clk *pll_p_clk; static struct clk *emc_clk; static unsigned long target_cpu_speed[NUM_CPUS]; @@ -71,6 +73,42 @@ static unsigned int tegra_getspeed(unsigned int cpu) return rate; } +static int tegra_cpu_clk_set_rate(unsigned long rate) +{ + int ret; + + /* + * Take an extra reference to the main pll so it doesn't turn + * off when we move the cpu off of it + */ + clk_prepare_enable(pll_x_clk); + + ret = clk_set_parent(cpu_clk, pll_p_clk); + if (ret) { + pr_err("Failed to switch cpu to clock pll_p\n"); + goto out; + } + + if (rate == clk_get_rate(pll_p_clk)) + goto out; + + ret = clk_set_rate(pll_x_clk, rate); + if (ret) { + pr_err("Failed to change pll_x to %lu\n", rate); + goto out; + } + + ret = clk_set_parent(cpu_clk, pll_x_clk); + if (ret) { + pr_err("Failed to switch cpu to clock pll_x\n"); + goto out; + } + +out: + clk_disable_unprepare(pll_x_clk); + return ret; +} + static int tegra_update_cpu_speed(unsigned long rate) { int ret = 0; @@ -101,7 +139,7 @@ static int tegra_update_cpu_speed(unsigned long rate) freqs.old, freqs.new); #endif - ret = clk_set_rate(cpu_clk, freqs.new * 1000); + ret = tegra_cpu_clk_set_rate(freqs.new * 1000); if (ret) { pr_err("cpu-tegra: Failed to set cpu frequency to %d kHz\n", freqs.new); @@ -183,6 +221,14 @@ static int tegra_cpu_init(struct cpufreq_policy *policy) if (IS_ERR(cpu_clk)) return PTR_ERR(cpu_clk); + pll_x_clk = clk_get_sys(NULL, "pll_x"); + if (IS_ERR(pll_x_clk)) + return PTR_ERR(pll_x_clk); + + pll_p_clk = clk_get_sys(NULL, "pll_p"); + if (IS_ERR(pll_p_clk)) + return PTR_ERR(pll_p_clk); + emc_clk = clk_get_sys("cpu", "emc"); if (IS_ERR(emc_clk)) { clk_put(cpu_clk); |