[CPUFREQ] EXYNOS4210: cpufreq code is changed for stable working

This patch is modify code for stable working
1. Remove unused register access code
2. Change sequence for frequency changing

Signed-off-by: Jaecheol Lee <jc.lee@samsung.com>
Signed-off-by: Jonghwan Choi <jhbird.choi@samsung.com>
Signed-off-by: Jongpill Lee <boyko.lee@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Dave Jones <davej@redhat.com>

1 files changed, 65 insertions, 36 deletions

diff --git a/drivers/cpufreq/exynos4210-cpufreq.c b/drivers/cpufreq/exynos4210-cpufreq.c
index ba579e0a5c3f..a0af2d4448a9 100644
--- a/drivers/cpufreq/exynos4210-cpufreq.c
+++ b/drivers/cpufreq/exynos4210-cpufreq.c
@@ -36,6 +36,10 @@ static struct regulator *arm_regulator;
 
 static struct cpufreq_freqs freqs;
 
+struct cpufreq_clkdiv {
+        unsigned int clkdiv;
+};
+
 static unsigned int locking_frequency;
 static bool frequency_locked;
 static DEFINE_MUTEX(cpufreq_lock);
@@ -44,6 +48,8 @@ enum cpufreq_level_index {
         L0, L1, L2, L3, L4, CPUFREQ_LEVEL_END,
 };
 
+static struct cpufreq_clkdiv exynos4_clkdiv_table[CPUFREQ_LEVEL_END];
+
 static struct cpufreq_frequency_table exynos4_freq_table[] = {
         {L0, 1200*1000},
         {L1, 1000*1000},
@@ -155,20 +161,7 @@ static void exynos4_set_clkdiv(unsigned int div_index)
 
         /* Change Divider - CPU0 */
 
-        tmp = __raw_readl(S5P_CLKDIV_CPU);
-
-        tmp &= ~(S5P_CLKDIV_CPU0_CORE_MASK | S5P_CLKDIV_CPU0_COREM0_MASK |
-                S5P_CLKDIV_CPU0_COREM1_MASK | S5P_CLKDIV_CPU0_PERIPH_MASK |
-                S5P_CLKDIV_CPU0_ATB_MASK | S5P_CLKDIV_CPU0_PCLKDBG_MASK |
-                S5P_CLKDIV_CPU0_APLL_MASK);
-
-        tmp |= ((clkdiv_cpu0[div_index][0] << S5P_CLKDIV_CPU0_CORE_SHIFT) |
-                (clkdiv_cpu0[div_index][1] << S5P_CLKDIV_CPU0_COREM0_SHIFT) |
-                (clkdiv_cpu0[div_index][2] << S5P_CLKDIV_CPU0_COREM1_SHIFT) |
-                (clkdiv_cpu0[div_index][3] << S5P_CLKDIV_CPU0_PERIPH_SHIFT) |
-                (clkdiv_cpu0[div_index][4] << S5P_CLKDIV_CPU0_ATB_SHIFT) |
-                (clkdiv_cpu0[div_index][5] << S5P_CLKDIV_CPU0_PCLKDBG_SHIFT) |
-                (clkdiv_cpu0[div_index][6] << S5P_CLKDIV_CPU0_APLL_SHIFT));
+        tmp = exynos4_clkdiv_table[div_index].clkdiv;
 
         __raw_writel(tmp, S5P_CLKDIV_CPU);
 
@@ -233,14 +226,12 @@ static void exynos4_set_frequency(unsigned int old_index, unsigned int new_index
         unsigned int tmp;
 
         if (old_index > new_index) {
-                /* The frequency changing to L0 needs to change apll */
-                if (freqs.new == exynos4_freq_table[L0].frequency) {
-                        /* 1. Change the system clock divider values */
-                        exynos4_set_clkdiv(new_index);
-
-                        /* 2. Change the apll m,p,s value */
-                        exynos4_set_apll(new_index);
-                } else {
+                /*
+                 * L1/L3, L2/L4 Level change require
+                 * to only change s divider value
+                 */
+                if (((old_index == L3) && (new_index == L1)) ||
+                                ((old_index == L4) && (new_index == L2))) {
                         /* 1. Change the system clock divider values */
                         exynos4_set_clkdiv(new_index);
 
@@ -249,18 +240,20 @@ static void exynos4_set_frequency(unsigned int old_index, unsigned int new_index
                         tmp &= ~(0x7 << 0);
                         tmp |= (exynos4_apll_pms_table[new_index] & 0x7);
                         __raw_writel(tmp, S5P_APLL_CON0);
-                }
-        }
-
-        else if (old_index < new_index) {
-                /* The frequency changing from L0 needs to change apll */
-                if (freqs.old == exynos4_freq_table[L0].frequency) {
-                        /* 1. Change the apll m,p,s value */
-                        exynos4_set_apll(new_index);
-
-                        /* 2. Change the system clock divider values */
-                        exynos4_set_clkdiv(new_index);
                 } else {
+                        /* Clock Configuration Procedure */
+                        /* 1. Change the system clock divider values */
+                        exynos4_set_clkdiv(new_index);
+                        /* 2. Change the apll m,p,s value */
+                        exynos4_set_apll(new_index);
+                }
+        } else if (old_index < new_index) {
+                /*
+                 * L1/L3, L2/L4 Level change require
+                 * to only change s divider value
+                 */
+                if (((old_index == L1) && (new_index == L3)) ||
+                                ((old_index == L2) && (new_index == L4))) {
                         /* 1. Change just s value in apll m,p,s value */
                         tmp = __raw_readl(S5P_APLL_CON0);
                         tmp &= ~(0x7 << 0);
@@ -269,6 +262,12 @@ static void exynos4_set_frequency(unsigned int old_index, unsigned int new_index
 
                         /* 2. Change the system clock divider values */
                         exynos4_set_clkdiv(new_index);
+                } else {
+                        /* Clock Configuration Procedure */
+                        /* 1. Change the apll m,p,s value */
+                        exynos4_set_apll(new_index);
+                        /* 2. Change the system clock divider values */
+                        exynos4_set_clkdiv(new_index);
                 }
         }
 }
@@ -320,14 +319,14 @@ static int exynos4_target(struct cpufreq_policy *policy,
         /* Clock Configuration Procedure */
         exynos4_set_frequency(old_index, index);
 
+        cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
+
         /* control regulator */
         if (freqs.new < freqs.old) {
                 /* Voltage down */
                 regulator_set_voltage(arm_regulator, arm_volt, arm_volt);
         }
 
-        cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
-
 out:
         mutex_unlock(&cpufreq_lock);
         return err;
@@ -438,7 +437,12 @@ static int exynos4_cpufreq_cpu_init(struct cpufreq_policy *policy)
          * Each cpu is bound to the same speed.
          * So the affected cpu is all of the cpus.
          */
-        cpumask_setall(policy->cpus);
+        if (!cpu_online(1)) {
+                cpumask_copy(policy->related_cpus, cpu_possible_mask);
+                cpumask_copy(policy->cpus, cpu_online_mask);
+        } else {
+                cpumask_setall(policy->cpus);
+        }
 
         ret = cpufreq_frequency_table_cpuinfo(policy, exynos4_freq_table);
         if (ret)
@@ -477,6 +481,9 @@ static struct cpufreq_driver exynos4_driver = {
 
 static int __init exynos4_cpufreq_init(void)
 {
+        int i;
+        unsigned int tmp;
+
         cpu_clk = clk_get(NULL, "armclk");
         if (IS_ERR(cpu_clk))
                 return PTR_ERR(cpu_clk);
@@ -503,6 +510,28 @@ static int __init exynos4_cpufreq_init(void)
 
         register_pm_notifier(&exynos4_cpufreq_nb);
 
+        tmp = __raw_readl(S5P_CLKDIV_CPU);
+
+        for (i = L0; i <  CPUFREQ_LEVEL_END; i++) {
+                tmp &= ~(S5P_CLKDIV_CPU0_CORE_MASK |
+                         S5P_CLKDIV_CPU0_COREM0_MASK |
+                         S5P_CLKDIV_CPU0_COREM1_MASK |
+                         S5P_CLKDIV_CPU0_PERIPH_MASK |
+                         S5P_CLKDIV_CPU0_ATB_MASK |
+                         S5P_CLKDIV_CPU0_PCLKDBG_MASK |
+                         S5P_CLKDIV_CPU0_APLL_MASK);
+
+                tmp |= ((clkdiv_cpu0[i][0] << S5P_CLKDIV_CPU0_CORE_SHIFT) |
+                        (clkdiv_cpu0[i][1] << S5P_CLKDIV_CPU0_COREM0_SHIFT) |
+                        (clkdiv_cpu0[i][2] << S5P_CLKDIV_CPU0_COREM1_SHIFT) |
+                        (clkdiv_cpu0[i][3] << S5P_CLKDIV_CPU0_PERIPH_SHIFT) |
+                        (clkdiv_cpu0[i][4] << S5P_CLKDIV_CPU0_ATB_SHIFT) |
+                        (clkdiv_cpu0[i][5] << S5P_CLKDIV_CPU0_PCLKDBG_SHIFT) |
+                        (clkdiv_cpu0[i][6] << S5P_CLKDIV_CPU0_APLL_SHIFT));
+
+                exynos4_clkdiv_table[i].clkdiv = tmp;
+        }
+
         return cpufreq_register_driver(&exynos4_driver);
 
 out: