aboutsummaryrefslogtreecommitdiffstats
path: root/arch/blackfin/mach-common/cpufreq.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/blackfin/mach-common/cpufreq.c')
-rw-r--r--arch/blackfin/mach-common/cpufreq.c168
1 files changed, 105 insertions, 63 deletions
diff --git a/arch/blackfin/mach-common/cpufreq.c b/arch/blackfin/mach-common/cpufreq.c
index 777582897253..4391d03dc845 100644
--- a/arch/blackfin/mach-common/cpufreq.c
+++ b/arch/blackfin/mach-common/cpufreq.c
@@ -11,10 +11,13 @@
11#include <linux/init.h> 11#include <linux/init.h>
12#include <linux/cpufreq.h> 12#include <linux/cpufreq.h>
13#include <linux/fs.h> 13#include <linux/fs.h>
14#include <linux/delay.h>
14#include <asm/blackfin.h> 15#include <asm/blackfin.h>
15#include <asm/time.h> 16#include <asm/time.h>
16#include <asm/dpmc.h> 17#include <asm/dpmc.h>
17 18
19#define CPUFREQ_CPU 0
20
18/* this is the table of CCLK frequencies, in Hz */ 21/* this is the table of CCLK frequencies, in Hz */
19/* .index is the entry in the auxillary dpm_state_table[] */ 22/* .index is the entry in the auxillary dpm_state_table[] */
20static struct cpufreq_frequency_table bfin_freq_table[] = { 23static struct cpufreq_frequency_table bfin_freq_table[] = {
@@ -41,64 +44,124 @@ static struct bfin_dpm_state {
41 unsigned int tscale; /* change the divider on the core timer interrupt */ 44 unsigned int tscale; /* change the divider on the core timer interrupt */
42} dpm_state_table[3]; 45} dpm_state_table[3];
43 46
47#if defined(CONFIG_CYCLES_CLOCKSOURCE)
44/* 48/*
45 normalized to maximum frequncy offset for CYCLES, 49 * normalized to maximum frequncy offset for CYCLES,
46 used in time-ts cycles clock source, but could be used 50 * used in time-ts cycles clock source, but could be used
47 somewhere also. 51 * somewhere also.
48 */ 52 */
49unsigned long long __bfin_cycles_off; 53unsigned long long __bfin_cycles_off;
50unsigned int __bfin_cycles_mod; 54unsigned int __bfin_cycles_mod;
55#endif
51 56
52/**************************************************************************/ 57/**************************************************************************/
58static void __init bfin_init_tables(unsigned long cclk, unsigned long sclk)
59{
53 60
54static unsigned int bfin_getfreq_khz(unsigned int cpu) 61 unsigned long csel, min_cclk;
62 int index;
63
64 /* Anomaly 273 seems to still exist on non-BF54x w/dcache turned on */
65#if ANOMALY_05000273 || ANOMALY_05000274 || \
66 (!defined(CONFIG_BF54x) && defined(CONFIG_BFIN_EXTMEM_DCACHEABLE))
67 min_cclk = sclk * 2;
68#else
69 min_cclk = sclk;
70#endif
71 csel = ((bfin_read_PLL_DIV() & CSEL) >> 4);
72
73 for (index = 0; (cclk >> index) >= min_cclk && csel <= 3; index++, csel++) {
74 bfin_freq_table[index].frequency = cclk >> index;
75 dpm_state_table[index].csel = csel << 4; /* Shift now into PLL_DIV bitpos */
76 dpm_state_table[index].tscale = (TIME_SCALE / (1 << csel)) - 1;
77
78 pr_debug("cpufreq: freq:%d csel:0x%x tscale:%d\n",
79 bfin_freq_table[index].frequency,
80 dpm_state_table[index].csel,
81 dpm_state_table[index].tscale);
82 }
83 return;
84}
85
86static void bfin_adjust_core_timer(void *info)
55{ 87{
56 /* The driver only support single cpu */ 88 unsigned int tscale;
57 if (cpu != 0) 89 unsigned int index = *(unsigned int *)info;
58 return -1;
59 90
60 return get_cclk() / 1000; 91 /* we have to adjust the core timer, because it is using cclk */
92 tscale = dpm_state_table[index].tscale;
93 bfin_write_TSCALE(tscale);
94 return;
61} 95}
62 96
97static unsigned int bfin_getfreq_khz(unsigned int cpu)
98{
99 /* Both CoreA/B have the same core clock */
100 return get_cclk() / 1000;
101}
63 102
64static int bfin_target(struct cpufreq_policy *policy, 103static int bfin_target(struct cpufreq_policy *poli,
65 unsigned int target_freq, unsigned int relation) 104 unsigned int target_freq, unsigned int relation)
66{ 105{
67 unsigned int index, plldiv, tscale; 106 unsigned int index, plldiv, cpu;
68 unsigned long flags, cclk_hz; 107 unsigned long flags, cclk_hz;
69 struct cpufreq_freqs freqs; 108 struct cpufreq_freqs freqs;
109 static unsigned long lpj_ref;
110 static unsigned int lpj_ref_freq;
111
112#if defined(CONFIG_CYCLES_CLOCKSOURCE)
70 cycles_t cycles; 113 cycles_t cycles;
114#endif
71 115
72 if (cpufreq_frequency_table_target(policy, bfin_freq_table, 116 for_each_online_cpu(cpu) {
73 target_freq, relation, &index)) 117 struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
74 return -EINVAL; 118
75 119 if (!policy)
76 cclk_hz = bfin_freq_table[index].frequency; 120 continue;
77 121
78 freqs.old = bfin_getfreq_khz(0); 122 if (cpufreq_frequency_table_target(policy, bfin_freq_table,
79 freqs.new = cclk_hz; 123 target_freq, relation, &index))
80 freqs.cpu = 0; 124 return -EINVAL;
81 125
82 pr_debug("cpufreq: changing cclk to %lu; target = %u, oldfreq = %u\n", 126 cclk_hz = bfin_freq_table[index].frequency;
83 cclk_hz, target_freq, freqs.old); 127
84 128 freqs.old = bfin_getfreq_khz(0);
85 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); 129 freqs.new = cclk_hz;
86 local_irq_save_hw(flags); 130 freqs.cpu = cpu;
87 plldiv = (bfin_read_PLL_DIV() & SSEL) | dpm_state_table[index].csel; 131
88 tscale = dpm_state_table[index].tscale; 132 pr_debug("cpufreq: changing cclk to %lu; target = %u, oldfreq = %u\n",
89 bfin_write_PLL_DIV(plldiv); 133 cclk_hz, target_freq, freqs.old);
90 /* we have to adjust the core timer, because it is using cclk */ 134
91 bfin_write_TSCALE(tscale); 135 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
92 cycles = get_cycles(); 136 if (cpu == CPUFREQ_CPU) {
93 SSYNC(); 137 local_irq_save_hw(flags);
94 cycles += 10; /* ~10 cycles we lose after get_cycles() */ 138 plldiv = (bfin_read_PLL_DIV() & SSEL) |
95 __bfin_cycles_off += (cycles << __bfin_cycles_mod) - (cycles << index); 139 dpm_state_table[index].csel;
96 __bfin_cycles_mod = index; 140 bfin_write_PLL_DIV(plldiv);
97 local_irq_restore_hw(flags); 141 on_each_cpu(bfin_adjust_core_timer, &index, 1);
98 /* TODO: just test case for cycles clock source, remove later */ 142#if defined(CONFIG_CYCLES_CLOCKSOURCE)
99 pr_debug("cpufreq: done\n"); 143 cycles = get_cycles();
100 cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); 144 SSYNC();
145 cycles += 10; /* ~10 cycles we lose after get_cycles() */
146 __bfin_cycles_off +=
147 (cycles << __bfin_cycles_mod) - (cycles << index);
148 __bfin_cycles_mod = index;
149#endif
150 if (!lpj_ref_freq) {
151 lpj_ref = loops_per_jiffy;
152 lpj_ref_freq = freqs.old;
153 }
154 if (freqs.new != freqs.old) {
155 loops_per_jiffy = cpufreq_scale(lpj_ref,
156 lpj_ref_freq, freqs.new);
157 }
158 local_irq_restore_hw(flags);
159 }
160 /* TODO: just test case for cycles clock source, remove later */
161 cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
162 }
101 163
164 pr_debug("cpufreq: done\n");
102 return 0; 165 return 0;
103} 166}
104 167
@@ -110,37 +173,16 @@ static int bfin_verify_speed(struct cpufreq_policy *policy)
110static int __init __bfin_cpu_init(struct cpufreq_policy *policy) 173static int __init __bfin_cpu_init(struct cpufreq_policy *policy)
111{ 174{
112 175
113 unsigned long cclk, sclk, csel, min_cclk; 176 unsigned long cclk, sclk;
114 int index;
115
116 if (policy->cpu != 0)
117 return -EINVAL;
118 177
119 cclk = get_cclk() / 1000; 178 cclk = get_cclk() / 1000;
120 sclk = get_sclk() / 1000; 179 sclk = get_sclk() / 1000;
121 180
122#if ANOMALY_05000273 || ANOMALY_05000274 || \ 181 if (policy->cpu == CPUFREQ_CPU)
123 (!defined(CONFIG_BF54x) && defined(CONFIG_BFIN_EXTMEM_DCACHEABLE)) 182 bfin_init_tables(cclk, sclk);
124 min_cclk = sclk * 2;
125#else
126 min_cclk = sclk;
127#endif
128 csel = ((bfin_read_PLL_DIV() & CSEL) >> 4);
129
130 for (index = 0; (cclk >> index) >= min_cclk && csel <= 3; index++, csel++) {
131 bfin_freq_table[index].frequency = cclk >> index;
132 dpm_state_table[index].csel = csel << 4; /* Shift now into PLL_DIV bitpos */
133 dpm_state_table[index].tscale = (TIME_SCALE / (1 << csel)) - 1;
134
135 pr_debug("cpufreq: freq:%d csel:0x%x tscale:%d\n",
136 bfin_freq_table[index].frequency,
137 dpm_state_table[index].csel,
138 dpm_state_table[index].tscale);
139 }
140 183
141 policy->cpuinfo.transition_latency = 50000; /* 50us assumed */ 184 policy->cpuinfo.transition_latency = 50000; /* 50us assumed */
142 185
143 /*Now ,only support one cpu */
144 policy->cur = cclk; 186 policy->cur = cclk;
145 cpufreq_frequency_table_get_attr(bfin_freq_table, policy->cpu); 187 cpufreq_frequency_table_get_attr(bfin_freq_table, policy->cpu);
146 return cpufreq_frequency_table_cpuinfo(policy, bfin_freq_table); 188 return cpufreq_frequency_table_cpuinfo(policy, bfin_freq_table);