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-rw-r--r--arch/mips/au1000/common/time.c78
1 files changed, 35 insertions, 43 deletions
diff --git a/arch/mips/au1000/common/time.c b/arch/mips/au1000/common/time.c
index bdb6d73b26fb..563d9390a872 100644
--- a/arch/mips/au1000/common/time.c
+++ b/arch/mips/au1000/common/time.c
@@ -25,11 +25,9 @@
25 * 25 *
26 * Setting up the clock on the MIPS boards. 26 * Setting up the clock on the MIPS boards.
27 * 27 *
28 * Update. Always configure the kernel with CONFIG_NEW_TIME_C. This 28 * We provide the clock interrupt processing and the timer offset compute
29 * will use the user interface gettimeofday() functions from the 29 * functions. If CONFIG_PM is selected, we also ensure the 32KHz timer is
30 * arch/mips/kernel/time.c, and we provide the clock interrupt processing 30 * available. -- Dan
31 * and the timer offset compute functions. If CONFIG_PM is selected,
32 * we also ensure the 32KHz timer is available. -- Dan
33 */ 31 */
34 32
35#include <linux/types.h> 33#include <linux/types.h>
@@ -47,8 +45,7 @@ extern int allow_au1k_wait; /* default off for CP0 Counter */
47#if HZ < 100 || HZ > 1000 45#if HZ < 100 || HZ > 1000
48#error "unsupported HZ value! Must be in [100,1000]" 46#error "unsupported HZ value! Must be in [100,1000]"
49#endif 47#endif
50#define MATCH20_INC (328*100/HZ) /* magic number 328 is for HZ=100... */ 48#define MATCH20_INC (328 * 100 / HZ) /* magic number 328 is for HZ=100... */
51extern void startup_match20_interrupt(irq_handler_t handler);
52static unsigned long last_pc0, last_match20; 49static unsigned long last_pc0, last_match20;
53#endif 50#endif
54 51
@@ -61,7 +58,7 @@ static irqreturn_t counter0_irq(int irq, void *dev_id)
61{ 58{
62 unsigned long pc0; 59 unsigned long pc0;
63 int time_elapsed; 60 int time_elapsed;
64 static int jiffie_drift = 0; 61 static int jiffie_drift;
65 62
66 if (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_M20) { 63 if (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_M20) {
67 /* should never happen! */ 64 /* should never happen! */
@@ -70,13 +67,11 @@ static irqreturn_t counter0_irq(int irq, void *dev_id)
70 } 67 }
71 68
72 pc0 = au_readl(SYS_TOYREAD); 69 pc0 = au_readl(SYS_TOYREAD);
73 if (pc0 < last_match20) { 70 if (pc0 < last_match20)
74 /* counter overflowed */ 71 /* counter overflowed */
75 time_elapsed = (0xffffffff - last_match20) + pc0; 72 time_elapsed = (0xffffffff - last_match20) + pc0;
76 } 73 else
77 else {
78 time_elapsed = pc0 - last_match20; 74 time_elapsed = pc0 - last_match20;
79 }
80 75
81 while (time_elapsed > 0) { 76 while (time_elapsed > 0) {
82 do_timer(1); 77 do_timer(1);
@@ -92,8 +87,9 @@ static irqreturn_t counter0_irq(int irq, void *dev_id)
92 au_writel(last_match20 + MATCH20_INC, SYS_TOYMATCH2); 87 au_writel(last_match20 + MATCH20_INC, SYS_TOYMATCH2);
93 au_sync(); 88 au_sync();
94 89
95 /* our counter ticks at 10.009765625 ms/tick, we we're running 90 /*
96 * almost 10uS too slow per tick. 91 * Our counter ticks at 10.009765625 ms/tick, we we're running
92 * almost 10 uS too slow per tick.
97 */ 93 */
98 94
99 if (jiffie_drift >= 999) { 95 if (jiffie_drift >= 999) {
@@ -117,20 +113,17 @@ struct irqaction counter0_action = {
117/* When we wakeup from sleep, we have to "catch up" on all of the 113/* When we wakeup from sleep, we have to "catch up" on all of the
118 * timer ticks we have missed. 114 * timer ticks we have missed.
119 */ 115 */
120void 116void wakeup_counter0_adjust(void)
121wakeup_counter0_adjust(void)
122{ 117{
123 unsigned long pc0; 118 unsigned long pc0;
124 int time_elapsed; 119 int time_elapsed;
125 120
126 pc0 = au_readl(SYS_TOYREAD); 121 pc0 = au_readl(SYS_TOYREAD);
127 if (pc0 < last_match20) { 122 if (pc0 < last_match20)
128 /* counter overflowed */ 123 /* counter overflowed */
129 time_elapsed = (0xffffffff - last_match20) + pc0; 124 time_elapsed = (0xffffffff - last_match20) + pc0;
130 } 125 else
131 else {
132 time_elapsed = pc0 - last_match20; 126 time_elapsed = pc0 - last_match20;
133 }
134 127
135 while (time_elapsed > 0) { 128 while (time_elapsed > 0) {
136 time_elapsed -= MATCH20_INC; 129 time_elapsed -= MATCH20_INC;
@@ -143,10 +136,8 @@ wakeup_counter0_adjust(void)
143 136
144} 137}
145 138
146/* This is just for debugging to set the timer for a sleep delay. 139/* This is just for debugging to set the timer for a sleep delay. */
147*/ 140void wakeup_counter0_set(int ticks)
148void
149wakeup_counter0_set(int ticks)
150{ 141{
151 unsigned long pc0; 142 unsigned long pc0;
152 143
@@ -157,21 +148,22 @@ wakeup_counter0_set(int ticks)
157} 148}
158#endif 149#endif
159 150
160/* I haven't found anyone that doesn't use a 12 MHz source clock, 151/*
152 * I haven't found anyone that doesn't use a 12 MHz source clock,
161 * but just in case..... 153 * but just in case.....
162 */ 154 */
163#define AU1000_SRC_CLK 12000000 155#define AU1000_SRC_CLK 12000000
164 156
165/* 157/*
166 * We read the real processor speed from the PLL. This is important 158 * We read the real processor speed from the PLL. This is important
167 * because it is more accurate than computing it from the 32KHz 159 * because it is more accurate than computing it from the 32 KHz
168 * counter, if it exists. If we don't have an accurate processor 160 * counter, if it exists. If we don't have an accurate processor
169 * speed, all of the peripherals that derive their clocks based on 161 * speed, all of the peripherals that derive their clocks based on
170 * this advertised speed will introduce error and sometimes not work 162 * this advertised speed will introduce error and sometimes not work
171 * properly. This function is futher convoluted to still allow configurations 163 * properly. This function is futher convoluted to still allow configurations
172 * to do that in case they have really, really old silicon with a 164 * to do that in case they have really, really old silicon with a
173 * write-only PLL register, that we need the 32KHz when power management 165 * write-only PLL register, that we need the 32 KHz when power management
174 * "wait" is enabled, and we need to detect if the 32KHz isn't present 166 * "wait" is enabled, and we need to detect if the 32 KHz isn't present
175 * but requested......got it? :-) -- Dan 167 * but requested......got it? :-) -- Dan
176 */ 168 */
177unsigned long calc_clock(void) 169unsigned long calc_clock(void)
@@ -182,8 +174,7 @@ unsigned long calc_clock(void)
182 174
183 spin_lock_irqsave(&time_lock, flags); 175 spin_lock_irqsave(&time_lock, flags);
184 176
185 /* Power management cares if we don't have a 32KHz counter. 177 /* Power management cares if we don't have a 32 KHz counter. */
186 */
187 no_au1xxx_32khz = 0; 178 no_au1xxx_32khz = 0;
188 counter = au_readl(SYS_COUNTER_CNTRL); 179 counter = au_readl(SYS_COUNTER_CNTRL);
189 if (counter & SYS_CNTRL_E0) { 180 if (counter & SYS_CNTRL_E0) {
@@ -193,7 +184,7 @@ unsigned long calc_clock(void)
193 184
194 while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_T1S); 185 while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_T1S);
195 /* RTC now ticks at 32.768/16 kHz */ 186 /* RTC now ticks at 32.768/16 kHz */
196 au_writel(trim_divide-1, SYS_RTCTRIM); 187 au_writel(trim_divide - 1, SYS_RTCTRIM);
197 while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_T1S); 188 while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_T1S);
198 189
199 while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_C1S); 190 while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_C1S);
@@ -215,9 +206,11 @@ unsigned long calc_clock(void)
215#endif 206#endif
216 else 207 else
217 cpu_speed = (au_readl(SYS_CPUPLL) & 0x0000003f) * AU1000_SRC_CLK; 208 cpu_speed = (au_readl(SYS_CPUPLL) & 0x0000003f) * AU1000_SRC_CLK;
209 /* On Alchemy CPU:counter ratio is 1:1 */
218 mips_hpt_frequency = cpu_speed; 210 mips_hpt_frequency = cpu_speed;
219 // Equation: Baudrate = CPU / (SD * 2 * CLKDIV * 16) 211 /* Equation: Baudrate = CPU / (SD * 2 * CLKDIV * 16) */
220 set_au1x00_uart_baud_base(cpu_speed / (2 * ((int)(au_readl(SYS_POWERCTRL)&0x03) + 2) * 16)); 212 set_au1x00_uart_baud_base(cpu_speed / (2 * ((int)(au_readl(SYS_POWERCTRL)
213 & 0x03) + 2) * 16));
221 spin_unlock_irqrestore(&time_lock, flags); 214 spin_unlock_irqrestore(&time_lock, flags);
222 return cpu_speed; 215 return cpu_speed;
223} 216}
@@ -228,10 +221,10 @@ void __init plat_time_init(void)
228 221
229 est_freq += 5000; /* round */ 222 est_freq += 5000; /* round */
230 est_freq -= est_freq%10000; 223 est_freq -= est_freq%10000;
231 printk("CPU frequency %d.%02d MHz\n", est_freq/1000000, 224 printk(KERN_INFO "CPU frequency %u.%02u MHz\n",
232 (est_freq%1000000)*100/1000000); 225 est_freq / 1000000, ((est_freq % 1000000) * 100) / 1000000);
233 set_au1x00_speed(est_freq); 226 set_au1x00_speed(est_freq);
234 set_au1x00_lcd_clock(); // program the LCD clock 227 set_au1x00_lcd_clock(); /* program the LCD clock */
235 228
236#ifdef CONFIG_PM 229#ifdef CONFIG_PM
237 /* 230 /*
@@ -243,30 +236,29 @@ void __init plat_time_init(void)
243 * counter 0 interrupt as a special irq and it doesn't show 236 * counter 0 interrupt as a special irq and it doesn't show
244 * up under /proc/interrupts. 237 * up under /proc/interrupts.
245 * 238 *
246 * Check to ensure we really have a 32KHz oscillator before 239 * Check to ensure we really have a 32 KHz oscillator before
247 * we do this. 240 * we do this.
248 */ 241 */
249 if (no_au1xxx_32khz) 242 if (no_au1xxx_32khz)
250 printk("WARNING: no 32KHz clock found.\n"); 243 printk(KERN_WARNING "WARNING: no 32KHz clock found.\n");
251 else { 244 else {
252 while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_C0S); 245 while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_C0S);
253 au_writel(0, SYS_TOYWRITE); 246 au_writel(0, SYS_TOYWRITE);
254 while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_C0S); 247 while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_C0S);
255 248
256 au_writel(au_readl(SYS_WAKEMSK) | (1<<8), SYS_WAKEMSK); 249 au_writel(au_readl(SYS_WAKEMSK) | (1 << 8), SYS_WAKEMSK);
257 au_writel(~0, SYS_WAKESRC); 250 au_writel(~0, SYS_WAKESRC);
258 au_sync(); 251 au_sync();
259 while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_M20); 252 while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_M20);
260 253
261 /* setup match20 to interrupt once every HZ */ 254 /* Setup match20 to interrupt once every HZ */
262 last_pc0 = last_match20 = au_readl(SYS_TOYREAD); 255 last_pc0 = last_match20 = au_readl(SYS_TOYREAD);
263 au_writel(last_match20 + MATCH20_INC, SYS_TOYMATCH2); 256 au_writel(last_match20 + MATCH20_INC, SYS_TOYMATCH2);
264 au_sync(); 257 au_sync();
265 while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_M20); 258 while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_M20);
266 setup_irq(AU1000_TOY_MATCH2_INT, &counter0_action); 259 setup_irq(AU1000_TOY_MATCH2_INT, &counter0_action);
267 260
268 /* We can use the real 'wait' instruction. 261 /* We can use the real 'wait' instruction. */
269 */
270 allow_au1k_wait = 1; 262 allow_au1k_wait = 1;
271 } 263 }
272 264