| 1 | |
| 2 | |
| 3 | *
|
| 4 | * Copyright (c) 2011 Samsung Electronics Co., Ltd.
|
| 5 | * http://www.samsung.com
|
| 6 | *
|
| 7 | * Exynos4 MCT(Multi-Core Timer) support
|
| 8 |
|
| 9 |
|
| 10 | #include <linux/interrupt.h>
|
| 11 | #include <linux/irq.h>
|
| 12 | #include <linux/err.h>
|
| 13 | #include <linux/clk.h>
|
| 14 | #include <linux/clockchips.h>
|
| 15 | #include <linux/cpu.h>
|
| 16 | #include <linux/delay.h>
|
| 17 | #include <linux/percpu.h>
|
| 18 | #include <linux/of.h>
|
| 19 | #include <linux/of_irq.h>
|
| 20 | #include <linux/of_address.h>
|
| 21 | #include <linux/clocksource.h>
|
| 22 | #include <linux/sched_clock.h>
|
| 23 |
|
| 24 | #define EXYNOS4_MCTREG(x) (x)
|
| 25 | #define EXYNOS4_MCT_G_CNT_L EXYNOS4_MCTREG(0x100)
|
| 26 | #define EXYNOS4_MCT_G_CNT_U EXYNOS4_MCTREG(0x104)
|
| 27 | #define EXYNOS4_MCT_G_CNT_WSTAT EXYNOS4_MCTREG(0x110)
|
| 28 | #define EXYNOS4_MCT_G_COMP0_L EXYNOS4_MCTREG(0x200)
|
| 29 | #define EXYNOS4_MCT_G_COMP0_U EXYNOS4_MCTREG(0x204)
|
| 30 | #define EXYNOS4_MCT_G_COMP0_ADD_INCR EXYNOS4_MCTREG(0x208)
|
| 31 | #define EXYNOS4_MCT_G_TCON EXYNOS4_MCTREG(0x240)
|
| 32 | #define EXYNOS4_MCT_G_INT_CSTAT EXYNOS4_MCTREG(0x244)
|
| 33 | #define EXYNOS4_MCT_G_INT_ENB EXYNOS4_MCTREG(0x248)
|
| 34 | #define EXYNOS4_MCT_G_WSTAT EXYNOS4_MCTREG(0x24C)
|
| 35 | #define _EXYNOS4_MCT_L_BASE EXYNOS4_MCTREG(0x300)
|
| 36 | #define EXYNOS4_MCT_L_BASE(x) (_EXYNOS4_MCT_L_BASE + (0x100 * (x)))
|
| 37 | #define EXYNOS4_MCT_L_MASK (0xffffff00)
|
| 38 |
|
| 39 | #define MCT_L_TCNTB_OFFSET (0x00)
|
| 40 | #define MCT_L_ICNTB_OFFSET (0x08)
|
| 41 | #define MCT_L_TCON_OFFSET (0x20)
|
| 42 | #define MCT_L_INT_CSTAT_OFFSET (0x30)
|
| 43 | #define MCT_L_INT_ENB_OFFSET (0x34)
|
| 44 | #define MCT_L_WSTAT_OFFSET (0x40)
|
| 45 | #define MCT_G_TCON_START (1 << 8)
|
| 46 | #define MCT_G_TCON_COMP0_AUTO_INC (1 << 1)
|
| 47 | #define MCT_G_TCON_COMP0_ENABLE (1 << 0)
|
| 48 | #define MCT_L_TCON_INTERVAL_MODE (1 << 2)
|
| 49 | #define MCT_L_TCON_INT_START (1 << 1)
|
| 50 | #define MCT_L_TCON_TIMER_START (1 << 0)
|
| 51 |
|
| 52 | #define TICK_BASE_CNT 1
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| 53 |
|
| 54 | #ifdef CONFIG_ARM
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| 55 |
|
| 56 | #define MCT_CLKSOURCE_RATING 450
|
| 57 | #define MCT_CLKEVENTS_RATING 500
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| 58 | #else
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| 59 | #define MCT_CLKSOURCE_RATING 350
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| 60 | #define MCT_CLKEVENTS_RATING 350
|
| 61 | #endif
|
| 62 |
|
| 63 |
|
| 64 | #define MCT_G0_IRQ 0
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| 65 |
|
| 66 | #define MCT_L0_IRQ 4
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| 67 |
|
| 68 | #define MCT_NR_IRQS 20
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| 69 |
|
| 70 | #define MCT_NR_LOCAL (MCT_NR_IRQS - MCT_L0_IRQ)
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| 71 |
|
| 72 | enum {
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| 73 | MCT_INT_SPI,
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| 74 | MCT_INT_PPI
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| 75 | };
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| 76 |
|
| 77 | static void __iomem *reg_base;
|
| 78 | static unsigned long clk_rate;
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| 79 | static unsigned int mct_int_type;
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| 80 | static int mct_irqs[MCT_NR_IRQS];
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| 81 |
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| 82 | struct mct_clock_event_device {
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| 83 | struct clock_event_device evt;
|
| 84 | unsigned long base;
|
| 85 | |
| 86 | * The length of the name must be adjusted if number of
|
| 87 | * local timer interrupts grow over two digits
|
| 88 |
|
| 89 | char name[11];
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| 90 | };
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| 91 |
|
| 92 | static void exynos4_mct_write(unsigned int value, unsigned long offset)
|
| 93 | {
|
| 94 | unsigned long stat_addr;
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| 95 | u32 mask;
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| 96 | u32 i;
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| 97 |
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| 98 | writel_relaxed(value, reg_base + offset);
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| 99 |
|
| 100 | if (likely(offset >= EXYNOS4_MCT_L_BASE(0))) {
|
| 101 | stat_addr = (offset & EXYNOS4_MCT_L_MASK) + MCT_L_WSTAT_OFFSET;
|
| 102 | switch (offset & ~EXYNOS4_MCT_L_MASK) {
|
| 103 | case MCT_L_TCON_OFFSET:
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| 104 | mask = 1 << 3;
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| 105 | break;
|
| 106 | case MCT_L_ICNTB_OFFSET:
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| 107 | mask = 1 << 1;
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| 108 | break;
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| 109 | case MCT_L_TCNTB_OFFSET:
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| 110 | mask = 1 << 0;
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| 111 | break;
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| 112 | default:
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| 113 | return;
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| 114 | }
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| 115 | } else {
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| 116 | switch (offset) {
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| 117 | case EXYNOS4_MCT_G_TCON:
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| 118 | stat_addr = EXYNOS4_MCT_G_WSTAT;
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| 119 | mask = 1 << 16;
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| 120 | break;
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| 121 | case EXYNOS4_MCT_G_COMP0_L:
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| 122 | stat_addr = EXYNOS4_MCT_G_WSTAT;
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| 123 | mask = 1 << 0;
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| 124 | break;
|
| 125 | case EXYNOS4_MCT_G_COMP0_U:
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| 126 | stat_addr = EXYNOS4_MCT_G_WSTAT;
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| 127 | mask = 1 << 1;
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| 128 | break;
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| 129 | case EXYNOS4_MCT_G_COMP0_ADD_INCR:
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| 130 | stat_addr = EXYNOS4_MCT_G_WSTAT;
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| 131 | mask = 1 << 2;
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| 132 | break;
|
| 133 | case EXYNOS4_MCT_G_CNT_L:
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| 134 | stat_addr = EXYNOS4_MCT_G_CNT_WSTAT;
|
| 135 | mask = 1 << 0;
|
| 136 | break;
|
| 137 | case EXYNOS4_MCT_G_CNT_U:
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| 138 | stat_addr = EXYNOS4_MCT_G_CNT_WSTAT;
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| 139 | mask = 1 << 1;
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| 140 | break;
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| 141 | default:
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| 142 | return;
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| 143 | }
|
| 144 | }
|
| 145 |
|
| 146 |
|
| 147 | for (i = 0; i < loops_per_jiffy / 1000 * HZ; i++)
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| 148 | if (readl_relaxed(reg_base + stat_addr) & mask) {
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| 149 | writel_relaxed(mask, reg_base + stat_addr);
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| 150 | return;
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| 151 | }
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| 152 |
|
| 153 | panic("MCT hangs after writing %d (offset:0x%lx)\n", value, offset);
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| 154 | }
|
| 155 |
|
| 156 |
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| 157 | static void exynos4_mct_frc_start(void)
|
| 158 | {
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| 159 | u32 reg;
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| 160 |
|
| 161 | reg = readl_relaxed(reg_base + EXYNOS4_MCT_G_TCON);
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| 162 | reg |= MCT_G_TCON_START;
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| 163 | exynos4_mct_write(reg, EXYNOS4_MCT_G_TCON);
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| 164 | }
|
| 165 |
|
| 166 | |
| 167 | * exynos4_read_count_64 - Read all 64-bits of the global counter
|
| 168 | *
|
| 169 | * This will read all 64-bits of the global counter taking care to make sure
|
| 170 | * that the upper and lower half match. Note that reading the MCT can be quite
|
| 171 | * slow (hundreds of nanoseconds) so you should use the 32-bit (lower half
|
| 172 | * only) version when possible.
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| 173 | *
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| 174 | * Returns the number of cycles in the global counter.
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| 175 |
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| 176 | static u64 exynos4_read_count_64(void)
|
| 177 | {
|
| 178 | unsigned int lo, hi;
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| 179 | u32 hi2 = readl_relaxed(reg_base + EXYNOS4_MCT_G_CNT_U);
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| 180 |
|
| 181 | do {
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| 182 | hi = hi2;
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| 183 | lo = readl_relaxed(reg_base + EXYNOS4_MCT_G_CNT_L);
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| 184 | hi2 = readl_relaxed(reg_base + EXYNOS4_MCT_G_CNT_U);
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| 185 | } while (hi != hi2);
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| 186 |
|
| 187 | return ((u64)hi << 32) | lo;
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| 188 | }
|
| 189 |
|
| 190 | |
| 191 | * exynos4_read_count_32 - Read the lower 32-bits of the global counter
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| 192 | *
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| 193 | * This will read just the lower 32-bits of the global counter. This is marked
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| 194 | * as notrace so it can be used by the scheduler clock.
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| 195 | *
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| 196 | * Returns the number of cycles in the global counter (lower 32 bits).
|
| 197 |
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| 198 | static u32 notrace exynos4_read_count_32(void)
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| 199 | {
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| 200 | return readl_relaxed(reg_base + EXYNOS4_MCT_G_CNT_L);
|
| 201 | }
|
| 202 |
|
| 203 | static u64 exynos4_frc_read(struct clocksource *cs)
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| 204 | {
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| 205 | return exynos4_read_count_32();
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| 206 | }
|
| 207 |
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| 208 | static void exynos4_frc_resume(struct clocksource *cs)
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| 209 | {
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| 210 | exynos4_mct_frc_start();
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| 211 | }
|
| 212 |
|
| 213 | static struct clocksource mct_frc = {
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| 214 | .name = "mct-frc",
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| 215 | .rating = MCT_CLKSOURCE_RATING,
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| 216 | .read = exynos4_frc_read,
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| 217 | .mask = CLOCKSOURCE_MASK(32),
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| 218 | .flags = CLOCK_SOURCE_IS_CONTINUOUS,
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| 219 | .resume = exynos4_frc_resume,
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| 220 | };
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| 221 |
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| 222 | static u64 notrace exynos4_read_sched_clock(void)
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| 223 | {
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| 224 | return exynos4_read_count_32();
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| 225 | }
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| 226 |
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| 227 | #if defined(CONFIG_ARM)
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| 228 | static struct delay_timer exynos4_delay_timer;
|
| 229 |
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| 230 | static cycles_t exynos4_read_current_timer(void)
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| 231 | {
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| 232 | BUILD_BUG_ON_MSG(sizeof(cycles_t) != sizeof(u32),
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| 233 | "cycles_t needs to move to 32-bit for ARM64 usage");
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| 234 | return exynos4_read_count_32();
|
| 235 | }
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| 236 | #endif
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| 237 |
|
| 238 | static int __init exynos4_clocksource_init(bool frc_shared)
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| 239 | {
|
| 240 | |
| 241 | * When the frc is shared, the main processor should have already
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| 242 | * turned it on and we shouldn't be writing to TCON.
|
| 243 |
|
| 244 | if (frc_shared)
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| 245 | mct_frc.resume = NULL;
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| 246 | else
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| 247 | exynos4_mct_frc_start();
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| 248 |
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| 249 | #if defined(CONFIG_ARM)
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| 250 | exynos4_delay_timer.read_current_timer = &exynos4_read_current_timer;
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| 251 | exynos4_delay_timer.freq = clk_rate;
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| 252 | register_current_timer_delay(&exynos4_delay_timer);
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| 253 | #endif
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| 254 |
|
| 255 | if (clocksource_register_hz(&mct_frc, clk_rate))
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| 256 | panic("%s: can't register clocksource\n", mct_frc.name);
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| 257 |
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| 258 | sched_clock_register(exynos4_read_sched_clock, 32, clk_rate);
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| 259 |
|
| 260 | return 0;
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| 261 | }
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| 262 |
|
| 263 | static void exynos4_mct_comp0_stop(void)
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| 264 | {
|
| 265 | unsigned int tcon;
|
| 266 |
|
| 267 | tcon = readl_relaxed(reg_base + EXYNOS4_MCT_G_TCON);
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| 268 | tcon &= ~(MCT_G_TCON_COMP0_ENABLE | MCT_G_TCON_COMP0_AUTO_INC);
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| 269 |
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| 270 | exynos4_mct_write(tcon, EXYNOS4_MCT_G_TCON);
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| 271 | exynos4_mct_write(0, EXYNOS4_MCT_G_INT_ENB);
|
| 272 | }
|
| 273 |
|
| 274 | static void exynos4_mct_comp0_start(bool periodic, unsigned long cycles)
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| 275 | {
|
| 276 | unsigned int tcon;
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| 277 | u64 comp_cycle;
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| 278 |
|
| 279 | tcon = readl_relaxed(reg_base + EXYNOS4_MCT_G_TCON);
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| 280 |
|
| 281 | if (periodic) {
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| 282 | tcon |= MCT_G_TCON_COMP0_AUTO_INC;
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| 283 | exynos4_mct_write(cycles, EXYNOS4_MCT_G_COMP0_ADD_INCR);
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| 284 | }
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| 285 |
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| 286 | comp_cycle = exynos4_read_count_64() + cycles;
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| 287 | exynos4_mct_write((u32)comp_cycle, EXYNOS4_MCT_G_COMP0_L);
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| 288 | exynos4_mct_write((u32)(comp_cycle >> 32), EXYNOS4_MCT_G_COMP0_U);
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| 289 |
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| 290 | exynos4_mct_write(0x1, EXYNOS4_MCT_G_INT_ENB);
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| 291 |
|
| 292 | tcon |= MCT_G_TCON_COMP0_ENABLE;
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| 293 | exynos4_mct_write(tcon , EXYNOS4_MCT_G_TCON);
|
| 294 | }
|
| 295 |
|
| 296 | static int exynos4_comp_set_next_event(unsigned long cycles,
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| 297 | struct clock_event_device *evt)
|
| 298 | {
|
| 299 | exynos4_mct_comp0_start(false, cycles);
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| 300 |
|
| 301 | return 0;
|
| 302 | }
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| 303 |
|
| 304 | static int mct_set_state_shutdown(struct clock_event_device *evt)
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| 305 | {
|
| 306 | exynos4_mct_comp0_stop();
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| 307 | return 0;
|
| 308 | }
|
| 309 |
|
| 310 | static int mct_set_state_periodic(struct clock_event_device *evt)
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| 311 | {
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| 312 | unsigned long cycles_per_jiffy;
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| 313 |
|
| 314 | cycles_per_jiffy = (((unsigned long long)NSEC_PER_SEC / HZ * evt->mult)
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| 315 | >> evt->shift);
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| 316 | exynos4_mct_comp0_stop();
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| 317 | exynos4_mct_comp0_start(true, cycles_per_jiffy);
|
| 318 | return 0;
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| 319 | }
|
| 320 |
|
| 321 | static struct clock_event_device mct_comp_device = {
|
| 322 | .name = "mct-comp",
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| 323 | .features = CLOCK_EVT_FEAT_PERIODIC |
|
| 324 | CLOCK_EVT_FEAT_ONESHOT,
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| 325 | .rating = 250,
|
| 326 | .set_next_event = exynos4_comp_set_next_event,
|
| 327 | .set_state_periodic = mct_set_state_periodic,
|
| 328 | .set_state_shutdown = mct_set_state_shutdown,
|
| 329 | .set_state_oneshot = mct_set_state_shutdown,
|
| 330 | .set_state_oneshot_stopped = mct_set_state_shutdown,
|
| 331 | .tick_resume = mct_set_state_shutdown,
|
| 332 | };
|
| 333 |
|
| 334 | static irqreturn_t exynos4_mct_comp_isr(int irq, void *dev_id)
|
| 335 | {
|
| 336 | struct clock_event_device *evt = dev_id;
|
| 337 |
|
| 338 | exynos4_mct_write(0x1, EXYNOS4_MCT_G_INT_CSTAT);
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| 339 |
|
| 340 | evt->event_handler(evt);
|
| 341 |
|
| 342 | return IRQ_HANDLED;
|
| 343 | }
|
| 344 |
|
| 345 | static int exynos4_clockevent_init(void)
|
| 346 | {
|
| 347 | mct_comp_device.cpumask = cpumask_of(0);
|
| 348 | clockevents_config_and_register(&mct_comp_device, clk_rate,
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| 349 | 0xf, 0xffffffff);
|
| 350 | if (request_irq(mct_irqs[MCT_G0_IRQ], exynos4_mct_comp_isr,
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| 351 | IRQF_TIMER | IRQF_IRQPOLL, "mct_comp_irq",
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| 352 | &mct_comp_device))
|
| 353 | pr_err("%s: request_irq() failed\n", "mct_comp_irq");
|
| 354 |
|
| 355 | return 0;
|
| 356 | }
|
| 357 |
|
| 358 | static DEFINE_PER_CPU(struct mct_clock_event_device, percpu_mct_tick);
|
| 359 |
|
| 360 |
|
| 361 | static void exynos4_mct_tick_stop(struct mct_clock_event_device *mevt)
|
| 362 | {
|
| 363 | unsigned long tmp;
|
| 364 | unsigned long mask = MCT_L_TCON_INT_START | MCT_L_TCON_TIMER_START;
|
| 365 | unsigned long offset = mevt->base + MCT_L_TCON_OFFSET;
|
| 366 |
|
| 367 | tmp = readl_relaxed(reg_base + offset);
|
| 368 | if (tmp & mask) {
|
| 369 | tmp &= ~mask;
|
| 370 | exynos4_mct_write(tmp, offset);
|
| 371 | }
|
| 372 | }
|
| 373 |
|
| 374 | static void exynos4_mct_tick_start(unsigned long cycles,
|
| 375 | struct mct_clock_event_device *mevt)
|
| 376 | {
|
| 377 | unsigned long tmp;
|
| 378 |
|
| 379 | exynos4_mct_tick_stop(mevt);
|
| 380 |
|
| 381 | tmp = (1 << 31) | cycles;
|
| 382 |
|
| 383 |
|
| 384 | exynos4_mct_write(tmp, mevt->base + MCT_L_ICNTB_OFFSET);
|
| 385 |
|
| 386 |
|
| 387 | exynos4_mct_write(0x1, mevt->base + MCT_L_INT_ENB_OFFSET);
|
| 388 |
|
| 389 | tmp = readl_relaxed(reg_base + mevt->base + MCT_L_TCON_OFFSET);
|
| 390 | tmp |= MCT_L_TCON_INT_START | MCT_L_TCON_TIMER_START |
|
| 391 | MCT_L_TCON_INTERVAL_MODE;
|
| 392 | exynos4_mct_write(tmp, mevt->base + MCT_L_TCON_OFFSET);
|
| 393 | }
|
| 394 |
|
| 395 | static void exynos4_mct_tick_clear(struct mct_clock_event_device *mevt)
|
| 396 | {
|
| 397 |
|
| 398 | if (readl_relaxed(reg_base + mevt->base + MCT_L_INT_CSTAT_OFFSET) & 1)
|
| 399 | exynos4_mct_write(0x1, mevt->base + MCT_L_INT_CSTAT_OFFSET);
|
| 400 | }
|
| 401 |
|
| 402 | static int exynos4_tick_set_next_event(unsigned long cycles,
|
| 403 | struct clock_event_device *evt)
|
| 404 | {
|
| 405 | struct mct_clock_event_device *mevt;
|
| 406 |
|
| 407 | mevt = container_of(evt, struct mct_clock_event_device, evt);
|
| 408 | exynos4_mct_tick_start(cycles, mevt);
|
| 409 | return 0;
|
| 410 | }
|
| 411 |
|
| 412 | static int set_state_shutdown(struct clock_event_device *evt)
|
| 413 | {
|
| 414 | struct mct_clock_event_device *mevt;
|
| 415 |
|
| 416 | mevt = container_of(evt, struct mct_clock_event_device, evt);
|
| 417 | exynos4_mct_tick_stop(mevt);
|
| 418 | exynos4_mct_tick_clear(mevt);
|
| 419 | return 0;
|
| 420 | }
|
| 421 |
|
| 422 | static int set_state_periodic(struct clock_event_device *evt)
|
| 423 | {
|
| 424 | struct mct_clock_event_device *mevt;
|
| 425 | unsigned long cycles_per_jiffy;
|
| 426 |
|
| 427 | mevt = container_of(evt, struct mct_clock_event_device, evt);
|
| 428 | cycles_per_jiffy = (((unsigned long long)NSEC_PER_SEC / HZ * evt->mult)
|
| 429 | >> evt->shift);
|
| 430 | exynos4_mct_tick_stop(mevt);
|
| 431 | exynos4_mct_tick_start(cycles_per_jiffy, mevt);
|
| 432 | return 0;
|
| 433 | }
|
| 434 |
|
| 435 | static irqreturn_t exynos4_mct_tick_isr(int irq, void *dev_id)
|
| 436 | {
|
| 437 | struct mct_clock_event_device *mevt = dev_id;
|
| 438 | struct clock_event_device *evt = &mevt->evt;
|
| 439 |
|
| 440 | |
| 441 | * This is for supporting oneshot mode.
|
| 442 | * Mct would generate interrupt periodically
|
| 443 | * without explicit stopping.
|
| 444 |
|
| 445 | if (!clockevent_state_periodic(&mevt->evt))
|
| 446 | exynos4_mct_tick_stop(mevt);
|
| 447 |
|
| 448 | exynos4_mct_tick_clear(mevt);
|
| 449 |
|
| 450 | evt->event_handler(evt);
|
| 451 |
|
| 452 | return IRQ_HANDLED;
|
| 453 | }
|
| 454 |
|
| 455 | static int exynos4_mct_starting_cpu(unsigned int cpu)
|
| 456 | {
|
| 457 | struct mct_clock_event_device *mevt =
|
| 458 | per_cpu_ptr(&percpu_mct_tick, cpu);
|
| 459 | struct clock_event_device *evt = &mevt->evt;
|
| 460 |
|
| 461 | snprintf(mevt->name, sizeof(mevt->name), "mct_tick%d", cpu);
|
| 462 |
|
| 463 | evt->name = mevt->name;
|
| 464 | evt->cpumask = cpumask_of(cpu);
|
| 465 | evt->set_next_event = exynos4_tick_set_next_event;
|
| 466 | evt->set_state_periodic = set_state_periodic;
|
| 467 | evt->set_state_shutdown = set_state_shutdown;
|
| 468 | evt->set_state_oneshot = set_state_shutdown;
|
| 469 | evt->set_state_oneshot_stopped = set_state_shutdown;
|
| 470 | evt->tick_resume = set_state_shutdown;
|
| 471 | evt->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT |
|
| 472 | CLOCK_EVT_FEAT_PERCPU;
|
| 473 | evt->rating = MCT_CLKEVENTS_RATING;
|
| 474 |
|
| 475 | exynos4_mct_write(TICK_BASE_CNT, mevt->base + MCT_L_TCNTB_OFFSET);
|
| 476 |
|
| 477 | if (mct_int_type == MCT_INT_SPI) {
|
| 478 |
|
| 479 | if (evt->irq == -1)
|
| 480 | return -EIO;
|
| 481 |
|
| 482 | irq_force_affinity(evt->irq, cpumask_of(cpu));
|
| 483 | enable_irq(evt->irq);
|
| 484 | } else {
|
| 485 | enable_percpu_irq(mct_irqs[MCT_L0_IRQ], 0);
|
| 486 | }
|
| 487 | clockevents_config_and_register(evt, clk_rate / (TICK_BASE_CNT + 1),
|
| 488 | 0xf, 0x7fffffff);
|
| 489 |
|
| 490 | return 0;
|
| 491 | }
|
| 492 |
|
| 493 | static int exynos4_mct_dying_cpu(unsigned int cpu)
|
| 494 | {
|
| 495 | struct mct_clock_event_device *mevt =
|
| 496 | per_cpu_ptr(&percpu_mct_tick, cpu);
|
| 497 | struct clock_event_device *evt = &mevt->evt;
|
| 498 |
|
| 499 | if (mct_int_type == MCT_INT_SPI) {
|
| 500 | if (evt->irq != -1)
|
| 501 | disable_irq_nosync(evt->irq);
|
| 502 | exynos4_mct_write(0x1, mevt->base + MCT_L_INT_CSTAT_OFFSET);
|
| 503 | } else {
|
| 504 | disable_percpu_irq(mct_irqs[MCT_L0_IRQ]);
|
| 505 | }
|
| 506 | return 0;
|
| 507 | }
|
| 508 |
|
| 509 | static int __init exynos4_timer_resources(struct device_node *np)
|
| 510 | {
|
| 511 | struct clk *mct_clk, *tick_clk;
|
| 512 |
|
| 513 | reg_base = of_iomap(np, 0);
|
| 514 | if (!reg_base)
|
| 515 | panic("%s: unable to ioremap mct address space\n", __func__);
|
| 516 |
|
| 517 | tick_clk = of_clk_get_by_name(np, "fin_pll");
|
| 518 | if (IS_ERR(tick_clk))
|
| 519 | panic("%s: unable to determine tick clock rate\n", __func__);
|
| 520 | clk_rate = clk_get_rate(tick_clk);
|
| 521 |
|
| 522 | mct_clk = of_clk_get_by_name(np, "mct");
|
| 523 | if (IS_ERR(mct_clk))
|
| 524 | panic("%s: unable to retrieve mct clock instance\n", __func__);
|
| 525 | clk_prepare_enable(mct_clk);
|
| 526 |
|
| 527 | return 0;
|
| 528 | }
|
| 529 |
|
| 530 | |
| 531 | * exynos4_timer_interrupts - initialize MCT interrupts
|
| 532 | * @np: device node for MCT
|
| 533 | * @int_type: interrupt type, MCT_INT_PPI or MCT_INT_SPI
|
| 534 | * @local_idx: array mapping CPU numbers to local timer indices
|
| 535 | * @nr_local: size of @local_idx array
|
| 536 |
|
| 537 | static int __init exynos4_timer_interrupts(struct device_node *np,
|
| 538 | unsigned int int_type,
|
| 539 | const u32 *local_idx,
|
| 540 | size_t nr_local)
|
| 541 | {
|
| 542 | int nr_irqs, i, err, cpu;
|
| 543 |
|
| 544 | mct_int_type = int_type;
|
| 545 |
|
| 546 |
|
| 547 | mct_irqs[MCT_G0_IRQ] = irq_of_parse_and_map(np, MCT_G0_IRQ);
|
| 548 |
|
| 549 | |
| 550 | * Find out the number of local irqs specified. The local
|
| 551 | * timer irqs are specified after the four global timer
|
| 552 | * irqs are specified.
|
| 553 |
|
| 554 | nr_irqs = of_irq_count(np);
|
| 555 | if (nr_irqs > ARRAY_SIZE(mct_irqs)) {
|
| 556 | pr_err("exynos-mct: too many (%d) interrupts configured in DT\n",
|
| 557 | nr_irqs);
|
| 558 | nr_irqs = ARRAY_SIZE(mct_irqs);
|
| 559 | }
|
| 560 | for (i = MCT_L0_IRQ; i < nr_irqs; i++)
|
| 561 | mct_irqs[i] = irq_of_parse_and_map(np, i);
|
| 562 |
|
| 563 | if (mct_int_type == MCT_INT_PPI) {
|
| 564 |
|
| 565 | err = request_percpu_irq(mct_irqs[MCT_L0_IRQ],
|
| 566 | exynos4_mct_tick_isr, "MCT",
|
| 567 | &percpu_mct_tick);
|
| 568 | WARN(err, "MCT: can't request IRQ %d (%d)\n",
|
| 569 | mct_irqs[MCT_L0_IRQ], err);
|
| 570 | } else {
|
| 571 | for_each_possible_cpu(cpu) {
|
| 572 | int mct_irq;
|
| 573 | unsigned int irq_idx;
|
| 574 | struct mct_clock_event_device *pcpu_mevt =
|
| 575 | per_cpu_ptr(&percpu_mct_tick, cpu);
|
| 576 |
|
| 577 | if (cpu >= nr_local) {
|
| 578 | err = -EINVAL;
|
| 579 | goto out_irq;
|
| 580 | }
|
| 581 |
|
| 582 | irq_idx = MCT_L0_IRQ + local_idx[cpu];
|
| 583 |
|
| 584 | pcpu_mevt->evt.irq = -1;
|
| 585 | if (irq_idx >= ARRAY_SIZE(mct_irqs))
|
| 586 | break;
|
| 587 | mct_irq = mct_irqs[irq_idx];
|
| 588 |
|
| 589 | irq_set_status_flags(mct_irq, IRQ_NOAUTOEN);
|
| 590 | if (request_irq(mct_irq,
|
| 591 | exynos4_mct_tick_isr,
|
| 592 | IRQF_TIMER | IRQF_NOBALANCING,
|
| 593 | pcpu_mevt->name, pcpu_mevt)) {
|
| 594 | pr_err("exynos-mct: cannot register IRQ (cpu%d)\n",
|
| 595 | cpu);
|
| 596 |
|
| 597 | continue;
|
| 598 | }
|
| 599 | pcpu_mevt->evt.irq = mct_irq;
|
| 600 | }
|
| 601 | }
|
| 602 |
|
| 603 | for_each_possible_cpu(cpu) {
|
| 604 | struct mct_clock_event_device *mevt = per_cpu_ptr(&percpu_mct_tick, cpu);
|
| 605 |
|
| 606 | if (cpu >= nr_local) {
|
| 607 | err = -EINVAL;
|
| 608 | goto out_irq;
|
| 609 | }
|
| 610 |
|
| 611 | mevt->base = EXYNOS4_MCT_L_BASE(local_idx[cpu]);
|
| 612 | }
|
| 613 |
|
| 614 |
|
| 615 | err = cpuhp_setup_state(CPUHP_AP_EXYNOS4_MCT_TIMER_STARTING,
|
| 616 | "clockevents/exynos4/mct_timer:starting",
|
| 617 | exynos4_mct_starting_cpu,
|
| 618 | exynos4_mct_dying_cpu);
|
| 619 | if (err)
|
| 620 | goto out_irq;
|
| 621 |
|
| 622 | return 0;
|
| 623 |
|
| 624 | out_irq:
|
| 625 | if (mct_int_type == MCT_INT_PPI) {
|
| 626 | free_percpu_irq(mct_irqs[MCT_L0_IRQ], &percpu_mct_tick);
|
| 627 | } else {
|
| 628 | for_each_possible_cpu(cpu) {
|
| 629 | struct mct_clock_event_device *pcpu_mevt =
|
| 630 | per_cpu_ptr(&percpu_mct_tick, cpu);
|
| 631 |
|
| 632 | if (pcpu_mevt->evt.irq != -1) {
|
| 633 | free_irq(pcpu_mevt->evt.irq, pcpu_mevt);
|
| 634 | pcpu_mevt->evt.irq = -1;
|
| 635 | }
|
| 636 | }
|
| 637 | }
|
| 638 | return err;
|
| 639 | }
|
| 640 |
|
| 641 | static int __init mct_init_dt(struct device_node *np, unsigned int int_type)
|
| 642 | {
|
| 643 | bool frc_shared = of_property_read_bool(np, "samsung,frc-shared");
|
| 644 | u32 local_idx[MCT_NR_LOCAL] = {0};
|
| 645 | int nr_local;
|
| 646 | int ret;
|
| 647 |
|
| 648 | nr_local = of_property_count_u32_elems(np, "samsung,local-timers");
|
| 649 | if (nr_local == 0)
|
| 650 | return -EINVAL;
|
| 651 | if (nr_local > 0) {
|
| 652 | if (nr_local > ARRAY_SIZE(local_idx))
|
| 653 | return -EINVAL;
|
| 654 |
|
| 655 | ret = of_property_read_u32_array(np, "samsung,local-timers",
|
| 656 | local_idx, nr_local);
|
| 657 | if (ret)
|
| 658 | return ret;
|
| 659 | } else {
|
| 660 | int i;
|
| 661 |
|
| 662 | nr_local = ARRAY_SIZE(local_idx);
|
| 663 | for (i = 0; i < nr_local; i++)
|
| 664 | local_idx[i] = i;
|
| 665 | }
|
| 666 |
|
| 667 | ret = exynos4_timer_resources(np);
|
| 668 | if (ret)
|
| 669 | return ret;
|
| 670 |
|
| 671 | ret = exynos4_timer_interrupts(np, int_type, local_idx, nr_local);
|
| 672 | if (ret)
|
| 673 | return ret;
|
| 674 |
|
| 675 | ret = exynos4_clocksource_init(frc_shared);
|
| 676 | if (ret)
|
| 677 | return ret;
|
| 678 |
|
| 679 | |
| 680 | * When the FRC is shared with a main processor, this secondary
|
| 681 | * processor cannot use the global comparator.
|
| 682 |
|
| 683 | if (frc_shared)
|
| 684 | return 0;
|
| 685 |
|
| 686 | return exynos4_clockevent_init();
|
| 687 | }
|
| 688 |
|
| 689 |
|
| 690 | static int __init mct_init_spi(struct device_node *np)
|
| 691 | {
|
| 692 | return mct_init_dt(np, MCT_INT_SPI);
|
| 693 | }
|
| 694 |
|
| 695 | static int __init mct_init_ppi(struct device_node *np)
|
| 696 | {
|
| 697 | return mct_init_dt(np, MCT_INT_PPI);
|
| 698 | }
|
| 699 | TIMER_OF_DECLARE(exynos4210, "samsung,exynos4210-mct", mct_init_spi);
|
| 700 | TIMER_OF_DECLARE(exynos4412, "samsung,exynos4412-mct", mct_init_ppi);
|