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![Vincent Whitchurch](/assets/img/avatar_default.png)
If the device tree indicates that the hardware requires that the processor only use certain local timers, respect that. Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Link: https://lore.kernel.org/r/20220609112738.359385-4-vincent.whitchurch@axis.com Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
701 lines
18 KiB
C
701 lines
18 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/* linux/arch/arm/mach-exynos4/mct.c
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*
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* Copyright (c) 2011 Samsung Electronics Co., Ltd.
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* http://www.samsung.com
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*
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* Exynos4 MCT(Multi-Core Timer) support
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*/
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#include <linux/interrupt.h>
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#include <linux/irq.h>
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#include <linux/err.h>
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#include <linux/clk.h>
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#include <linux/clockchips.h>
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#include <linux/cpu.h>
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#include <linux/delay.h>
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#include <linux/percpu.h>
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#include <linux/of.h>
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#include <linux/of_irq.h>
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#include <linux/of_address.h>
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#include <linux/clocksource.h>
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#include <linux/sched_clock.h>
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#define EXYNOS4_MCTREG(x) (x)
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#define EXYNOS4_MCT_G_CNT_L EXYNOS4_MCTREG(0x100)
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#define EXYNOS4_MCT_G_CNT_U EXYNOS4_MCTREG(0x104)
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#define EXYNOS4_MCT_G_CNT_WSTAT EXYNOS4_MCTREG(0x110)
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#define EXYNOS4_MCT_G_COMP0_L EXYNOS4_MCTREG(0x200)
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#define EXYNOS4_MCT_G_COMP0_U EXYNOS4_MCTREG(0x204)
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#define EXYNOS4_MCT_G_COMP0_ADD_INCR EXYNOS4_MCTREG(0x208)
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#define EXYNOS4_MCT_G_TCON EXYNOS4_MCTREG(0x240)
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#define EXYNOS4_MCT_G_INT_CSTAT EXYNOS4_MCTREG(0x244)
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#define EXYNOS4_MCT_G_INT_ENB EXYNOS4_MCTREG(0x248)
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#define EXYNOS4_MCT_G_WSTAT EXYNOS4_MCTREG(0x24C)
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#define _EXYNOS4_MCT_L_BASE EXYNOS4_MCTREG(0x300)
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#define EXYNOS4_MCT_L_BASE(x) (_EXYNOS4_MCT_L_BASE + (0x100 * (x)))
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#define EXYNOS4_MCT_L_MASK (0xffffff00)
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#define MCT_L_TCNTB_OFFSET (0x00)
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#define MCT_L_ICNTB_OFFSET (0x08)
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#define MCT_L_TCON_OFFSET (0x20)
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#define MCT_L_INT_CSTAT_OFFSET (0x30)
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#define MCT_L_INT_ENB_OFFSET (0x34)
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#define MCT_L_WSTAT_OFFSET (0x40)
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#define MCT_G_TCON_START (1 << 8)
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#define MCT_G_TCON_COMP0_AUTO_INC (1 << 1)
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#define MCT_G_TCON_COMP0_ENABLE (1 << 0)
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#define MCT_L_TCON_INTERVAL_MODE (1 << 2)
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#define MCT_L_TCON_INT_START (1 << 1)
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#define MCT_L_TCON_TIMER_START (1 << 0)
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#define TICK_BASE_CNT 1
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#ifdef CONFIG_ARM
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/* Use values higher than ARM arch timer. See 6282edb72bed. */
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#define MCT_CLKSOURCE_RATING 450
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#define MCT_CLKEVENTS_RATING 500
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#else
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#define MCT_CLKSOURCE_RATING 350
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#define MCT_CLKEVENTS_RATING 350
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#endif
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/* There are four Global timers starting with 0 offset */
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#define MCT_G0_IRQ 0
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/* Local timers count starts after global timer count */
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#define MCT_L0_IRQ 4
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/* Max number of IRQ as per DT binding document */
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#define MCT_NR_IRQS 20
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/* Max number of local timers */
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#define MCT_NR_LOCAL (MCT_NR_IRQS - MCT_L0_IRQ)
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enum {
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MCT_INT_SPI,
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MCT_INT_PPI
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};
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static void __iomem *reg_base;
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static unsigned long clk_rate;
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static unsigned int mct_int_type;
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static int mct_irqs[MCT_NR_IRQS];
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struct mct_clock_event_device {
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struct clock_event_device evt;
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unsigned long base;
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/**
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* The length of the name must be adjusted if number of
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* local timer interrupts grow over two digits
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*/
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char name[11];
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};
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static void exynos4_mct_write(unsigned int value, unsigned long offset)
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{
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unsigned long stat_addr;
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u32 mask;
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u32 i;
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writel_relaxed(value, reg_base + offset);
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if (likely(offset >= EXYNOS4_MCT_L_BASE(0))) {
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stat_addr = (offset & EXYNOS4_MCT_L_MASK) + MCT_L_WSTAT_OFFSET;
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switch (offset & ~EXYNOS4_MCT_L_MASK) {
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case MCT_L_TCON_OFFSET:
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mask = 1 << 3; /* L_TCON write status */
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break;
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case MCT_L_ICNTB_OFFSET:
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mask = 1 << 1; /* L_ICNTB write status */
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break;
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case MCT_L_TCNTB_OFFSET:
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mask = 1 << 0; /* L_TCNTB write status */
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break;
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default:
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return;
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}
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} else {
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switch (offset) {
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case EXYNOS4_MCT_G_TCON:
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stat_addr = EXYNOS4_MCT_G_WSTAT;
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mask = 1 << 16; /* G_TCON write status */
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break;
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case EXYNOS4_MCT_G_COMP0_L:
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stat_addr = EXYNOS4_MCT_G_WSTAT;
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mask = 1 << 0; /* G_COMP0_L write status */
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break;
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case EXYNOS4_MCT_G_COMP0_U:
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stat_addr = EXYNOS4_MCT_G_WSTAT;
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mask = 1 << 1; /* G_COMP0_U write status */
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break;
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case EXYNOS4_MCT_G_COMP0_ADD_INCR:
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stat_addr = EXYNOS4_MCT_G_WSTAT;
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mask = 1 << 2; /* G_COMP0_ADD_INCR w status */
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break;
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case EXYNOS4_MCT_G_CNT_L:
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stat_addr = EXYNOS4_MCT_G_CNT_WSTAT;
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mask = 1 << 0; /* G_CNT_L write status */
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break;
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case EXYNOS4_MCT_G_CNT_U:
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stat_addr = EXYNOS4_MCT_G_CNT_WSTAT;
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mask = 1 << 1; /* G_CNT_U write status */
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break;
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default:
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return;
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}
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}
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/* Wait maximum 1 ms until written values are applied */
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for (i = 0; i < loops_per_jiffy / 1000 * HZ; i++)
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if (readl_relaxed(reg_base + stat_addr) & mask) {
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writel_relaxed(mask, reg_base + stat_addr);
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return;
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}
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panic("MCT hangs after writing %d (offset:0x%lx)\n", value, offset);
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}
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/* Clocksource handling */
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static void exynos4_mct_frc_start(void)
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{
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u32 reg;
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reg = readl_relaxed(reg_base + EXYNOS4_MCT_G_TCON);
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reg |= MCT_G_TCON_START;
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exynos4_mct_write(reg, EXYNOS4_MCT_G_TCON);
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}
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/**
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* exynos4_read_count_64 - Read all 64-bits of the global counter
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*
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* This will read all 64-bits of the global counter taking care to make sure
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* that the upper and lower half match. Note that reading the MCT can be quite
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* slow (hundreds of nanoseconds) so you should use the 32-bit (lower half
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* only) version when possible.
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*
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* Returns the number of cycles in the global counter.
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*/
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static u64 exynos4_read_count_64(void)
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{
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unsigned int lo, hi;
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u32 hi2 = readl_relaxed(reg_base + EXYNOS4_MCT_G_CNT_U);
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do {
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hi = hi2;
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lo = readl_relaxed(reg_base + EXYNOS4_MCT_G_CNT_L);
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hi2 = readl_relaxed(reg_base + EXYNOS4_MCT_G_CNT_U);
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} while (hi != hi2);
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return ((u64)hi << 32) | lo;
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}
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/**
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* exynos4_read_count_32 - Read the lower 32-bits of the global counter
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*
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* This will read just the lower 32-bits of the global counter. This is marked
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* as notrace so it can be used by the scheduler clock.
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*
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* Returns the number of cycles in the global counter (lower 32 bits).
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*/
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static u32 notrace exynos4_read_count_32(void)
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{
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return readl_relaxed(reg_base + EXYNOS4_MCT_G_CNT_L);
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}
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static u64 exynos4_frc_read(struct clocksource *cs)
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{
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return exynos4_read_count_32();
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}
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static void exynos4_frc_resume(struct clocksource *cs)
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{
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exynos4_mct_frc_start();
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}
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static struct clocksource mct_frc = {
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.name = "mct-frc",
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.rating = MCT_CLKSOURCE_RATING,
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.read = exynos4_frc_read,
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.mask = CLOCKSOURCE_MASK(32),
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.flags = CLOCK_SOURCE_IS_CONTINUOUS,
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.resume = exynos4_frc_resume,
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};
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static u64 notrace exynos4_read_sched_clock(void)
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{
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return exynos4_read_count_32();
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}
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#if defined(CONFIG_ARM)
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static struct delay_timer exynos4_delay_timer;
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static cycles_t exynos4_read_current_timer(void)
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{
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BUILD_BUG_ON_MSG(sizeof(cycles_t) != sizeof(u32),
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"cycles_t needs to move to 32-bit for ARM64 usage");
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return exynos4_read_count_32();
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}
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#endif
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static int __init exynos4_clocksource_init(bool frc_shared)
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{
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/*
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* When the frc is shared, the main processer should have already
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* turned it on and we shouldn't be writing to TCON.
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*/
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if (frc_shared)
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mct_frc.resume = NULL;
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else
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exynos4_mct_frc_start();
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#if defined(CONFIG_ARM)
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exynos4_delay_timer.read_current_timer = &exynos4_read_current_timer;
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exynos4_delay_timer.freq = clk_rate;
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register_current_timer_delay(&exynos4_delay_timer);
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#endif
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if (clocksource_register_hz(&mct_frc, clk_rate))
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panic("%s: can't register clocksource\n", mct_frc.name);
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sched_clock_register(exynos4_read_sched_clock, 32, clk_rate);
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return 0;
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}
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static void exynos4_mct_comp0_stop(void)
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{
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unsigned int tcon;
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tcon = readl_relaxed(reg_base + EXYNOS4_MCT_G_TCON);
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tcon &= ~(MCT_G_TCON_COMP0_ENABLE | MCT_G_TCON_COMP0_AUTO_INC);
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exynos4_mct_write(tcon, EXYNOS4_MCT_G_TCON);
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exynos4_mct_write(0, EXYNOS4_MCT_G_INT_ENB);
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}
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static void exynos4_mct_comp0_start(bool periodic, unsigned long cycles)
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{
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unsigned int tcon;
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u64 comp_cycle;
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tcon = readl_relaxed(reg_base + EXYNOS4_MCT_G_TCON);
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if (periodic) {
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tcon |= MCT_G_TCON_COMP0_AUTO_INC;
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exynos4_mct_write(cycles, EXYNOS4_MCT_G_COMP0_ADD_INCR);
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}
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comp_cycle = exynos4_read_count_64() + cycles;
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exynos4_mct_write((u32)comp_cycle, EXYNOS4_MCT_G_COMP0_L);
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exynos4_mct_write((u32)(comp_cycle >> 32), EXYNOS4_MCT_G_COMP0_U);
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exynos4_mct_write(0x1, EXYNOS4_MCT_G_INT_ENB);
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tcon |= MCT_G_TCON_COMP0_ENABLE;
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exynos4_mct_write(tcon , EXYNOS4_MCT_G_TCON);
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}
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static int exynos4_comp_set_next_event(unsigned long cycles,
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struct clock_event_device *evt)
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{
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exynos4_mct_comp0_start(false, cycles);
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return 0;
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}
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static int mct_set_state_shutdown(struct clock_event_device *evt)
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{
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exynos4_mct_comp0_stop();
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return 0;
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}
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static int mct_set_state_periodic(struct clock_event_device *evt)
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{
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unsigned long cycles_per_jiffy;
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cycles_per_jiffy = (((unsigned long long)NSEC_PER_SEC / HZ * evt->mult)
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>> evt->shift);
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exynos4_mct_comp0_stop();
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exynos4_mct_comp0_start(true, cycles_per_jiffy);
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return 0;
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}
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static struct clock_event_device mct_comp_device = {
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.name = "mct-comp",
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.features = CLOCK_EVT_FEAT_PERIODIC |
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CLOCK_EVT_FEAT_ONESHOT,
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.rating = 250,
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.set_next_event = exynos4_comp_set_next_event,
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.set_state_periodic = mct_set_state_periodic,
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.set_state_shutdown = mct_set_state_shutdown,
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.set_state_oneshot = mct_set_state_shutdown,
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.set_state_oneshot_stopped = mct_set_state_shutdown,
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.tick_resume = mct_set_state_shutdown,
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};
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static irqreturn_t exynos4_mct_comp_isr(int irq, void *dev_id)
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{
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struct clock_event_device *evt = dev_id;
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exynos4_mct_write(0x1, EXYNOS4_MCT_G_INT_CSTAT);
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evt->event_handler(evt);
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return IRQ_HANDLED;
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}
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static int exynos4_clockevent_init(void)
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{
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mct_comp_device.cpumask = cpumask_of(0);
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clockevents_config_and_register(&mct_comp_device, clk_rate,
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0xf, 0xffffffff);
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if (request_irq(mct_irqs[MCT_G0_IRQ], exynos4_mct_comp_isr,
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IRQF_TIMER | IRQF_IRQPOLL, "mct_comp_irq",
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&mct_comp_device))
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pr_err("%s: request_irq() failed\n", "mct_comp_irq");
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return 0;
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}
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static DEFINE_PER_CPU(struct mct_clock_event_device, percpu_mct_tick);
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/* Clock event handling */
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static void exynos4_mct_tick_stop(struct mct_clock_event_device *mevt)
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{
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unsigned long tmp;
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unsigned long mask = MCT_L_TCON_INT_START | MCT_L_TCON_TIMER_START;
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unsigned long offset = mevt->base + MCT_L_TCON_OFFSET;
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tmp = readl_relaxed(reg_base + offset);
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if (tmp & mask) {
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tmp &= ~mask;
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exynos4_mct_write(tmp, offset);
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}
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}
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static void exynos4_mct_tick_start(unsigned long cycles,
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struct mct_clock_event_device *mevt)
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{
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unsigned long tmp;
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exynos4_mct_tick_stop(mevt);
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tmp = (1 << 31) | cycles; /* MCT_L_UPDATE_ICNTB */
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/* update interrupt count buffer */
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exynos4_mct_write(tmp, mevt->base + MCT_L_ICNTB_OFFSET);
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/* enable MCT tick interrupt */
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exynos4_mct_write(0x1, mevt->base + MCT_L_INT_ENB_OFFSET);
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tmp = readl_relaxed(reg_base + mevt->base + MCT_L_TCON_OFFSET);
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tmp |= MCT_L_TCON_INT_START | MCT_L_TCON_TIMER_START |
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MCT_L_TCON_INTERVAL_MODE;
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exynos4_mct_write(tmp, mevt->base + MCT_L_TCON_OFFSET);
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}
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static void exynos4_mct_tick_clear(struct mct_clock_event_device *mevt)
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{
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/* Clear the MCT tick interrupt */
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if (readl_relaxed(reg_base + mevt->base + MCT_L_INT_CSTAT_OFFSET) & 1)
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exynos4_mct_write(0x1, mevt->base + MCT_L_INT_CSTAT_OFFSET);
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}
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static int exynos4_tick_set_next_event(unsigned long cycles,
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struct clock_event_device *evt)
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{
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struct mct_clock_event_device *mevt;
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mevt = container_of(evt, struct mct_clock_event_device, evt);
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exynos4_mct_tick_start(cycles, mevt);
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return 0;
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}
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static int set_state_shutdown(struct clock_event_device *evt)
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{
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struct mct_clock_event_device *mevt;
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mevt = container_of(evt, struct mct_clock_event_device, evt);
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exynos4_mct_tick_stop(mevt);
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exynos4_mct_tick_clear(mevt);
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return 0;
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}
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static int set_state_periodic(struct clock_event_device *evt)
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{
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struct mct_clock_event_device *mevt;
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unsigned long cycles_per_jiffy;
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mevt = container_of(evt, struct mct_clock_event_device, evt);
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cycles_per_jiffy = (((unsigned long long)NSEC_PER_SEC / HZ * evt->mult)
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>> evt->shift);
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exynos4_mct_tick_stop(mevt);
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exynos4_mct_tick_start(cycles_per_jiffy, mevt);
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return 0;
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}
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static irqreturn_t exynos4_mct_tick_isr(int irq, void *dev_id)
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{
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struct mct_clock_event_device *mevt = dev_id;
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struct clock_event_device *evt = &mevt->evt;
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/*
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|
* This is for supporting oneshot mode.
|
|
* Mct would generate interrupt periodically
|
|
* without explicit stopping.
|
|
*/
|
|
if (!clockevent_state_periodic(&mevt->evt))
|
|
exynos4_mct_tick_stop(mevt);
|
|
|
|
exynos4_mct_tick_clear(mevt);
|
|
|
|
evt->event_handler(evt);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static int exynos4_mct_starting_cpu(unsigned int cpu)
|
|
{
|
|
struct mct_clock_event_device *mevt =
|
|
per_cpu_ptr(&percpu_mct_tick, cpu);
|
|
struct clock_event_device *evt = &mevt->evt;
|
|
|
|
snprintf(mevt->name, sizeof(mevt->name), "mct_tick%d", cpu);
|
|
|
|
evt->name = mevt->name;
|
|
evt->cpumask = cpumask_of(cpu);
|
|
evt->set_next_event = exynos4_tick_set_next_event;
|
|
evt->set_state_periodic = set_state_periodic;
|
|
evt->set_state_shutdown = set_state_shutdown;
|
|
evt->set_state_oneshot = set_state_shutdown;
|
|
evt->set_state_oneshot_stopped = set_state_shutdown;
|
|
evt->tick_resume = set_state_shutdown;
|
|
evt->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT |
|
|
CLOCK_EVT_FEAT_PERCPU;
|
|
evt->rating = MCT_CLKEVENTS_RATING;
|
|
|
|
exynos4_mct_write(TICK_BASE_CNT, mevt->base + MCT_L_TCNTB_OFFSET);
|
|
|
|
if (mct_int_type == MCT_INT_SPI) {
|
|
|
|
if (evt->irq == -1)
|
|
return -EIO;
|
|
|
|
irq_force_affinity(evt->irq, cpumask_of(cpu));
|
|
enable_irq(evt->irq);
|
|
} else {
|
|
enable_percpu_irq(mct_irqs[MCT_L0_IRQ], 0);
|
|
}
|
|
clockevents_config_and_register(evt, clk_rate / (TICK_BASE_CNT + 1),
|
|
0xf, 0x7fffffff);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int exynos4_mct_dying_cpu(unsigned int cpu)
|
|
{
|
|
struct mct_clock_event_device *mevt =
|
|
per_cpu_ptr(&percpu_mct_tick, cpu);
|
|
struct clock_event_device *evt = &mevt->evt;
|
|
|
|
evt->set_state_shutdown(evt);
|
|
if (mct_int_type == MCT_INT_SPI) {
|
|
if (evt->irq != -1)
|
|
disable_irq_nosync(evt->irq);
|
|
exynos4_mct_write(0x1, mevt->base + MCT_L_INT_CSTAT_OFFSET);
|
|
} else {
|
|
disable_percpu_irq(mct_irqs[MCT_L0_IRQ]);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int __init exynos4_timer_resources(struct device_node *np)
|
|
{
|
|
struct clk *mct_clk, *tick_clk;
|
|
|
|
reg_base = of_iomap(np, 0);
|
|
if (!reg_base)
|
|
panic("%s: unable to ioremap mct address space\n", __func__);
|
|
|
|
tick_clk = of_clk_get_by_name(np, "fin_pll");
|
|
if (IS_ERR(tick_clk))
|
|
panic("%s: unable to determine tick clock rate\n", __func__);
|
|
clk_rate = clk_get_rate(tick_clk);
|
|
|
|
mct_clk = of_clk_get_by_name(np, "mct");
|
|
if (IS_ERR(mct_clk))
|
|
panic("%s: unable to retrieve mct clock instance\n", __func__);
|
|
clk_prepare_enable(mct_clk);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* exynos4_timer_interrupts - initialize MCT interrupts
|
|
* @np: device node for MCT
|
|
* @int_type: interrupt type, MCT_INT_PPI or MCT_INT_SPI
|
|
* @local_idx: array mapping CPU numbers to local timer indices
|
|
* @nr_local: size of @local_idx array
|
|
*/
|
|
static int __init exynos4_timer_interrupts(struct device_node *np,
|
|
unsigned int int_type,
|
|
const u32 *local_idx,
|
|
size_t nr_local)
|
|
{
|
|
int nr_irqs, i, err, cpu;
|
|
|
|
mct_int_type = int_type;
|
|
|
|
/* This driver uses only one global timer interrupt */
|
|
mct_irqs[MCT_G0_IRQ] = irq_of_parse_and_map(np, MCT_G0_IRQ);
|
|
|
|
/*
|
|
* Find out the number of local irqs specified. The local
|
|
* timer irqs are specified after the four global timer
|
|
* irqs are specified.
|
|
*/
|
|
nr_irqs = of_irq_count(np);
|
|
if (nr_irqs > ARRAY_SIZE(mct_irqs)) {
|
|
pr_err("exynos-mct: too many (%d) interrupts configured in DT\n",
|
|
nr_irqs);
|
|
nr_irqs = ARRAY_SIZE(mct_irqs);
|
|
}
|
|
for (i = MCT_L0_IRQ; i < nr_irqs; i++)
|
|
mct_irqs[i] = irq_of_parse_and_map(np, i);
|
|
|
|
if (mct_int_type == MCT_INT_PPI) {
|
|
|
|
err = request_percpu_irq(mct_irqs[MCT_L0_IRQ],
|
|
exynos4_mct_tick_isr, "MCT",
|
|
&percpu_mct_tick);
|
|
WARN(err, "MCT: can't request IRQ %d (%d)\n",
|
|
mct_irqs[MCT_L0_IRQ], err);
|
|
} else {
|
|
for_each_possible_cpu(cpu) {
|
|
int mct_irq;
|
|
unsigned int irq_idx;
|
|
struct mct_clock_event_device *pcpu_mevt =
|
|
per_cpu_ptr(&percpu_mct_tick, cpu);
|
|
|
|
if (cpu >= nr_local) {
|
|
err = -EINVAL;
|
|
goto out_irq;
|
|
}
|
|
|
|
irq_idx = MCT_L0_IRQ + local_idx[cpu];
|
|
|
|
pcpu_mevt->evt.irq = -1;
|
|
if (irq_idx >= ARRAY_SIZE(mct_irqs))
|
|
break;
|
|
mct_irq = mct_irqs[irq_idx];
|
|
|
|
irq_set_status_flags(mct_irq, IRQ_NOAUTOEN);
|
|
if (request_irq(mct_irq,
|
|
exynos4_mct_tick_isr,
|
|
IRQF_TIMER | IRQF_NOBALANCING,
|
|
pcpu_mevt->name, pcpu_mevt)) {
|
|
pr_err("exynos-mct: cannot register IRQ (cpu%d)\n",
|
|
cpu);
|
|
|
|
continue;
|
|
}
|
|
pcpu_mevt->evt.irq = mct_irq;
|
|
}
|
|
}
|
|
|
|
for_each_possible_cpu(cpu) {
|
|
struct mct_clock_event_device *mevt = per_cpu_ptr(&percpu_mct_tick, cpu);
|
|
|
|
if (cpu >= nr_local) {
|
|
err = -EINVAL;
|
|
goto out_irq;
|
|
}
|
|
|
|
mevt->base = EXYNOS4_MCT_L_BASE(local_idx[cpu]);
|
|
}
|
|
|
|
/* Install hotplug callbacks which configure the timer on this CPU */
|
|
err = cpuhp_setup_state(CPUHP_AP_EXYNOS4_MCT_TIMER_STARTING,
|
|
"clockevents/exynos4/mct_timer:starting",
|
|
exynos4_mct_starting_cpu,
|
|
exynos4_mct_dying_cpu);
|
|
if (err)
|
|
goto out_irq;
|
|
|
|
return 0;
|
|
|
|
out_irq:
|
|
if (mct_int_type == MCT_INT_PPI) {
|
|
free_percpu_irq(mct_irqs[MCT_L0_IRQ], &percpu_mct_tick);
|
|
} else {
|
|
for_each_possible_cpu(cpu) {
|
|
struct mct_clock_event_device *pcpu_mevt =
|
|
per_cpu_ptr(&percpu_mct_tick, cpu);
|
|
|
|
if (pcpu_mevt->evt.irq != -1) {
|
|
free_irq(pcpu_mevt->evt.irq, pcpu_mevt);
|
|
pcpu_mevt->evt.irq = -1;
|
|
}
|
|
}
|
|
}
|
|
return err;
|
|
}
|
|
|
|
static int __init mct_init_dt(struct device_node *np, unsigned int int_type)
|
|
{
|
|
bool frc_shared = of_property_read_bool(np, "samsung,frc-shared");
|
|
u32 local_idx[MCT_NR_LOCAL] = {0};
|
|
int nr_local;
|
|
int ret;
|
|
|
|
nr_local = of_property_count_u32_elems(np, "samsung,local-timers");
|
|
if (nr_local == 0)
|
|
return -EINVAL;
|
|
if (nr_local > 0) {
|
|
if (nr_local > ARRAY_SIZE(local_idx))
|
|
return -EINVAL;
|
|
|
|
ret = of_property_read_u32_array(np, "samsung,local-timers",
|
|
local_idx, nr_local);
|
|
if (ret)
|
|
return ret;
|
|
} else {
|
|
int i;
|
|
|
|
nr_local = ARRAY_SIZE(local_idx);
|
|
for (i = 0; i < nr_local; i++)
|
|
local_idx[i] = i;
|
|
}
|
|
|
|
ret = exynos4_timer_resources(np);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = exynos4_timer_interrupts(np, int_type, local_idx, nr_local);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = exynos4_clocksource_init(frc_shared);
|
|
if (ret)
|
|
return ret;
|
|
|
|
/*
|
|
* When the FRC is shared with a main processor, this secondary
|
|
* processor cannot use the global comparator.
|
|
*/
|
|
if (frc_shared)
|
|
return ret;
|
|
|
|
return exynos4_clockevent_init();
|
|
}
|
|
|
|
|
|
static int __init mct_init_spi(struct device_node *np)
|
|
{
|
|
return mct_init_dt(np, MCT_INT_SPI);
|
|
}
|
|
|
|
static int __init mct_init_ppi(struct device_node *np)
|
|
{
|
|
return mct_init_dt(np, MCT_INT_PPI);
|
|
}
|
|
TIMER_OF_DECLARE(exynos4210, "samsung,exynos4210-mct", mct_init_spi);
|
|
TIMER_OF_DECLARE(exynos4412, "samsung,exynos4412-mct", mct_init_ppi);
|