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Diffstat (limited to 'arch/arm/plat-spear/time.c')
| -rw-r--r-- | arch/arm/plat-spear/time.c | 245 |
1 files changed, 0 insertions, 245 deletions
diff --git a/arch/arm/plat-spear/time.c b/arch/arm/plat-spear/time.c deleted file mode 100644 index bd5c53cd6962..000000000000 --- a/arch/arm/plat-spear/time.c +++ /dev/null @@ -1,245 +0,0 @@ -/* - * arch/arm/plat-spear/time.c - * - * Copyright (C) 2010 ST Microelectronics - * Shiraz Hashim<shiraz.hashim@st.com> - * - * This file is licensed under the terms of the GNU General Public - * License version 2. This program is licensed "as is" without any - * warranty of any kind, whether express or implied. - */ - -#include <linux/clk.h> -#include <linux/clockchips.h> -#include <linux/clocksource.h> -#include <linux/err.h> -#include <linux/init.h> -#include <linux/interrupt.h> -#include <linux/ioport.h> -#include <linux/io.h> -#include <linux/kernel.h> -#include <linux/of_irq.h> -#include <linux/of_address.h> -#include <linux/time.h> -#include <linux/irq.h> -#include <asm/mach/time.h> -#include <mach/generic.h> - -/* - * We would use TIMER0 and TIMER1 as clockevent and clocksource. - * Timer0 and Timer1 both belong to same gpt block in cpu subbsystem. Further - * they share same functional clock. Any change in one's functional clock will - * also affect other timer. - */ - -#define CLKEVT 0 /* gpt0, channel0 as clockevent */ -#define CLKSRC 1 /* gpt0, channel1 as clocksource */ - -/* Register offsets, x is channel number */ -#define CR(x) ((x) * 0x80 + 0x80) -#define IR(x) ((x) * 0x80 + 0x84) -#define LOAD(x) ((x) * 0x80 + 0x88) -#define COUNT(x) ((x) * 0x80 + 0x8C) - -/* Reg bit definitions */ -#define CTRL_INT_ENABLE 0x0100 -#define CTRL_ENABLE 0x0020 -#define CTRL_ONE_SHOT 0x0010 - -#define CTRL_PRESCALER1 0x0 -#define CTRL_PRESCALER2 0x1 -#define CTRL_PRESCALER4 0x2 -#define CTRL_PRESCALER8 0x3 -#define CTRL_PRESCALER16 0x4 -#define CTRL_PRESCALER32 0x5 -#define CTRL_PRESCALER64 0x6 -#define CTRL_PRESCALER128 0x7 -#define CTRL_PRESCALER256 0x8 - -#define INT_STATUS 0x1 - -/* - * Minimum clocksource/clockevent timer range in seconds - */ -#define SPEAR_MIN_RANGE 4 - -static __iomem void *gpt_base; -static struct clk *gpt_clk; - -static void clockevent_set_mode(enum clock_event_mode mode, - struct clock_event_device *clk_event_dev); -static int clockevent_next_event(unsigned long evt, - struct clock_event_device *clk_event_dev); - -static void spear_clocksource_init(void) -{ - u32 tick_rate; - u16 val; - - /* program the prescaler (/256)*/ - writew(CTRL_PRESCALER256, gpt_base + CR(CLKSRC)); - - /* find out actual clock driving Timer */ - tick_rate = clk_get_rate(gpt_clk); - tick_rate >>= CTRL_PRESCALER256; - - writew(0xFFFF, gpt_base + LOAD(CLKSRC)); - - val = readw(gpt_base + CR(CLKSRC)); - val &= ~CTRL_ONE_SHOT; /* autoreload mode */ - val |= CTRL_ENABLE ; - writew(val, gpt_base + CR(CLKSRC)); - - /* register the clocksource */ - clocksource_mmio_init(gpt_base + COUNT(CLKSRC), "tmr1", tick_rate, - 200, 16, clocksource_mmio_readw_up); -} - -static struct clock_event_device clkevt = { - .name = "tmr0", - .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, - .set_mode = clockevent_set_mode, - .set_next_event = clockevent_next_event, - .shift = 0, /* to be computed */ -}; - -static void clockevent_set_mode(enum clock_event_mode mode, - struct clock_event_device *clk_event_dev) -{ - u32 period; - u16 val; - - /* stop the timer */ - val = readw(gpt_base + CR(CLKEVT)); - val &= ~CTRL_ENABLE; - writew(val, gpt_base + CR(CLKEVT)); - - switch (mode) { - case CLOCK_EVT_MODE_PERIODIC: - period = clk_get_rate(gpt_clk) / HZ; - period >>= CTRL_PRESCALER16; - writew(period, gpt_base + LOAD(CLKEVT)); - - val = readw(gpt_base + CR(CLKEVT)); - val &= ~CTRL_ONE_SHOT; - val |= CTRL_ENABLE | CTRL_INT_ENABLE; - writew(val, gpt_base + CR(CLKEVT)); - - break; - case CLOCK_EVT_MODE_ONESHOT: - val = readw(gpt_base + CR(CLKEVT)); - val |= CTRL_ONE_SHOT; - writew(val, gpt_base + CR(CLKEVT)); - - break; - case CLOCK_EVT_MODE_UNUSED: - case CLOCK_EVT_MODE_SHUTDOWN: - case CLOCK_EVT_MODE_RESUME: - - break; - default: - pr_err("Invalid mode requested\n"); - break; - } -} - -static int clockevent_next_event(unsigned long cycles, - struct clock_event_device *clk_event_dev) -{ - u16 val = readw(gpt_base + CR(CLKEVT)); - - if (val & CTRL_ENABLE) - writew(val & ~CTRL_ENABLE, gpt_base + CR(CLKEVT)); - - writew(cycles, gpt_base + LOAD(CLKEVT)); - - val |= CTRL_ENABLE | CTRL_INT_ENABLE; - writew(val, gpt_base + CR(CLKEVT)); - - return 0; -} - -static irqreturn_t spear_timer_interrupt(int irq, void *dev_id) -{ - struct clock_event_device *evt = &clkevt; - - writew(INT_STATUS, gpt_base + IR(CLKEVT)); - - evt->event_handler(evt); - - return IRQ_HANDLED; -} - -static struct irqaction spear_timer_irq = { - .name = "timer", - .flags = IRQF_DISABLED | IRQF_TIMER, - .handler = spear_timer_interrupt -}; - -static void __init spear_clockevent_init(int irq) -{ - u32 tick_rate; - - /* program the prescaler */ - writew(CTRL_PRESCALER16, gpt_base + CR(CLKEVT)); - - tick_rate = clk_get_rate(gpt_clk); - tick_rate >>= CTRL_PRESCALER16; - - clkevt.cpumask = cpumask_of(0); - - clockevents_config_and_register(&clkevt, tick_rate, 3, 0xfff0); - - setup_irq(irq, &spear_timer_irq); -} - -const static struct of_device_id timer_of_match[] __initconst = { - { .compatible = "st,spear-timer", }, - { }, -}; - -void __init spear_setup_of_timer(void) -{ - struct device_node *np; - int irq, ret; - - np = of_find_matching_node(NULL, timer_of_match); - if (!np) { - pr_err("%s: No timer passed via DT\n", __func__); - return; - } - - irq = irq_of_parse_and_map(np, 0); - if (!irq) { - pr_err("%s: No irq passed for timer via DT\n", __func__); - return; - } - - gpt_base = of_iomap(np, 0); - if (!gpt_base) { - pr_err("%s: of iomap failed\n", __func__); - return; - } - - gpt_clk = clk_get_sys("gpt0", NULL); - if (!gpt_clk) { - pr_err("%s:couldn't get clk for gpt\n", __func__); - goto err_iomap; - } - - ret = clk_prepare_enable(gpt_clk); - if (ret < 0) { - pr_err("%s:couldn't prepare-enable gpt clock\n", __func__); - goto err_prepare_enable_clk; - } - - spear_clockevent_init(irq); - spear_clocksource_init(); - - return; - -err_prepare_enable_clk: - clk_put(gpt_clk); -err_iomap: - iounmap(gpt_base); -} |