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-rw-r--r--arch/mips/ralink/Kconfig10
-rw-r--r--arch/mips/ralink/Makefile4
-rw-r--r--arch/mips/ralink/Platform1
-rw-r--r--arch/mips/ralink/cevt-rt3352.c145
-rw-r--r--arch/mips/ralink/clk.c1
-rw-r--r--arch/mips/ralink/common.h2
-rw-r--r--arch/mips/ralink/mt7620.c205
-rw-r--r--arch/mips/ralink/of.c3
-rw-r--r--arch/mips/ralink/reset.c62
-rw-r--r--arch/mips/ralink/timer.c185
10 files changed, 592 insertions, 26 deletions
diff --git a/arch/mips/ralink/Kconfig b/arch/mips/ralink/Kconfig
index 026e823d871..424f03496d1 100644
--- a/arch/mips/ralink/Kconfig
+++ b/arch/mips/ralink/Kconfig
@@ -1,5 +1,12 @@
if RALINK
+config CLKEVT_RT3352
+ bool
+ depends on SOC_RT305X || SOC_MT7620
+ default y
+ select CLKSRC_OF
+ select CLKSRC_MMIO
+
choice
prompt "Ralink SoC selection"
default SOC_RT305X
@@ -19,9 +26,12 @@ choice
bool "RT3883"
select USB_ARCH_HAS_OHCI
select USB_ARCH_HAS_EHCI
+ select HW_HAS_PCI
config SOC_MT7620
bool "MT7620"
+ select USB_ARCH_HAS_OHCI
+ select USB_ARCH_HAS_EHCI
endchoice
diff --git a/arch/mips/ralink/Makefile b/arch/mips/ralink/Makefile
index 38cf1a880aa..98ae349827b 100644
--- a/arch/mips/ralink/Makefile
+++ b/arch/mips/ralink/Makefile
@@ -6,7 +6,9 @@
# Copyright (C) 2009-2011 Gabor Juhos <juhosg@openwrt.org>
# Copyright (C) 2013 John Crispin <blogic@openwrt.org>
-obj-y := prom.o of.o reset.o clk.o irq.o
+obj-y := prom.o of.o reset.o clk.o irq.o timer.o
+
+obj-$(CONFIG_CLKEVT_RT3352) += cevt-rt3352.o
obj-$(CONFIG_SOC_RT288X) += rt288x.o
obj-$(CONFIG_SOC_RT305X) += rt305x.o
diff --git a/arch/mips/ralink/Platform b/arch/mips/ralink/Platform
index cda4b6645c5..6d9c8c499f9 100644
--- a/arch/mips/ralink/Platform
+++ b/arch/mips/ralink/Platform
@@ -26,3 +26,4 @@ cflags-$(CONFIG_SOC_RT3883) += -I$(srctree)/arch/mips/include/asm/mach-ralink/rt
# Ralink MT7620
#
load-$(CONFIG_SOC_MT7620) += 0xffffffff80000000
+cflags-$(CONFIG_SOC_MT7620) += -I$(srctree)/arch/mips/include/asm/mach-ralink/mt7620
diff --git a/arch/mips/ralink/cevt-rt3352.c b/arch/mips/ralink/cevt-rt3352.c
new file mode 100644
index 00000000000..cc17566d193
--- /dev/null
+++ b/arch/mips/ralink/cevt-rt3352.c
@@ -0,0 +1,145 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2013 by John Crispin <blogic@openwrt.org>
+ */
+
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/interrupt.h>
+#include <linux/reset.h>
+#include <linux/init.h>
+#include <linux/time.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+
+#include <asm/mach-ralink/ralink_regs.h>
+
+#define SYSTICK_FREQ (50 * 1000)
+
+#define SYSTICK_CONFIG 0x00
+#define SYSTICK_COMPARE 0x04
+#define SYSTICK_COUNT 0x08
+
+/* route systick irq to mips irq 7 instead of the r4k-timer */
+#define CFG_EXT_STK_EN 0x2
+/* enable the counter */
+#define CFG_CNT_EN 0x1
+
+struct systick_device {
+ void __iomem *membase;
+ struct clock_event_device dev;
+ int irq_requested;
+ int freq_scale;
+};
+
+static void systick_set_clock_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt);
+
+static int systick_next_event(unsigned long delta,
+ struct clock_event_device *evt)
+{
+ struct systick_device *sdev;
+ u32 count;
+
+ sdev = container_of(evt, struct systick_device, dev);
+ count = ioread32(sdev->membase + SYSTICK_COUNT);
+ count = (count + delta) % SYSTICK_FREQ;
+ iowrite32(count + delta, sdev->membase + SYSTICK_COMPARE);
+
+ return 0;
+}
+
+static void systick_event_handler(struct clock_event_device *dev)
+{
+ /* noting to do here */
+}
+
+static irqreturn_t systick_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *dev = (struct clock_event_device *) dev_id;
+
+ dev->event_handler(dev);
+
+ return IRQ_HANDLED;
+}
+
+static struct systick_device systick = {
+ .dev = {
+ /*
+ * cevt-r4k uses 300, make sure systick
+ * gets used if available
+ */
+ .rating = 310,
+ .features = CLOCK_EVT_FEAT_ONESHOT,
+ .set_next_event = systick_next_event,
+ .set_mode = systick_set_clock_mode,
+ .event_handler = systick_event_handler,
+ },
+};
+
+static struct irqaction systick_irqaction = {
+ .handler = systick_interrupt,
+ .flags = IRQF_PERCPU | IRQF_TIMER,
+ .dev_id = &systick.dev,
+};
+
+static void systick_set_clock_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt)
+{
+ struct systick_device *sdev;
+
+ sdev = container_of(evt, struct systick_device, dev);
+
+ switch (mode) {
+ case CLOCK_EVT_MODE_ONESHOT:
+ if (!sdev->irq_requested)
+ setup_irq(systick.dev.irq, &systick_irqaction);
+ sdev->irq_requested = 1;
+ iowrite32(CFG_EXT_STK_EN | CFG_CNT_EN,
+ systick.membase + SYSTICK_CONFIG);
+ break;
+
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ if (sdev->irq_requested)
+ free_irq(systick.dev.irq, &systick_irqaction);
+ sdev->irq_requested = 0;
+ iowrite32(0, systick.membase + SYSTICK_CONFIG);
+ break;
+
+ default:
+ pr_err("%s: Unhandeled mips clock_mode\n", systick.dev.name);
+ break;
+ }
+}
+
+static void __init ralink_systick_init(struct device_node *np)
+{
+ systick.membase = of_iomap(np, 0);
+ if (!systick.membase)
+ return;
+
+ systick_irqaction.name = np->name;
+ systick.dev.name = np->name;
+ clockevents_calc_mult_shift(&systick.dev, SYSTICK_FREQ, 60);
+ systick.dev.max_delta_ns = clockevent_delta2ns(0x7fff, &systick.dev);
+ systick.dev.min_delta_ns = clockevent_delta2ns(0x3, &systick.dev);
+ systick.dev.irq = irq_of_parse_and_map(np, 0);
+ if (!systick.dev.irq) {
+ pr_err("%s: request_irq failed", np->name);
+ return;
+ }
+
+ clocksource_mmio_init(systick.membase + SYSTICK_COUNT, np->name,
+ SYSTICK_FREQ, 301, 16, clocksource_mmio_readl_up);
+
+ clockevents_register_device(&systick.dev);
+
+ pr_info("%s: runing - mult: %d, shift: %d\n",
+ np->name, systick.dev.mult, systick.dev.shift);
+}
+
+CLOCKSOURCE_OF_DECLARE(systick, "ralink,cevt-systick", ralink_systick_init);
diff --git a/arch/mips/ralink/clk.c b/arch/mips/ralink/clk.c
index 8dfa22ff300..bba0cdfd83b 100644
--- a/arch/mips/ralink/clk.c
+++ b/arch/mips/ralink/clk.c
@@ -69,4 +69,5 @@ void __init plat_time_init(void)
pr_info("CPU Clock: %ldMHz\n", clk_get_rate(clk) / 1000000);
mips_hpt_frequency = clk_get_rate(clk) / 2;
clk_put(clk);
+ clocksource_of_init();
}
diff --git a/arch/mips/ralink/common.h b/arch/mips/ralink/common.h
index 83144c3fc5a..42dfd6100a2 100644
--- a/arch/mips/ralink/common.h
+++ b/arch/mips/ralink/common.h
@@ -46,6 +46,8 @@ extern void ralink_of_remap(void);
extern void ralink_clk_init(void);
extern void ralink_clk_add(const char *dev, unsigned long rate);
+extern void ralink_rst_init(void);
+
extern void prom_soc_init(struct ralink_soc_info *soc_info);
__iomem void *plat_of_remap_node(const char *node);
diff --git a/arch/mips/ralink/mt7620.c b/arch/mips/ralink/mt7620.c
index 0018b1a661f..d217509e530 100644
--- a/arch/mips/ralink/mt7620.c
+++ b/arch/mips/ralink/mt7620.c
@@ -23,9 +23,6 @@
/* does the board have sdram or ddram */
static int dram_type;
-/* the pll dividers */
-static u32 mt7620_clk_divider[] = { 2, 3, 4, 8 };
-
static struct ralink_pinmux_grp mode_mux[] = {
{
.name = "i2c",
@@ -140,34 +137,189 @@ struct ralink_pinmux rt_gpio_pinmux = {
.uart_mask = MT7620_GPIO_MODE_UART0_MASK,
};
-void __init ralink_clk_init(void)
+static __init u32
+mt7620_calc_rate(u32 ref_rate, u32 mul, u32 div)
{
- unsigned long cpu_rate, sys_rate;
- u32 c0 = rt_sysc_r32(SYSC_REG_CPLL_CONFIG0);
- u32 c1 = rt_sysc_r32(SYSC_REG_CPLL_CONFIG1);
- u32 swconfig = (c0 >> CPLL_SW_CONFIG_SHIFT) & CPLL_SW_CONFIG_MASK;
- u32 cpu_clk = (c1 >> CPLL_CPU_CLK_SHIFT) & CPLL_CPU_CLK_MASK;
-
- if (cpu_clk) {
- cpu_rate = 480000000;
- } else if (!swconfig) {
- cpu_rate = 600000000;
- } else {
- u32 m = (c0 >> CPLL_MULT_RATIO_SHIFT) & CPLL_MULT_RATIO;
- u32 d = (c0 >> CPLL_DIV_RATIO_SHIFT) & CPLL_DIV_RATIO;
+ u64 t;
- cpu_rate = ((40 * (m + 24)) / mt7620_clk_divider[d]) * 1000000;
- }
+ t = ref_rate;
+ t *= mul;
+ do_div(t, div);
+
+ return t;
+}
+
+#define MHZ(x) ((x) * 1000 * 1000)
+
+static __init unsigned long
+mt7620_get_xtal_rate(void)
+{
+ u32 reg;
+
+ reg = rt_sysc_r32(SYSC_REG_SYSTEM_CONFIG0);
+ if (reg & SYSCFG0_XTAL_FREQ_SEL)
+ return MHZ(40);
+
+ return MHZ(20);
+}
+
+static __init unsigned long
+mt7620_get_periph_rate(unsigned long xtal_rate)
+{
+ u32 reg;
+
+ reg = rt_sysc_r32(SYSC_REG_CLKCFG0);
+ if (reg & CLKCFG0_PERI_CLK_SEL)
+ return xtal_rate;
+
+ return MHZ(40);
+}
+
+static const u32 mt7620_clk_divider[] __initconst = { 2, 3, 4, 8 };
+
+static __init unsigned long
+mt7620_get_cpu_pll_rate(unsigned long xtal_rate)
+{
+ u32 reg;
+ u32 mul;
+ u32 div;
+
+ reg = rt_sysc_r32(SYSC_REG_CPLL_CONFIG0);
+ if (reg & CPLL_CFG0_BYPASS_REF_CLK)
+ return xtal_rate;
+
+ if ((reg & CPLL_CFG0_SW_CFG) == 0)
+ return MHZ(600);
+
+ mul = (reg >> CPLL_CFG0_PLL_MULT_RATIO_SHIFT) &
+ CPLL_CFG0_PLL_MULT_RATIO_MASK;
+ mul += 24;
+ if (reg & CPLL_CFG0_LC_CURFCK)
+ mul *= 2;
+
+ div = (reg >> CPLL_CFG0_PLL_DIV_RATIO_SHIFT) &
+ CPLL_CFG0_PLL_DIV_RATIO_MASK;
+
+ WARN_ON(div >= ARRAY_SIZE(mt7620_clk_divider));
+
+ return mt7620_calc_rate(xtal_rate, mul, mt7620_clk_divider[div]);
+}
+
+static __init unsigned long
+mt7620_get_pll_rate(unsigned long xtal_rate, unsigned long cpu_pll_rate)
+{
+ u32 reg;
+
+ reg = rt_sysc_r32(SYSC_REG_CPLL_CONFIG1);
+ if (reg & CPLL_CFG1_CPU_AUX1)
+ return xtal_rate;
+
+ if (reg & CPLL_CFG1_CPU_AUX0)
+ return MHZ(480);
+ return cpu_pll_rate;
+}
+
+static __init unsigned long
+mt7620_get_cpu_rate(unsigned long pll_rate)
+{
+ u32 reg;
+ u32 mul;
+ u32 div;
+
+ reg = rt_sysc_r32(SYSC_REG_CPU_SYS_CLKCFG);
+
+ mul = reg & CPU_SYS_CLKCFG_CPU_FFRAC_MASK;
+ div = (reg >> CPU_SYS_CLKCFG_CPU_FDIV_SHIFT) &
+ CPU_SYS_CLKCFG_CPU_FDIV_MASK;
+
+ return mt7620_calc_rate(pll_rate, mul, div);
+}
+
+static const u32 mt7620_ocp_dividers[16] __initconst = {
+ [CPU_SYS_CLKCFG_OCP_RATIO_2] = 2,
+ [CPU_SYS_CLKCFG_OCP_RATIO_3] = 3,
+ [CPU_SYS_CLKCFG_OCP_RATIO_4] = 4,
+ [CPU_SYS_CLKCFG_OCP_RATIO_5] = 5,
+ [CPU_SYS_CLKCFG_OCP_RATIO_10] = 10,
+};
+
+static __init unsigned long
+mt7620_get_dram_rate(unsigned long pll_rate)
+{
if (dram_type == SYSCFG0_DRAM_TYPE_SDRAM)
- sys_rate = cpu_rate / 4;
- else
- sys_rate = cpu_rate / 3;
+ return pll_rate / 4;
+
+ return pll_rate / 3;
+}
+
+static __init unsigned long
+mt7620_get_sys_rate(unsigned long cpu_rate)
+{
+ u32 reg;
+ u32 ocp_ratio;
+ u32 div;
+
+ reg = rt_sysc_r32(SYSC_REG_CPU_SYS_CLKCFG);
+
+ ocp_ratio = (reg >> CPU_SYS_CLKCFG_OCP_RATIO_SHIFT) &
+ CPU_SYS_CLKCFG_OCP_RATIO_MASK;
+
+ if (WARN_ON(ocp_ratio >= ARRAY_SIZE(mt7620_ocp_dividers)))
+ return cpu_rate;
+
+ div = mt7620_ocp_dividers[ocp_ratio];
+ if (WARN(!div, "invalid divider for OCP ratio %u", ocp_ratio))
+ return cpu_rate;
+
+ return cpu_rate / div;
+}
+
+void __init ralink_clk_init(void)
+{
+ unsigned long xtal_rate;
+ unsigned long cpu_pll_rate;
+ unsigned long pll_rate;
+ unsigned long cpu_rate;
+ unsigned long sys_rate;
+ unsigned long dram_rate;
+ unsigned long periph_rate;
+
+ xtal_rate = mt7620_get_xtal_rate();
+
+ cpu_pll_rate = mt7620_get_cpu_pll_rate(xtal_rate);
+ pll_rate = mt7620_get_pll_rate(xtal_rate, cpu_pll_rate);
+
+ cpu_rate = mt7620_get_cpu_rate(pll_rate);
+ dram_rate = mt7620_get_dram_rate(pll_rate);
+ sys_rate = mt7620_get_sys_rate(cpu_rate);
+ periph_rate = mt7620_get_periph_rate(xtal_rate);
+
+#define RFMT(label) label ":%lu.%03luMHz "
+#define RINT(x) ((x) / 1000000)
+#define RFRAC(x) (((x) / 1000) % 1000)
+
+ pr_debug(RFMT("XTAL") RFMT("CPU_PLL") RFMT("PLL"),
+ RINT(xtal_rate), RFRAC(xtal_rate),
+ RINT(cpu_pll_rate), RFRAC(cpu_pll_rate),
+ RINT(pll_rate), RFRAC(pll_rate));
+
+ pr_debug(RFMT("CPU") RFMT("DRAM") RFMT("SYS") RFMT("PERIPH"),
+ RINT(cpu_rate), RFRAC(cpu_rate),
+ RINT(dram_rate), RFRAC(dram_rate),
+ RINT(sys_rate), RFRAC(sys_rate),
+ RINT(periph_rate), RFRAC(periph_rate));
+
+#undef RFRAC
+#undef RINT
+#undef RFMT
ralink_clk_add("cpu", cpu_rate);
- ralink_clk_add("10000100.timer", 40000000);
- ralink_clk_add("10000500.uart", 40000000);
- ralink_clk_add("10000c00.uartlite", 40000000);
+ ralink_clk_add("10000100.timer", periph_rate);
+ ralink_clk_add("10000120.watchdog", periph_rate);
+ ralink_clk_add("10000500.uart", periph_rate);
+ ralink_clk_add("10000b00.spi", sys_rate);
+ ralink_clk_add("10000c00.uartlite", periph_rate);
}
void __init ralink_of_remap(void)
@@ -214,16 +366,19 @@ void prom_soc_init(struct ralink_soc_info *soc_info)
switch (dram_type) {
case SYSCFG0_DRAM_TYPE_SDRAM:
+ pr_info("Board has SDRAM\n");
soc_info->mem_size_min = MT7620_SDRAM_SIZE_MIN;
soc_info->mem_size_max = MT7620_SDRAM_SIZE_MAX;
break;
case SYSCFG0_DRAM_TYPE_DDR1:
+ pr_info("Board has DDR1\n");
soc_info->mem_size_min = MT7620_DDR1_SIZE_MIN;
soc_info->mem_size_max = MT7620_DDR1_SIZE_MAX;
break;
case SYSCFG0_DRAM_TYPE_DDR2:
+ pr_info("Board has DDR2\n");
soc_info->mem_size_min = MT7620_DDR2_SIZE_MIN;
soc_info->mem_size_max = MT7620_DDR2_SIZE_MAX;
break;
diff --git a/arch/mips/ralink/of.c b/arch/mips/ralink/of.c
index f25ea5b4505..ce38d11f9da 100644
--- a/arch/mips/ralink/of.c
+++ b/arch/mips/ralink/of.c
@@ -110,6 +110,9 @@ static int __init plat_of_setup(void)
if (of_platform_populate(NULL, of_ids, NULL, NULL))
panic("failed to populate DT\n");
+ /* make sure ithat the reset controller is setup early */
+ ralink_rst_init();
+
return 0;
}
diff --git a/arch/mips/ralink/reset.c b/arch/mips/ralink/reset.c
index 22120e512e7..55c7ec59df3 100644
--- a/arch/mips/ralink/reset.c
+++ b/arch/mips/ralink/reset.c
@@ -10,6 +10,8 @@
#include <linux/pm.h>
#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/reset-controller.h>
#include <asm/reboot.h>
@@ -19,6 +21,66 @@
#define SYSC_REG_RESET_CTRL 0x034
#define RSTCTL_RESET_SYSTEM BIT(0)
+static int ralink_assert_device(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ u32 val;
+
+ if (id < 8)
+ return -1;
+
+ val = rt_sysc_r32(SYSC_REG_RESET_CTRL);
+ val |= BIT(id);
+ rt_sysc_w32(val, SYSC_REG_RESET_CTRL);
+
+ return 0;
+}
+
+static int ralink_deassert_device(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ u32 val;
+
+ if (id < 8)
+ return -1;
+
+ val = rt_sysc_r32(SYSC_REG_RESET_CTRL);
+ val &= ~BIT(id);
+ rt_sysc_w32(val, SYSC_REG_RESET_CTRL);
+
+ return 0;
+}
+
+static int ralink_reset_device(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ ralink_assert_device(rcdev, id);
+ return ralink_deassert_device(rcdev, id);
+}
+
+static struct reset_control_ops reset_ops = {
+ .reset = ralink_reset_device,
+ .assert = ralink_assert_device,
+ .deassert = ralink_deassert_device,
+};
+
+static struct reset_controller_dev reset_dev = {
+ .ops = &reset_ops,
+ .owner = THIS_MODULE,
+ .nr_resets = 32,
+ .of_reset_n_cells = 1,
+};
+
+void ralink_rst_init(void)
+{
+ reset_dev.of_node = of_find_compatible_node(NULL, NULL,
+ "ralink,rt2880-reset");
+ if (!reset_dev.of_node)
+ pr_err("Failed to find reset controller node");
+ else
+ reset_controller_register(&reset_dev);
+}
+
static void ralink_restart(char *command)
{
local_irq_disable();
diff --git a/arch/mips/ralink/timer.c b/arch/mips/ralink/timer.c
new file mode 100644
index 00000000000..e49241a2c39
--- /dev/null
+++ b/arch/mips/ralink/timer.c
@@ -0,0 +1,185 @@
+/*
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ *
+ * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
+*/
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/timer.h>
+#include <linux/of_gpio.h>
+#include <linux/clk.h>
+
+#include <asm/mach-ralink/ralink_regs.h>
+
+#define TIMER_REG_TMRSTAT 0x00
+#define TIMER_REG_TMR0LOAD 0x10
+#define TIMER_REG_TMR0CTL 0x18
+
+#define TMRSTAT_TMR0INT BIT(0)
+
+#define TMR0CTL_ENABLE BIT(7)
+#define TMR0CTL_MODE_PERIODIC BIT(4)
+#define TMR0CTL_PRESCALER 1
+#define TMR0CTL_PRESCALE_VAL (0xf - TMR0CTL_PRESCALER)
+#define TMR0CTL_PRESCALE_DIV (65536 / BIT(TMR0CTL_PRESCALER))
+
+struct rt_timer {
+ struct device *dev;
+ void __iomem *membase;
+ int irq;
+ unsigned long timer_freq;
+ unsigned long timer_div;
+};
+
+static inline void rt_timer_w32(struct rt_timer *rt, u8 reg, u32 val)
+{
+ __raw_writel(val, rt->membase + reg);
+}
+
+static inline u32 rt_timer_r32(struct rt_timer *rt, u8 reg)
+{
+ return __raw_readl(rt->membase + reg);
+}
+
+static irqreturn_t rt_timer_irq(int irq, void *_rt)
+{
+ struct rt_timer *rt = (struct rt_timer *) _rt;
+
+ rt_timer_w32(rt, TIMER_REG_TMR0LOAD, rt->timer_freq / rt->timer_div);
+ rt_timer_w32(rt, TIMER_REG_TMRSTAT, TMRSTAT_TMR0INT);
+
+ return IRQ_HANDLED;
+}
+
+
+static int rt_timer_request(struct rt_timer *rt)
+{
+ int err = request_irq(rt->irq, rt_timer_irq, IRQF_DISABLED,
+ dev_name(rt->dev), rt);
+ if (err) {
+ dev_err(rt->dev, "failed to request irq\n");
+ } else {
+ u32 t = TMR0CTL_MODE_PERIODIC | TMR0CTL_PRESCALE_VAL;
+ rt_timer_w32(rt, TIMER_REG_TMR0CTL, t);
+ }
+ return err;
+}
+
+static void rt_timer_free(struct rt_timer *rt)
+{
+ free_irq(rt->irq, rt);
+}
+
+static int rt_timer_config(struct rt_timer *rt, unsigned long divisor)
+{
+ if (rt->timer_freq < divisor)
+ rt->timer_div = rt->timer_freq;
+ else
+ rt->timer_div = divisor;
+
+ rt_timer_w32(rt, TIMER_REG_TMR0LOAD, rt->timer_freq / rt->timer_div);
+
+ return 0;
+}
+
+static int rt_timer_enable(struct rt_timer *rt)
+{
+ u32 t;
+
+ rt_timer_w32(rt, TIMER_REG_TMR0LOAD, rt->timer_freq / rt->timer_div);
+
+ t = rt_timer_r32(rt, TIMER_REG_TMR0CTL);
+ t |= TMR0CTL_ENABLE;
+ rt_timer_w32(rt, TIMER_REG_TMR0CTL, t);
+
+ return 0;
+}
+
+static void rt_timer_disable(struct rt_timer *rt)
+{
+ u32 t;
+
+ t = rt_timer_r32(rt, TIMER_REG_TMR0CTL);
+ t &= ~TMR0CTL_ENABLE;
+ rt_timer_w32(rt, TIMER_REG_TMR0CTL, t);
+}
+
+static int rt_timer_probe(struct platform_device *pdev)
+{
+ struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ struct rt_timer *rt;
+ struct clk *clk;
+
+ rt = devm_kzalloc(&pdev->dev, sizeof(*rt), GFP_KERNEL);
+ if (!rt) {
+ dev_err(&pdev->dev, "failed to allocate memory\n");
+ return -ENOMEM;
+ }
+
+ rt->irq = platform_get_irq(pdev, 0);
+ if (!rt->irq) {
+ dev_err(&pdev->dev, "failed to load irq\n");
+ return -ENOENT;
+ }
+
+ rt->membase = devm_request_and_ioremap(&pdev->dev, res);
+ if (IS_ERR(rt->membase))
+ return PTR_ERR(rt->membase);
+
+ clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(clk)) {
+ dev_err(&pdev->dev, "failed get clock rate\n");
+ return PTR_ERR(clk);
+ }
+
+ rt->timer_freq = clk_get_rate(clk) / TMR0CTL_PRESCALE_DIV;
+ if (!rt->timer_freq)
+ return -EINVAL;
+
+ rt->dev = &pdev->dev;
+ platform_set_drvdata(pdev, rt);
+
+ rt_timer_request(rt);
+ rt_timer_config(rt, 2);
+ rt_timer_enable(rt);
+
+ dev_info(&pdev->dev, "maximum frequncy is %luHz\n", rt->timer_freq);
+
+ return 0;
+}
+
+static int rt_timer_remove(struct platform_device *pdev)
+{
+ struct rt_timer *rt = platform_get_drvdata(pdev);
+
+ rt_timer_disable(rt);
+ rt_timer_free(rt);
+
+ return 0;
+}
+
+static const struct of_device_id rt_timer_match[] = {
+ { .compatible = "ralink,rt2880-timer" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, rt_timer_match);
+
+static struct platform_driver rt_timer_driver = {
+ .probe = rt_timer_probe,
+ .remove = rt_timer_remove,
+ .driver = {
+ .name = "rt-timer",
+ .owner = THIS_MODULE,
+ .of_match_table = rt_timer_match
+ },
+};
+
+module_platform_driver(rt_timer_driver);
+
+MODULE_DESCRIPTION("Ralink RT2880 timer");
+MODULE_AUTHOR("John Crispin <blogic@openwrt.org");
+MODULE_LICENSE("GPL");