diff options
author | Tony Lindgren <tony@atomide.com> | 2005-07-10 19:58:09 +0100 |
---|---|---|
committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2005-07-10 19:58:09 +0100 |
commit | 3b59b6beb423267e8fe2ef3596d98aba0b910341 (patch) | |
tree | 585d06163371608f1192e1d104da06290f1c5bd9 /arch/arm/mach-omap1 | |
parent | b288f75ffa6f26f720d0c69fcd09b4ee7122e17b (diff) | |
download | linux-3b59b6beb423267e8fe2ef3596d98aba0b910341.tar.gz linux-3b59b6beb423267e8fe2ef3596d98aba0b910341.tar.bz2 linux-3b59b6beb423267e8fe2ef3596d98aba0b910341.zip |
[PATCH] ARM: 2800/1: OMAP update 3/11: Move OMAP1 core code into mach-omap1 directory
Patch from Tony Lindgren
This patch by Paul Mundt and other OMAP developers
moves OMAP1 specific IRQ, time, and FPGA code into
mach-omap1 directory.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/mach-omap1')
-rw-r--r-- | arch/arm/mach-omap1/fpga.c | 188 | ||||
-rw-r--r-- | arch/arm/mach-omap1/irq.c | 234 | ||||
-rw-r--r-- | arch/arm/mach-omap1/time.c | 436 |
3 files changed, 858 insertions, 0 deletions
diff --git a/arch/arm/mach-omap1/fpga.c b/arch/arm/mach-omap1/fpga.c new file mode 100644 index 000000000000..7c08f6c2e1d0 --- /dev/null +++ b/arch/arm/mach-omap1/fpga.c @@ -0,0 +1,188 @@ +/* + * linux/arch/arm/mach-omap/fpga.c + * + * Interrupt handler for OMAP-1510 Innovator FPGA + * + * Copyright (C) 2001 RidgeRun, Inc. + * Author: Greg Lonnon <glonnon@ridgerun.com> + * + * Copyright (C) 2002 MontaVista Software, Inc. + * + * Separated FPGA interrupts from innovator1510.c and cleaned up for 2.6 + * Copyright (C) 2004 Nokia Corporation by Tony Lindrgen <tony@atomide.com> + * + * 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. + */ + +#include <linux/config.h> +#include <linux/types.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/device.h> +#include <linux/errno.h> + +#include <asm/hardware.h> +#include <asm/io.h> +#include <asm/irq.h> +#include <asm/mach/irq.h> + +#include <asm/arch/fpga.h> +#include <asm/arch/gpio.h> + +static void fpga_mask_irq(unsigned int irq) +{ + irq -= OMAP1510_IH_FPGA_BASE; + + if (irq < 8) + __raw_writeb((__raw_readb(OMAP1510_FPGA_IMR_LO) + & ~(1 << irq)), OMAP1510_FPGA_IMR_LO); + else if (irq < 16) + __raw_writeb((__raw_readb(OMAP1510_FPGA_IMR_HI) + & ~(1 << (irq - 8))), OMAP1510_FPGA_IMR_HI); + else + __raw_writeb((__raw_readb(INNOVATOR_FPGA_IMR2) + & ~(1 << (irq - 16))), INNOVATOR_FPGA_IMR2); +} + + +static inline u32 get_fpga_unmasked_irqs(void) +{ + return + ((__raw_readb(OMAP1510_FPGA_ISR_LO) & + __raw_readb(OMAP1510_FPGA_IMR_LO))) | + ((__raw_readb(OMAP1510_FPGA_ISR_HI) & + __raw_readb(OMAP1510_FPGA_IMR_HI)) << 8) | + ((__raw_readb(INNOVATOR_FPGA_ISR2) & + __raw_readb(INNOVATOR_FPGA_IMR2)) << 16); +} + + +static void fpga_ack_irq(unsigned int irq) +{ + /* Don't need to explicitly ACK FPGA interrupts */ +} + +static void fpga_unmask_irq(unsigned int irq) +{ + irq -= OMAP1510_IH_FPGA_BASE; + + if (irq < 8) + __raw_writeb((__raw_readb(OMAP1510_FPGA_IMR_LO) | (1 << irq)), + OMAP1510_FPGA_IMR_LO); + else if (irq < 16) + __raw_writeb((__raw_readb(OMAP1510_FPGA_IMR_HI) + | (1 << (irq - 8))), OMAP1510_FPGA_IMR_HI); + else + __raw_writeb((__raw_readb(INNOVATOR_FPGA_IMR2) + | (1 << (irq - 16))), INNOVATOR_FPGA_IMR2); +} + +static void fpga_mask_ack_irq(unsigned int irq) +{ + fpga_mask_irq(irq); + fpga_ack_irq(irq); +} + +void innovator_fpga_IRQ_demux(unsigned int irq, struct irqdesc *desc, + struct pt_regs *regs) +{ + struct irqdesc *d; + u32 stat; + int fpga_irq; + + stat = get_fpga_unmasked_irqs(); + + if (!stat) + return; + + for (fpga_irq = OMAP1510_IH_FPGA_BASE; + (fpga_irq < (OMAP1510_IH_FPGA_BASE + NR_FPGA_IRQS)) && stat; + fpga_irq++, stat >>= 1) { + if (stat & 1) { + d = irq_desc + fpga_irq; + d->handle(fpga_irq, d, regs); + } + } +} + +static struct irqchip omap_fpga_irq_ack = { + .ack = fpga_mask_ack_irq, + .mask = fpga_mask_irq, + .unmask = fpga_unmask_irq, +}; + + +static struct irqchip omap_fpga_irq = { + .ack = fpga_ack_irq, + .mask = fpga_mask_irq, + .unmask = fpga_unmask_irq, +}; + +/* + * All of the FPGA interrupt request inputs except for the touchscreen are + * edge-sensitive; the touchscreen is level-sensitive. The edge-sensitive + * interrupts are acknowledged as a side-effect of reading the interrupt + * status register from the FPGA. The edge-sensitive interrupt inputs + * cause a problem with level interrupt requests, such as Ethernet. The + * problem occurs when a level interrupt request is asserted while its + * interrupt input is masked in the FPGA, which results in a missed + * interrupt. + * + * In an attempt to workaround the problem with missed interrupts, the + * mask_ack routine for all of the FPGA interrupts has been changed from + * fpga_mask_ack_irq() to fpga_ack_irq() so that the specific FPGA interrupt + * being serviced is left unmasked. We can do this because the FPGA cascade + * interrupt is installed with the SA_INTERRUPT flag, which leaves all + * interrupts masked at the CPU while an FPGA interrupt handler executes. + * + * Limited testing indicates that this workaround appears to be effective + * for the smc9194 Ethernet driver used on the Innovator. It should work + * on other FPGA interrupts as well, but any drivers that explicitly mask + * interrupts at the interrupt controller via disable_irq/enable_irq + * could pose a problem. + */ +void omap1510_fpga_init_irq(void) +{ + int i; + + __raw_writeb(0, OMAP1510_FPGA_IMR_LO); + __raw_writeb(0, OMAP1510_FPGA_IMR_HI); + __raw_writeb(0, INNOVATOR_FPGA_IMR2); + + for (i = OMAP1510_IH_FPGA_BASE; i < (OMAP1510_IH_FPGA_BASE + NR_FPGA_IRQS); i++) { + + if (i == OMAP1510_INT_FPGA_TS) { + /* + * The touchscreen interrupt is level-sensitive, so + * we'll use the regular mask_ack routine for it. + */ + set_irq_chip(i, &omap_fpga_irq_ack); + } + else { + /* + * All FPGA interrupts except the touchscreen are + * edge-sensitive, so we won't mask them. + */ + set_irq_chip(i, &omap_fpga_irq); + } + + set_irq_handler(i, do_edge_IRQ); + set_irq_flags(i, IRQF_VALID); + } + + /* + * The FPGA interrupt line is connected to GPIO13. Claim this pin for + * the ARM. + * + * NOTE: For general GPIO/MPUIO access and interrupts, please see + * gpio.[ch] + */ + omap_request_gpio(13); + omap_set_gpio_direction(13, 1); + omap_set_gpio_edge_ctrl(13, OMAP_GPIO_RISING_EDGE); + set_irq_chained_handler(OMAP1510_INT_FPGA, innovator_fpga_IRQ_demux); +} + +EXPORT_SYMBOL(omap1510_fpga_init_irq); diff --git a/arch/arm/mach-omap1/irq.c b/arch/arm/mach-omap1/irq.c new file mode 100644 index 000000000000..a11b6d807352 --- /dev/null +++ b/arch/arm/mach-omap1/irq.c @@ -0,0 +1,234 @@ +/* + * linux/arch/arm/mach-omap/irq.c + * + * Interrupt handler for all OMAP boards + * + * Copyright (C) 2004 Nokia Corporation + * Written by Tony Lindgren <tony@atomide.com> + * Major cleanups by Juha Yrjölä <juha.yrjola@nokia.com> + * + * Completely re-written to support various OMAP chips with bank specific + * interrupt handlers. + * + * Some snippets of the code taken from the older OMAP interrupt handler + * Copyright (C) 2001 RidgeRun, Inc. Greg Lonnon <glonnon@ridgerun.com> + * + * GPIO interrupt handler moved to gpio.c by Juha Yrjola + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + * + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN + * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF + * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON + * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#include <linux/config.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/sched.h> +#include <linux/interrupt.h> +#include <linux/ptrace.h> + +#include <asm/hardware.h> +#include <asm/irq.h> +#include <asm/mach/irq.h> +#include <asm/arch/gpio.h> + +#include <asm/io.h> + +#define IRQ_BANK(irq) ((irq) >> 5) +#define IRQ_BIT(irq) ((irq) & 0x1f) + +struct omap_irq_bank { + unsigned long base_reg; + unsigned long trigger_map; + unsigned long wake_enable; +}; + +static unsigned int irq_bank_count = 0; +static struct omap_irq_bank *irq_banks; + +static inline unsigned int irq_bank_readl(int bank, int offset) +{ + return omap_readl(irq_banks[bank].base_reg + offset); +} + +static inline void irq_bank_writel(unsigned long value, int bank, int offset) +{ + omap_writel(value, irq_banks[bank].base_reg + offset); +} + +static void omap_ack_irq(unsigned int irq) +{ + if (irq > 31) + omap_writel(0x1, OMAP_IH2_BASE + IRQ_CONTROL_REG_OFFSET); + + omap_writel(0x1, OMAP_IH1_BASE + IRQ_CONTROL_REG_OFFSET); +} + +static void omap_mask_irq(unsigned int irq) +{ + int bank = IRQ_BANK(irq); + u32 l; + + l = omap_readl(irq_banks[bank].base_reg + IRQ_MIR_REG_OFFSET); + l |= 1 << IRQ_BIT(irq); + omap_writel(l, irq_banks[bank].base_reg + IRQ_MIR_REG_OFFSET); +} + +static void omap_unmask_irq(unsigned int irq) +{ + int bank = IRQ_BANK(irq); + u32 l; + + l = omap_readl(irq_banks[bank].base_reg + IRQ_MIR_REG_OFFSET); + l &= ~(1 << IRQ_BIT(irq)); + omap_writel(l, irq_banks[bank].base_reg + IRQ_MIR_REG_OFFSET); +} + +static void omap_mask_ack_irq(unsigned int irq) +{ + omap_mask_irq(irq); + omap_ack_irq(irq); +} + +static int omap_wake_irq(unsigned int irq, unsigned int enable) +{ + int bank = IRQ_BANK(irq); + + if (enable) + irq_banks[bank].wake_enable |= IRQ_BIT(irq); + else + irq_banks[bank].wake_enable &= ~IRQ_BIT(irq); + + return 0; +} + + +/* + * Allows tuning the IRQ type and priority + * + * NOTE: There is currently no OMAP fiq handler for Linux. Read the + * mailing list threads on FIQ handlers if you are planning to + * add a FIQ handler for OMAP. + */ +static void omap_irq_set_cfg(int irq, int fiq, int priority, int trigger) +{ + signed int bank; + unsigned long val, offset; + + bank = IRQ_BANK(irq); + /* FIQ is only available on bank 0 interrupts */ + fiq = bank ? 0 : (fiq & 0x1); + val = fiq | ((priority & 0x1f) << 2) | ((trigger & 0x1) << 1); + offset = IRQ_ILR0_REG_OFFSET + IRQ_BIT(irq) * 0x4; + irq_bank_writel(val, bank, offset); +} + +#ifdef CONFIG_ARCH_OMAP730 +static struct omap_irq_bank omap730_irq_banks[] = { + { .base_reg = OMAP_IH1_BASE, .trigger_map = 0xb3f8e22f }, + { .base_reg = OMAP_IH2_BASE, .trigger_map = 0xfdb9c1f2 }, + { .base_reg = OMAP_IH2_BASE + 0x100, .trigger_map = 0x800040f3 }, +}; +#endif + +#ifdef CONFIG_ARCH_OMAP1510 +static struct omap_irq_bank omap1510_irq_banks[] = { + { .base_reg = OMAP_IH1_BASE, .trigger_map = 0xb3febfff }, + { .base_reg = OMAP_IH2_BASE, .trigger_map = 0xffbfffed }, +}; +#endif + +#if defined(CONFIG_ARCH_OMAP16XX) + +static struct omap_irq_bank omap1610_irq_banks[] = { + { .base_reg = OMAP_IH1_BASE, .trigger_map = 0xb3fefe8f }, + { .base_reg = OMAP_IH2_BASE, .trigger_map = 0xfdb7c1fd }, + { .base_reg = OMAP_IH2_BASE + 0x100, .trigger_map = 0xffffb7ff }, + { .base_reg = OMAP_IH2_BASE + 0x200, .trigger_map = 0xffffffff }, +}; +#endif + +static struct irqchip omap_irq_chip = { + .ack = omap_mask_ack_irq, + .mask = omap_mask_irq, + .unmask = omap_unmask_irq, + .wake = omap_wake_irq, +}; + +void __init omap_init_irq(void) +{ + int i, j; + +#ifdef CONFIG_ARCH_OMAP730 + if (cpu_is_omap730()) { + irq_banks = omap730_irq_banks; + irq_bank_count = ARRAY_SIZE(omap730_irq_banks); + } +#endif +#ifdef CONFIG_ARCH_OMAP1510 + if (cpu_is_omap1510()) { + irq_banks = omap1510_irq_banks; + irq_bank_count = ARRAY_SIZE(omap1510_irq_banks); + } +#endif +#if defined(CONFIG_ARCH_OMAP16XX) + if (cpu_is_omap16xx()) { + irq_banks = omap1610_irq_banks; + irq_bank_count = ARRAY_SIZE(omap1610_irq_banks); + } +#endif + printk("Total of %i interrupts in %i interrupt banks\n", + irq_bank_count * 32, irq_bank_count); + + /* Mask and clear all interrupts */ + for (i = 0; i < irq_bank_count; i++) { + irq_bank_writel(~0x0, i, IRQ_MIR_REG_OFFSET); + irq_bank_writel(0x0, i, IRQ_ITR_REG_OFFSET); + } + + /* Clear any pending interrupts */ + irq_bank_writel(0x03, 0, IRQ_CONTROL_REG_OFFSET); + irq_bank_writel(0x03, 1, IRQ_CONTROL_REG_OFFSET); + + /* Enable interrupts in global mask */ + if (cpu_is_omap730()) { + irq_bank_writel(0x0, 0, IRQ_GMR_REG_OFFSET); + } + + /* Install the interrupt handlers for each bank */ + for (i = 0; i < irq_bank_count; i++) { + for (j = i * 32; j < (i + 1) * 32; j++) { + int irq_trigger; + + irq_trigger = irq_banks[i].trigger_map >> IRQ_BIT(j); + omap_irq_set_cfg(j, 0, 0, irq_trigger); + + set_irq_chip(j, &omap_irq_chip); + set_irq_handler(j, do_level_IRQ); + set_irq_flags(j, IRQF_VALID); + } + } + + /* Unmask level 2 handler */ + if (cpu_is_omap730()) { + omap_unmask_irq(INT_730_IH2_IRQ); + } else { + omap_unmask_irq(INT_IH2_IRQ); + } +} diff --git a/arch/arm/mach-omap1/time.c b/arch/arm/mach-omap1/time.c new file mode 100644 index 000000000000..d540539c9bbb --- /dev/null +++ b/arch/arm/mach-omap1/time.c @@ -0,0 +1,436 @@ +/* + * linux/arch/arm/mach-omap1/time.c + * + * OMAP Timers + * + * Copyright (C) 2004 Nokia Corporation + * Partial timer rewrite and additional dynamic tick timer support by + * Tony Lindgen <tony@atomide.com> and + * Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com> + * + * MPU timer code based on the older MPU timer code for OMAP + * Copyright (C) 2000 RidgeRun, Inc. + * Author: Greg Lonnon <glonnon@ridgerun.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + * + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN + * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF + * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON + * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#include <linux/config.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/delay.h> +#include <linux/interrupt.h> +#include <linux/sched.h> +#include <linux/spinlock.h> + +#include <asm/system.h> +#include <asm/hardware.h> +#include <asm/io.h> +#include <asm/leds.h> +#include <asm/irq.h> +#include <asm/mach/irq.h> +#include <asm/mach/time.h> + +struct sys_timer omap_timer; + +#ifdef CONFIG_OMAP_MPU_TIMER + +/* + * --------------------------------------------------------------------------- + * MPU timer + * --------------------------------------------------------------------------- + */ +#define OMAP_MPU_TIMER_BASE OMAP_MPU_TIMER1_BASE +#define OMAP_MPU_TIMER_OFFSET 0x100 + +/* cycles to nsec conversions taken from arch/i386/kernel/timers/timer_tsc.c, + * converted to use kHz by Kevin Hilman */ +/* convert from cycles(64bits) => nanoseconds (64bits) + * basic equation: + * ns = cycles / (freq / ns_per_sec) + * ns = cycles * (ns_per_sec / freq) + * ns = cycles * (10^9 / (cpu_khz * 10^3)) + * ns = cycles * (10^6 / cpu_khz) + * + * Then we use scaling math (suggested by george at mvista.com) to get: + * ns = cycles * (10^6 * SC / cpu_khz / SC + * ns = cycles * cyc2ns_scale / SC + * + * And since SC is a constant power of two, we can convert the div + * into a shift. + * -johnstul at us.ibm.com "math is hard, lets go shopping!" + */ +static unsigned long cyc2ns_scale; +#define CYC2NS_SCALE_FACTOR 10 /* 2^10, carefully chosen */ + +static inline void set_cyc2ns_scale(unsigned long cpu_khz) +{ + cyc2ns_scale = (1000000 << CYC2NS_SCALE_FACTOR)/cpu_khz; +} + +static inline unsigned long long cycles_2_ns(unsigned long long cyc) +{ + return (cyc * cyc2ns_scale) >> CYC2NS_SCALE_FACTOR; +} + +/* + * MPU_TICKS_PER_SEC must be an even number, otherwise machinecycles_to_usecs + * will break. On P2, the timer count rate is 6.5 MHz after programming PTV + * with 0. This divides the 13MHz input by 2, and is undocumented. + */ +#ifdef CONFIG_MACH_OMAP_PERSEUS2 +/* REVISIT: This ifdef construct should be replaced by a query to clock + * framework to see if timer base frequency is 12.0, 13.0 or 19.2 MHz. + */ +#define MPU_TICKS_PER_SEC (13000000 / 2) +#else +#define MPU_TICKS_PER_SEC (12000000 / 2) +#endif + +#define MPU_TIMER_TICK_PERIOD ((MPU_TICKS_PER_SEC / HZ) - 1) + +typedef struct { + u32 cntl; /* CNTL_TIMER, R/W */ + u32 load_tim; /* LOAD_TIM, W */ + u32 read_tim; /* READ_TIM, R */ +} omap_mpu_timer_regs_t; + +#define omap_mpu_timer_base(n) \ +((volatile omap_mpu_timer_regs_t*)IO_ADDRESS(OMAP_MPU_TIMER_BASE + \ + (n)*OMAP_MPU_TIMER_OFFSET)) + +static inline unsigned long omap_mpu_timer_read(int nr) +{ + volatile omap_mpu_timer_regs_t* timer = omap_mpu_timer_base(nr); + return timer->read_tim; +} + +static inline void omap_mpu_timer_start(int nr, unsigned long load_val) +{ + volatile omap_mpu_timer_regs_t* timer = omap_mpu_timer_base(nr); + + timer->cntl = MPU_TIMER_CLOCK_ENABLE; + udelay(1); + timer->load_tim = load_val; + udelay(1); + timer->cntl = (MPU_TIMER_CLOCK_ENABLE | MPU_TIMER_AR | MPU_TIMER_ST); +} + +unsigned long omap_mpu_timer_ticks_to_usecs(unsigned long nr_ticks) +{ + unsigned long long nsec; + + nsec = cycles_2_ns((unsigned long long)nr_ticks); + return (unsigned long)nsec / 1000; +} + +/* + * Last processed system timer interrupt + */ +static unsigned long omap_mpu_timer_last = 0; + +/* + * Returns elapsed usecs since last system timer interrupt + */ +static unsigned long omap_mpu_timer_gettimeoffset(void) +{ + unsigned long now = 0 - omap_mpu_timer_read(0); + unsigned long elapsed = now - omap_mpu_timer_last; + + return omap_mpu_timer_ticks_to_usecs(elapsed); +} + +/* + * Elapsed time between interrupts is calculated using timer0. + * Latency during the interrupt is calculated using timer1. + * Both timer0 and timer1 are counting at 6MHz (P2 6.5MHz). + */ +static irqreturn_t omap_mpu_timer_interrupt(int irq, void *dev_id, + struct pt_regs *regs) +{ + unsigned long now, latency; + + write_seqlock(&xtime_lock); + now = 0 - omap_mpu_timer_read(0); + latency = MPU_TICKS_PER_SEC / HZ - omap_mpu_timer_read(1); + omap_mpu_timer_last = now - latency; + timer_tick(regs); + write_sequnlock(&xtime_lock); + + return IRQ_HANDLED; +} + +static struct irqaction omap_mpu_timer_irq = { + .name = "mpu timer", + .flags = SA_INTERRUPT | SA_TIMER, + .handler = omap_mpu_timer_interrupt, +}; + +static unsigned long omap_mpu_timer1_overflows; +static irqreturn_t omap_mpu_timer1_interrupt(int irq, void *dev_id, + struct pt_regs *regs) +{ + omap_mpu_timer1_overflows++; + return IRQ_HANDLED; +} + +static struct irqaction omap_mpu_timer1_irq = { + .name = "mpu timer1 overflow", + .flags = SA_INTERRUPT, + .handler = omap_mpu_timer1_interrupt, +}; + +static __init void omap_init_mpu_timer(void) +{ + set_cyc2ns_scale(MPU_TICKS_PER_SEC / 1000); + omap_timer.offset = omap_mpu_timer_gettimeoffset; + setup_irq(INT_TIMER1, &omap_mpu_timer1_irq); + setup_irq(INT_TIMER2, &omap_mpu_timer_irq); + omap_mpu_timer_start(0, 0xffffffff); + omap_mpu_timer_start(1, MPU_TIMER_TICK_PERIOD); +} + +/* + * Scheduler clock - returns current time in nanosec units. + */ +unsigned long long sched_clock(void) +{ + unsigned long ticks = 0 - omap_mpu_timer_read(0); + unsigned long long ticks64; + + ticks64 = omap_mpu_timer1_overflows; + ticks64 <<= 32; + ticks64 |= ticks; + + return cycles_2_ns(ticks64); +} +#endif /* CONFIG_OMAP_MPU_TIMER */ + +#ifdef CONFIG_OMAP_32K_TIMER + +#ifdef CONFIG_ARCH_OMAP1510 +#error OMAP 32KHz timer does not currently work on 1510! +#endif + +/* + * --------------------------------------------------------------------------- + * 32KHz OS timer + * + * This currently works only on 16xx, as 1510 does not have the continuous + * 32KHz synchronous timer. The 32KHz synchronous timer is used to keep track + * of time in addition to the 32KHz OS timer. Using only the 32KHz OS timer + * on 1510 would be possible, but the timer would not be as accurate as + * with the 32KHz synchronized timer. + * --------------------------------------------------------------------------- + */ +#define OMAP_32K_TIMER_BASE 0xfffb9000 +#define OMAP_32K_TIMER_CR 0x08 +#define OMAP_32K_TIMER_TVR 0x00 +#define OMAP_32K_TIMER_TCR 0x04 + +#define OMAP_32K_TICKS_PER_HZ (32768 / HZ) +#if (32768 % HZ) != 0 +/* We cannot ignore modulo. + * Potential error can be as high as several percent. + */ +#define OMAP_32K_TICK_MODULO (32768 % HZ) +static unsigned modulo_count = 0; /* Counts 1/HZ units */ +#endif + +/* + * TRM says 1 / HZ = ( TVR + 1) / 32768, so TRV = (32768 / HZ) - 1 + * so with HZ = 100, TVR = 327.68. + */ +#define OMAP_32K_TIMER_TICK_PERIOD ((32768 / HZ) - 1) +#define TIMER_32K_SYNCHRONIZED 0xfffbc410 + +#define JIFFIES_TO_HW_TICKS(nr_jiffies, clock_rate) \ + (((nr_jiffies) * (clock_rate)) / HZ) + +static inline void omap_32k_timer_write(int val, int reg) +{ + omap_writew(val, reg + OMAP_32K_TIMER_BASE); +} + +static inline unsigned long omap_32k_timer_read(int reg) +{ + return omap_readl(reg + OMAP_32K_TIMER_BASE) & 0xffffff; +} + +/* + * The 32KHz synchronized timer is an additional timer on 16xx. + * It is always running. + */ +static inline unsigned long omap_32k_sync_timer_read(void) +{ + return omap_readl(TIMER_32K_SYNCHRONIZED); +} + +static inline void omap_32k_timer_start(unsigned long load_val) +{ + omap_32k_timer_write(load_val, OMAP_32K_TIMER_TVR); + omap_32k_timer_write(0x0f, OMAP_32K_TIMER_CR); +} + +static inline void omap_32k_timer_stop(void) +{ + omap_32k_timer_write(0x0, OMAP_32K_TIMER_CR); +} + +/* + * Rounds down to nearest usec + */ +static inline unsigned long omap_32k_ticks_to_usecs(unsigned long ticks_32k) +{ + return (ticks_32k * 5*5*5*5*5*5) >> 9; +} + +static unsigned long omap_32k_last_tick = 0; + +/* + * Returns elapsed usecs since last 32k timer interrupt + */ +static unsigned long omap_32k_timer_gettimeoffset(void) +{ + unsigned long now = omap_32k_sync_timer_read(); + return omap_32k_ticks_to_usecs(now - omap_32k_last_tick); +} + +/* + * Timer interrupt for 32KHz timer. When dynamic tick is enabled, this + * function is also called from other interrupts to remove latency + * issues with dynamic tick. In the dynamic tick case, we need to lock + * with irqsave. + */ +static irqreturn_t omap_32k_timer_interrupt(int irq, void *dev_id, + struct pt_regs *regs) +{ + unsigned long flags; + unsigned long now; + + write_seqlock_irqsave(&xtime_lock, flags); + now = omap_32k_sync_timer_read(); + + while (now - omap_32k_last_tick >= OMAP_32K_TICKS_PER_HZ) { +#ifdef OMAP_32K_TICK_MODULO + /* Modulo addition may put omap_32k_last_tick ahead of now + * and cause unwanted repetition of the while loop. + */ + if (unlikely(now - omap_32k_last_tick == ~0)) + break; + + modulo_count += OMAP_32K_TICK_MODULO; + if (modulo_count > HZ) { + ++omap_32k_last_tick; + modulo_count -= HZ; + } +#endif + omap_32k_last_tick += OMAP_32K_TICKS_PER_HZ; + timer_tick(regs); + } + + /* Restart timer so we don't drift off due to modulo or dynamic tick. + * By default we program the next timer to be continuous to avoid + * latencies during high system load. During dynamic tick operation the + * continuous timer can be overridden from pm_idle to be longer. + */ + omap_32k_timer_start(omap_32k_last_tick + OMAP_32K_TICKS_PER_HZ - now); + write_sequnlock_irqrestore(&xtime_lock, flags); + + return IRQ_HANDLED; +} + +#ifdef CONFIG_NO_IDLE_HZ +/* + * Programs the next timer interrupt needed. Called when dynamic tick is + * enabled, and to reprogram the ticks to skip from pm_idle. Note that + * we can keep the timer continuous, and don't need to set it to run in + * one-shot mode. This is because the timer will get reprogrammed again + * after next interrupt. + */ +void omap_32k_timer_reprogram(unsigned long next_tick) +{ + omap_32k_timer_start(JIFFIES_TO_HW_TICKS(next_tick, 32768) + 1); +} + +static struct irqaction omap_32k_timer_irq; +extern struct timer_update_handler timer_update; + +static int omap_32k_timer_enable_dyn_tick(void) +{ + /* No need to reprogram timer, just use the next interrupt */ + return 0; +} + +static int omap_32k_timer_disable_dyn_tick(void) +{ + omap_32k_timer_start(OMAP_32K_TIMER_TICK_PERIOD); + return 0; +} + +static struct dyn_tick_timer omap_dyn_tick_timer = { + .enable = omap_32k_timer_enable_dyn_tick, + .disable = omap_32k_timer_disable_dyn_tick, + .reprogram = omap_32k_timer_reprogram, + .handler = omap_32k_timer_interrupt, +}; +#endif /* CONFIG_NO_IDLE_HZ */ + +static struct irqaction omap_32k_timer_irq = { + .name = "32KHz timer", + .flags = SA_INTERRUPT | SA_TIMER, + .handler = omap_32k_timer_interrupt, +}; + +static __init void omap_init_32k_timer(void) +{ + +#ifdef CONFIG_NO_IDLE_HZ + omap_timer.dyn_tick = &omap_dyn_tick_timer; +#endif + + setup_irq(INT_OS_TIMER, &omap_32k_timer_irq); + omap_timer.offset = omap_32k_timer_gettimeoffset; + omap_32k_last_tick = omap_32k_sync_timer_read(); + omap_32k_timer_start(OMAP_32K_TIMER_TICK_PERIOD); +} +#endif /* CONFIG_OMAP_32K_TIMER */ + +/* + * --------------------------------------------------------------------------- + * Timer initialization + * --------------------------------------------------------------------------- + */ +static void __init omap_timer_init(void) +{ +#if defined(CONFIG_OMAP_MPU_TIMER) + omap_init_mpu_timer(); +#elif defined(CONFIG_OMAP_32K_TIMER) + omap_init_32k_timer(); +#else +#error No system timer selected in Kconfig! +#endif +} + +struct sys_timer omap_timer = { + .init = omap_timer_init, + .offset = NULL, /* Initialized later */ +}; |