Add a timer driver for the MPC83xx architecture.
Signed-off-by: Mario Six mario.six@gdsys.cc
---
v1 -> v2: * Removed now-superfluous comments * Removed usage of uclass_{first,next}_device_compat * Switched to usage of new board uclass (instead of devinfo)
--- arch/powerpc/cpu/mpc83xx/cpu.c | 4 +- arch/powerpc/lib/Makefile | 4 ++ arch/powerpc/lib/interrupts.c | 5 +- drivers/timer/Kconfig | 7 ++ drivers/timer/Makefile | 1 + drivers/timer/mpc83xx_timer.c | 160 +++++++++++++++++++++++++++++++++++++++++ 6 files changed, 178 insertions(+), 3 deletions(-) create mode 100644 drivers/timer/mpc83xx_timer.c
diff --git a/arch/powerpc/cpu/mpc83xx/cpu.c b/arch/powerpc/cpu/mpc83xx/cpu.c index 9a5c1b7d55..376483eda7 100644 --- a/arch/powerpc/cpu/mpc83xx/cpu.c +++ b/arch/powerpc/cpu/mpc83xx/cpu.c @@ -176,12 +176,12 @@ do_reset (cmd_tbl_t * cmdtp, int flag, int argc, char * const argv[]) /* * Get timebase clock frequency (like cpu_clk in Hz) */ - +#ifndef CONFIG_TIMER unsigned long get_tbclk(void) { return (gd->bus_clk + 3L) / 4L; } - +#endif
#if defined(CONFIG_WATCHDOG) void watchdog_reset (void) diff --git a/arch/powerpc/lib/Makefile b/arch/powerpc/lib/Makefile index 9a3043abf8..537693e3bc 100644 --- a/arch/powerpc/lib/Makefile +++ b/arch/powerpc/lib/Makefile @@ -19,13 +19,17 @@ endif
ifdef MINIMAL obj-y += cache.o time.o +ifndef CONFIG_TIMER obj-y += ticks.o +endif else
obj-y += ppcstring.o
obj-y += ppccache.o +ifndef CONFIG_TIMER obj-y += ticks.o +endif obj-y += reloc.o
obj-$(CONFIG_BAT_RW) += bat_rw.o diff --git a/arch/powerpc/lib/interrupts.c b/arch/powerpc/lib/interrupts.c index e8784aa16e..56a697d28c 100644 --- a/arch/powerpc/lib/interrupts.c +++ b/arch/powerpc/lib/interrupts.c @@ -15,6 +15,7 @@ #include <status_led.h> #endif
+#ifndef CONFIG_MPC83XX_TIMER #ifdef CONFIG_SHOW_ACTIVITY void board_show_activity (ulong) __attribute__((weak, alias("__board_show_activity")));
@@ -45,7 +46,7 @@ static __inline__ void set_dec (unsigned long val) if (val) asm volatile ("mtdec %0"::"r" (val)); } - +#endif /* !CONFIG_MPC83XX_TIMER */
void enable_interrupts (void) { @@ -61,6 +62,7 @@ int disable_interrupts (void) return ((msr & MSR_EE) != 0); }
+#ifndef CONFIG_MPC83XX_TIMER int interrupt_init (void) { /* call cpu specific function from $(CPU)/interrupts.c */ @@ -103,3 +105,4 @@ ulong get_timer (ulong base) { return (timestamp - base); } +#endif /* !CONFIG_MPC83XX_TIMER */ diff --git a/drivers/timer/Kconfig b/drivers/timer/Kconfig index 2c96896726..1b78ce784a 100644 --- a/drivers/timer/Kconfig +++ b/drivers/timer/Kconfig @@ -126,4 +126,11 @@ config STM32_TIMER Select this to enable support for the timer found on STM32 devices.
+config MPC83XX_TIMER + bool "MPC83xx timer support" + depends on TIMER + help + Select this to enable support for the timer found on + devices based on the MPC83xx family of SoCs. + endmenu diff --git a/drivers/timer/Makefile b/drivers/timer/Makefile index a6e7832154..d35d235195 100644 --- a/drivers/timer/Makefile +++ b/drivers/timer/Makefile @@ -17,3 +17,4 @@ obj-$(CONFIG_ATCPIT100_TIMER) += atcpit100_timer.o obj-$(CONFIG_ROCKCHIP_TIMER) += rockchip_timer.o obj-$(CONFIG_ATMEL_PIT_TIMER) += atmel_pit_timer.o obj-$(CONFIG_STM32_TIMER) += stm32_timer.o +obj-$(CONFIG_MPC83XX_TIMER) += mpc83xx_timer.o diff --git a/drivers/timer/mpc83xx_timer.c b/drivers/timer/mpc83xx_timer.c new file mode 100644 index 0000000000..c3dd306c5b --- /dev/null +++ b/drivers/timer/mpc83xx_timer.c @@ -0,0 +1,160 @@ +/* + * (C) Copyright 2018 + * Mario Six, Guntermann & Drunck GmbH, mario.six@gdsys.cc + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <dm.h> +#include <clk.h> +#include <timer.h> +#include <watchdog.h> +#include <board.h> + +struct mpc83xx_timer_priv { +}; + +static uint decrementer_count; /* count value for 1e6/HZ microseconds */ + +static inline unsigned long get_dec(void) +{ + unsigned long val; + + asm volatile ("mfdec %0":"=r" (val):); + + return val; +} + +static inline void set_dec(unsigned long val) +{ + if (val) + asm volatile ("mtdec %0"::"r" (val)); +} + +/* TODO(mario.six@gdsys.cc): This should really be done by timer_init, and the + * interrupt init should go into a interrupt driver. + */ +int interrupt_init(void) +{ + immap_t *immr = (immap_t *)CONFIG_SYS_IMMR; + struct udevice *csb; + struct udevice *board; + struct clk clock; + + if (get_board(&board)) + return -ENOENT; + + uclass_get_device_by_phandle(UCLASS_SIMPLE_BUS, board, "csb", &csb); + clk_get_by_index(csb, 0, &clock); + + decrementer_count = (clk_get_rate(&clock) / 4) / CONFIG_SYS_HZ; + + /* Enable e300 time base */ + + setbits_be32(&immr->sysconf.spcr, 0x00400000); + + set_dec(decrementer_count); + + set_msr(get_msr() | MSR_EE); + + return 0; +} + +static volatile ulong timestamp = 0; + +void timer_interrupt(struct pt_regs *regs) +{ + /* Restore Decrementer Count */ + set_dec(decrementer_count); + + timestamp++; + +#if defined(CONFIG_WATCHDOG) || defined(CONFIG_HW_WATCHDOG) + if ((timestamp % (CONFIG_SYS_WATCHDOG_FREQ)) == 0) + WATCHDOG_RESET(); +#endif /* CONFIG_WATCHDOG || CONFIG_HW_WATCHDOG */ + +#ifdef CONFIG_LED_STATUS + status_led_tick(timestamp); +#endif /* CONFIG_LED_STATUS */ + +#ifdef CONFIG_SHOW_ACTIVITY + board_show_activity(timestamp); +#endif /* CONFIG_SHOW_ACTIVITY */ +} + +ulong get_timer(ulong base) +{ + return (timestamp - base); +} + +static inline u32 mftbu(void) +{ + u32 rval; + + asm volatile("mftbu %0" : "=r" (rval)); + return rval; +} + +static inline u32 mftb(void) +{ + u32 rval; + + asm volatile("mftb %0" : "=r" (rval)); + return rval; +} + +void wait_ticks(ulong ticks) +{ + ulong end = get_ticks() + ticks; + + while (end > get_ticks()) + WATCHDOG_RESET(); +} + +static int mpc83xx_timer_get_count(struct udevice *dev, u64 *count) +{ + u32 tbu, tbl; + + do { + tbu = mftbu(); + tbl = mftb(); + } while (tbu != mftbu()); + + *count = (tbu * 0x10000ULL) + tbl; + + return 0; +} + +static int mpc83xx_timer_probe(struct udevice *dev) +{ + struct timer_dev_priv *uc_priv = dev->uclass_priv; + struct clk clock; + + interrupt_init(); + + clk_get_by_index(dev, 0, &clock); + + uc_priv->clock_rate = (clk_get_rate(&clock) + 3L) / 4L; + + return 0; +} + +static const struct timer_ops mpc83xx_timer_ops = { + .get_count = mpc83xx_timer_get_count, +}; + +static const struct udevice_id mpc83xx_timer_ids[] = { + { .compatible = "fsl,mpc83xx-timer" }, + { /* sentinel */ } +}; + +U_BOOT_DRIVER(mpc83xx_timer) = { + .name = "mpc83xx_timer", + .id = UCLASS_TIMER, + .of_match = mpc83xx_timer_ids, + .probe = mpc83xx_timer_probe, + .ops = &mpc83xx_timer_ops, + .flags = DM_FLAG_PRE_RELOC, +}; -- 2.16.1