Add a timer driver for the MPC83xx architecture.
Signed-off-by: Mario Six mario.six@gdsys.cc
---
v2 -> v3: * Got rid of the static variables * Added driver files to MAINTAINERS
v1 -> v2: * Removed now-superfluous comments * Removed usage of uclass_{first,next}_device_compat * Switched to usage of new board uclass (instead of devinfo)
--- MAINTAINERS | 1 + 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 | 182 +++++++++++++++++++++++++++++++++++++++++ 7 files changed, 201 insertions(+), 3 deletions(-) create mode 100644 drivers/timer/mpc83xx_timer.c
diff --git a/MAINTAINERS b/MAINTAINERS index ab0f6a0a5d0..f03cfcc73b0 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -474,6 +474,7 @@ F: drivers/sysreset/sysreset_mpc83xx.c F: drivers/clk/mpc83xx_clk.c F: drivers/clk/mpc83xx_clk.h F: include/dt-bindings/clk/mpc83xx-clk.h +F: drivers/timer/mpc83xx_timer.c F: arch/powerpc/cpu/mpc83xx/ F: arch/powerpc/include/asm/arch-mpc83xx/
diff --git a/arch/powerpc/cpu/mpc83xx/cpu.c b/arch/powerpc/cpu/mpc83xx/cpu.c index e1d2f2f07cb..ffb42415feb 100644 --- a/arch/powerpc/cpu/mpc83xx/cpu.c +++ b/arch/powerpc/cpu/mpc83xx/cpu.c @@ -175,12 +175,12 @@ 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 c3acefaea7e..8ac49bdd060 100644 --- a/arch/powerpc/lib/Makefile +++ b/arch/powerpc/lib/Makefile @@ -17,13 +17,17 @@ 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 f63e5cf799b..19682cfcfad 100644 --- a/arch/powerpc/lib/interrupts.c +++ b/arch/powerpc/lib/interrupts.c @@ -14,6 +14,7 @@ #include <status_led.h> #endif
+#ifndef CONFIG_MPC83XX_TIMER #ifdef CONFIG_SHOW_ACTIVITY void board_show_activity (ulong) __attribute__((weak, alias("__board_show_activity")));
@@ -44,7 +45,7 @@ static __inline__ void set_dec (unsigned long val) if (val) asm volatile ("mtdec %0"::"r" (val)); } - +#endif /* !CONFIG_MPC83XX_TIMER */
void enable_interrupts (void) { @@ -60,6 +61,7 @@ int disable_interrupts (void) return ((msr & MSR_EE) != 0); }
+#ifndef CONFIG_MPC83XX_TIMER int interrupt_init (void) { /* call cpu specific function from $(CPU)/interrupts.c */ @@ -102,3 +104,4 @@ ulong get_timer (ulong base) { return (timestamp - base); } +#endif /* !CONFIG_MPC83XX_TIMER */ diff --git a/drivers/timer/Kconfig b/drivers/timer/Kconfig index 8a31397553d..c7909bd6e52 100644 --- a/drivers/timer/Kconfig +++ b/drivers/timer/Kconfig @@ -133,4 +133,11 @@ config STM32_TIMER Select this to enable support for the timer found on STM32 devices.
+config MPC83XX_TIMER + bool "MPC83xx timer support" + depends on TIMER + help + Select this to enable support for the timer found on + devices based on the MPC83xx family of SoCs. + endmenu diff --git a/drivers/timer/Makefile b/drivers/timer/Makefile index ee2fcb1fa71..75360d81de3 100644 --- a/drivers/timer/Makefile +++ b/drivers/timer/Makefile @@ -16,3 +16,4 @@ obj-$(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 00000000000..148fb2550ca --- /dev/null +++ b/drivers/timer/mpc83xx_timer.c @@ -0,0 +1,182 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * (C) Copyright 2018 + * Mario Six, Guntermann & Drunck GmbH, mario.six@gdsys.cc + */ + +#include <common.h> +#include <dm.h> +#include <clk.h> +#include <timer.h> +#include <watchdog.h> +#include <board.h> + +DECLARE_GLOBAL_DATA_PTR; + +struct mpc83xx_timer_priv { + uint decrementer_count; /* count value for 1e6/HZ microseconds */ + ulong timestamp; +}; + +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 udevice *timer = gd->timer; + struct mpc83xx_timer_priv *timer_priv = dev_get_priv(timer); + struct clk clock; + int ret; + + if (get_board(&board)) { + debug("%s: board device could not be fetched.\n", __func__); + return -ENOENT; + } + + ret = uclass_get_device_by_phandle(UCLASS_SIMPLE_BUS, board, + "csb", &csb); + if (ret) { + debug("%s: Could not retrieve CSB device (error: %d)", + __func__, ret); + return ret; + } + + ret = clk_get_by_index(csb, 0, &clock); + if (ret) { + debug("%s: Could not retrieve clock (error: %d)", + __func__, ret); + return ret; + } + + timer_priv->decrementer_count = (clk_get_rate(&clock) / 4) + / CONFIG_SYS_HZ; + /* Enable e300 time base */ + setbits_be32(&immr->sysconf.spcr, 0x00400000); + + set_dec(timer_priv->decrementer_count); + + set_msr(get_msr() | MSR_EE); + + return 0; +} + +void timer_interrupt(struct pt_regs *regs) +{ + struct udevice *timer = gd->timer; + struct mpc83xx_timer_priv *priv = dev_get_priv(timer); + + /* Restore Decrementer Count */ + set_dec(priv->decrementer_count); + + priv->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(priv->timestamp); +#endif /* CONFIG_LED_STATUS */ + +#ifdef CONFIG_SHOW_ACTIVITY + board_show_activity(priv->timestamp); +#endif /* CONFIG_SHOW_ACTIVITY */ +} + +ulong get_timer(ulong base) +{ + struct udevice *timer = gd->timer; + struct mpc83xx_timer_priv *priv = dev_get_priv(timer); + + return (priv->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, + .priv_auto_alloc_size = sizeof(struct mpc83xx_timer_priv), +}; -- 2.11.0