From 4697abea62a3b02c9c346b94d7eae2e4a1c6cfd0 Mon Sep 17 00:00:00 2001 From: "maxims@google.com" Date: Wed, 18 Jan 2017 13:44:55 -0800 Subject: aspeed: Add drivers common to all Aspeed SoCs Add support for Watchdog Timer, which is compatible with AST2400 and AST2500 watchdogs. There is no uclass for Watchdog yet, so the driver does not follow the driver model. It also uses fixed clock, so no clock driver is needed. Add support for timer for Aspeed ast2400/ast2500 devices. The driver actually controls several devices, but because all devices share the same Control Register, it is somewhat difficult to completely decouple them. Since only one timer is needed at the moment, this should be OK. The timer uses fixed clock, so does not rely on a clock driver. Add sysreset driver, which uses watchdog timer to do resets and particular watchdog device to use is hardcoded (0) Reviewed-by: Simon Glass --- drivers/timer/Kconfig | 12 ++++++ drivers/timer/Makefile | 1 + drivers/timer/ast_timer.c | 97 +++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 110 insertions(+) create mode 100644 drivers/timer/ast_timer.c (limited to 'drivers/timer') diff --git a/drivers/timer/Kconfig b/drivers/timer/Kconfig index cb18f12fc9..cd38a6d4bd 100644 --- a/drivers/timer/Kconfig +++ b/drivers/timer/Kconfig @@ -46,4 +46,16 @@ config OMAP_TIMER help Select this to enable an timer for Omap devices. +config AST_TIMER + bool "Aspeed ast2400/ast2500 timer support" + depends on TIMER + default y if ARCH_ASPEED + help + Select this to enable timer for Aspeed ast2400/ast2500 devices. + This is a simple sys timer driver, it is compatible with lib/time.c, + but does not support any interrupts. Even though SoC has 8 hardware + counters, they are all treated as a single device by this driver. + This is mostly because they all share several registers which + makes it difficult to completely separate them. + endmenu diff --git a/drivers/timer/Makefile b/drivers/timer/Makefile index f351fbb4e0..a4b1a486b0 100644 --- a/drivers/timer/Makefile +++ b/drivers/timer/Makefile @@ -9,3 +9,4 @@ obj-$(CONFIG_ALTERA_TIMER) += altera_timer.o obj-$(CONFIG_SANDBOX_TIMER) += sandbox_timer.o obj-$(CONFIG_X86_TSC_TIMER) += tsc_timer.o obj-$(CONFIG_OMAP_TIMER) += omap-timer.o +obj-$(CONFIG_AST_TIMER) += ast_timer.o diff --git a/drivers/timer/ast_timer.c b/drivers/timer/ast_timer.c new file mode 100644 index 0000000000..d7c5460cd3 --- /dev/null +++ b/drivers/timer/ast_timer.c @@ -0,0 +1,97 @@ +/* + * Copyright 2016 Google Inc. + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include +#include +#include +#include +#include +#include + +DECLARE_GLOBAL_DATA_PTR; + +#define AST_TICK_TIMER 1 +#define AST_TMC_RELOAD_VAL 0xffffffff + +struct ast_timer_priv { + struct ast_timer *regs; + struct ast_timer_counter *tmc; +}; + +static struct ast_timer_counter *ast_get_timer_counter(struct ast_timer *timer, + int n) +{ + if (n > 3) + return &timer->timers2[n - 4]; + else + return &timer->timers1[n - 1]; +} + +static int ast_timer_probe(struct udevice *dev) +{ + struct ast_timer_priv *priv = dev_get_priv(dev); + struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev); + + writel(AST_TMC_RELOAD_VAL, &priv->tmc->reload_val); + + /* + * Stop the timer. This will also load reload_val into + * the status register. + */ + clrbits_le32(&priv->regs->ctrl1, + AST_TMC_EN << AST_TMC_CTRL1_SHIFT(AST_TICK_TIMER)); + /* Start the timer from the fixed 1MHz clock. */ + setbits_le32(&priv->regs->ctrl1, + (AST_TMC_EN | AST_TMC_1MHZ) << + AST_TMC_CTRL1_SHIFT(AST_TICK_TIMER)); + + uc_priv->clock_rate = AST_TMC_RATE; + + return 0; +} + +static int ast_timer_get_count(struct udevice *dev, u64 *count) +{ + struct ast_timer_priv *priv = dev_get_priv(dev); + + *count = AST_TMC_RELOAD_VAL - readl(&priv->tmc->status); + + return 0; +} + +static int ast_timer_ofdata_to_platdata(struct udevice *dev) +{ + struct ast_timer_priv *priv = dev_get_priv(dev); + + priv->regs = dev_get_addr_ptr(dev); + if (IS_ERR(priv->regs)) + return PTR_ERR(priv->regs); + + priv->tmc = ast_get_timer_counter(priv->regs, AST_TICK_TIMER); + + return 0; +} + +static const struct timer_ops ast_timer_ops = { + .get_count = ast_timer_get_count, +}; + +static const struct udevice_id ast_timer_ids[] = { + { .compatible = "aspeed,ast2500-timer" }, + { .compatible = "aspeed,ast2400-timer" }, + { } +}; + +U_BOOT_DRIVER(ast_timer) = { + .name = "ast_timer", + .id = UCLASS_TIMER, + .of_match = ast_timer_ids, + .probe = ast_timer_probe, + .priv_auto_alloc_size = sizeof(struct ast_timer_priv), + .ofdata_to_platdata = ast_timer_ofdata_to_platdata, + .ops = &ast_timer_ops, + .flags = DM_FLAG_PRE_RELOC, +}; -- cgit