diff --git a/drivers/timer/Kconfig b/drivers/timer/Kconfig index 6d6665005c..f32bd16227 100644 --- a/drivers/timer/Kconfig +++ b/drivers/timer/Kconfig @@ -252,6 +252,14 @@ config STM32_TIMER Select this to enable support for the timer found on STM32 devices. +config TEGRA_TIMER + bool "Tegra timer support" + depends on TIMER + select TIMER_EARLY + help + Select this to enable support for the timer found on + Tegra devices. + config X86_TSC_TIMER bool "x86 Time-Stamp Counter (TSC) timer support" depends on TIMER && X86 diff --git a/drivers/timer/Makefile b/drivers/timer/Makefile index 6470fd5426..3c92113fc6 100644 --- a/drivers/timer/Makefile +++ b/drivers/timer/Makefile @@ -27,6 +27,7 @@ obj-$(CONFIG_SP804_TIMER) += sp804_timer.o obj-$(CONFIG_$(SPL_)SIFIVE_CLINT) += sifive_clint_timer.o obj-$(CONFIG_ARM_GLOBAL_TIMER) += arm_global_timer.o obj-$(CONFIG_STM32_TIMER) += stm32_timer.o +obj-$(CONFIG_TEGRA_TIMER) += tegra-timer.o obj-$(CONFIG_X86_TSC_TIMER) += tsc_timer.o obj-$(CONFIG_MTK_TIMER) += mtk_timer.o obj-$(CONFIG_MCHP_PIT64B_TIMER) += mchp-pit64b-timer.o diff --git a/drivers/timer/tegra-timer.c b/drivers/timer/tegra-timer.c new file mode 100644 index 0000000000..a867c649c3 --- /dev/null +++ b/drivers/timer/tegra-timer.c @@ -0,0 +1,130 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2022 Svyatoslav Ryhel + */ + +#include +#include +#include +#include + +#include +#include +#include + +#define TEGRA_OSC_CLK_ENB_L_SET (NV_PA_CLK_RST_BASE + 0x320) +#define TEGRA_OSC_SET_CLK_ENB_TMR BIT(5) + +#define TEGRA_TIMER_USEC_CNTR (NV_PA_TMRUS_BASE + 0) +#define TEGRA_TIMER_USEC_CFG (NV_PA_TMRUS_BASE + 4) + +#define TEGRA_TIMER_RATE 1000000 /* 1 MHz */ + +/* + * On pre-DM stage timer should be left configured by + * previous bootloader for correct 1MHz clock. + * In the case of reset default value is set to 1/13 of + * CLK_M which should be decent enough to safely + * get to DM stage. + */ +u64 notrace timer_early_get_count(void) +{ + /* At this stage raw timer is used */ + return readl(TEGRA_TIMER_USEC_CNTR); +} + +unsigned long notrace timer_early_get_rate(void) +{ + return TEGRA_TIMER_RATE; +} + +ulong timer_get_boot_us(void) +{ + return timer_early_get_count(); +} + +/* + * At moment of calling get_count, timer driver is already + * probed and is configured to have precise 1MHz clock. + * Tegra timer has a step of 1 microsecond which removes + * need of using adjusments involving uc_priv->clock_rate. + */ +static notrace u64 tegra_timer_get_count(struct udevice *dev) +{ + u32 val = timer_early_get_count(); + return timer_conv_64(val); +} + +static int tegra_timer_probe(struct udevice *dev) +{ + struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev); + u32 usec_config, value; + + /* Timer rate has to be set unconditionally */ + uc_priv->clock_rate = TEGRA_TIMER_RATE; + + /* + * Configure microsecond timers to have 1MHz clock + * Config register is 0xqqww, where qq is "dividend", ww is "divisor" + * Uses n+1 scheme + */ + switch (clock_get_rate(CLOCK_ID_CLK_M)) { + case 12000000: + usec_config = 0x000b; /* (11+1)/(0+1) */ + break; + case 12800000: + usec_config = 0x043f; /* (63+1)/(4+1) */ + break; + case 13000000: + usec_config = 0x000c; /* (12+1)/(0+1) */ + break; + case 16800000: + usec_config = 0x0453; /* (83+1)/(4+1) */ + break; + case 19200000: + usec_config = 0x045f; /* (95+1)/(4+1) */ + break; + case 26000000: + usec_config = 0x0019; /* (25+1)/(0+1) */ + break; + case 38400000: + usec_config = 0x04bf; /* (191+1)/(4+1) */ + break; + case 48000000: + usec_config = 0x002f; /* (47+1)/(0+1) */ + break; + default: + return -EINVAL; + } + + /* Enable clock to timer hardware */ + value = readl_relaxed(TEGRA_OSC_CLK_ENB_L_SET); + writel_relaxed(value | TEGRA_OSC_SET_CLK_ENB_TMR, + TEGRA_OSC_CLK_ENB_L_SET); + + writel_relaxed(usec_config, TEGRA_TIMER_USEC_CFG); + + return 0; +} + +static const struct timer_ops tegra_timer_ops = { + .get_count = tegra_timer_get_count, +}; + +static const struct udevice_id tegra_timer_ids[] = { + { .compatible = "nvidia,tegra20-timer" }, + { .compatible = "nvidia,tegra30-timer" }, + { .compatible = "nvidia,tegra114-timer" }, + { .compatible = "nvidia,tegra124-timer" }, + { .compatible = "nvidia,tegra210-timer" }, + { } +}; + +U_BOOT_DRIVER(tegra_timer) = { + .name = "tegra_timer", + .id = UCLASS_TIMER, + .of_match = tegra_timer_ids, + .probe = tegra_timer_probe, + .ops = &tegra_timer_ops, + .flags = DM_FLAG_PRE_RELOC, +};