diff options
Diffstat (limited to 'plat/nvidia/tegra/drivers/pmc/pmc.c')
-rw-r--r-- | plat/nvidia/tegra/drivers/pmc/pmc.c | 153 |
1 files changed, 153 insertions, 0 deletions
diff --git a/plat/nvidia/tegra/drivers/pmc/pmc.c b/plat/nvidia/tegra/drivers/pmc/pmc.c new file mode 100644 index 0000000..e70e7a6 --- /dev/null +++ b/plat/nvidia/tegra/drivers/pmc/pmc.c @@ -0,0 +1,153 @@ +/* + * Copyright (c) 2015, ARM Limited and Contributors. All rights reserved. + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#include <assert.h> + +#include <arch_helpers.h> +#include <common/debug.h> +#include <lib/mmio.h> + +#include <pmc.h> +#include <tegra_def.h> + +#define RESET_ENABLE 0x10U + +/* Module IDs used during power ungate procedure */ +static const uint32_t pmc_cpu_powergate_id[4] = { + 14, /* CPU 0 */ + 9, /* CPU 1 */ + 10, /* CPU 2 */ + 11 /* CPU 3 */ +}; + +/******************************************************************************* + * Power ungate CPU to start the boot process. CPU reset vectors must be + * populated before calling this function. + ******************************************************************************/ +void tegra_pmc_cpu_on(int32_t cpu) +{ + uint32_t val; + + /* + * Check if CPU is already power ungated + */ + val = tegra_pmc_read_32(PMC_PWRGATE_STATUS); + if ((val & (1U << pmc_cpu_powergate_id[cpu])) == 0U) { + /* + * The PMC deasserts the START bit when it starts the power + * ungate process. Loop till no power toggle is in progress. + */ + do { + val = tegra_pmc_read_32(PMC_PWRGATE_TOGGLE); + } while ((val & PMC_TOGGLE_START) != 0U); + + /* + * Start the power ungate procedure + */ + val = pmc_cpu_powergate_id[cpu] | PMC_TOGGLE_START; + tegra_pmc_write_32(PMC_PWRGATE_TOGGLE, val); + + /* + * The PMC deasserts the START bit when it starts the power + * ungate process. Loop till powergate START bit is asserted. + */ + do { + val = tegra_pmc_read_32(PMC_PWRGATE_TOGGLE); + } while ((val & (1U << 8)) != 0U); + + /* loop till the CPU is power ungated */ + do { + val = tegra_pmc_read_32(PMC_PWRGATE_STATUS); + } while ((val & (1U << pmc_cpu_powergate_id[cpu])) == 0U); + } +} + +/******************************************************************************* + * Setup CPU vectors for resume from deep sleep + ******************************************************************************/ +void tegra_pmc_cpu_setup(uint64_t reset_addr) +{ + uint32_t val; + + tegra_pmc_write_32(PMC_SECURE_SCRATCH34, + ((uint32_t)reset_addr & 0xFFFFFFFFU) | 1U); + val = (uint32_t)(reset_addr >> 32U); + tegra_pmc_write_32(PMC_SECURE_SCRATCH35, val & 0x7FFU); +} + +/******************************************************************************* + * Lock CPU vectors to restrict further writes + ******************************************************************************/ +void tegra_pmc_lock_cpu_vectors(void) +{ + uint32_t val; + + /* lock PMC_SECURE_SCRATCH22 */ + val = tegra_pmc_read_32(PMC_SECURE_DISABLE2); + val |= PMC_SECURE_DISABLE2_WRITE22_ON; + tegra_pmc_write_32(PMC_SECURE_DISABLE2, val); + + /* lock PMC_SECURE_SCRATCH34/35 */ + val = tegra_pmc_read_32(PMC_SECURE_DISABLE3); + val |= (PMC_SECURE_DISABLE3_WRITE34_ON | + PMC_SECURE_DISABLE3_WRITE35_ON); + tegra_pmc_write_32(PMC_SECURE_DISABLE3, val); +} + +/******************************************************************************* + * Find out if this is the last standing CPU + ******************************************************************************/ +bool tegra_pmc_is_last_on_cpu(void) +{ + int i, cpu = read_mpidr() & MPIDR_CPU_MASK; + uint32_t val = tegra_pmc_read_32(PMC_PWRGATE_STATUS); + bool status = true; + + /* check if this is the last standing CPU */ + for (i = 0; i < PLATFORM_MAX_CPUS_PER_CLUSTER; i++) { + + /* skip the current CPU */ + if (i == cpu) + continue; + + /* are other CPUs already power gated? */ + if ((val & ((uint32_t)1 << pmc_cpu_powergate_id[i])) != 0U) { + status = false; + } + } + + return status; +} + +/******************************************************************************* + * Handler to be called on exiting System suspend. Right now only DPD registers + * are cleared. + ******************************************************************************/ +void tegra_pmc_resume(void) +{ + + /* Clear DPD sample */ + mmio_write_32((TEGRA_PMC_BASE + PMC_IO_DPD_SAMPLE), 0x0); + + /* Clear DPD Enable */ + mmio_write_32((TEGRA_PMC_BASE + PMC_DPD_ENABLE_0), 0x0); +} + +/******************************************************************************* + * Restart the system + ******************************************************************************/ +__dead2 void tegra_pmc_system_reset(void) +{ + uint32_t reg; + + reg = tegra_pmc_read_32(PMC_CONFIG); + reg |= RESET_ENABLE; /* restart */ + tegra_pmc_write_32(PMC_CONFIG, reg); + wfi(); + + ERROR("Tegra System Reset: operation not handled.\n"); + panic(); +} |