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Diffstat (limited to 'plat/nvidia/tegra/drivers/pmc/pmc.c')
-rw-r--r--plat/nvidia/tegra/drivers/pmc/pmc.c153
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();
+}