Tegra194: drivers: SE and RNG1/PKA1 context save support
This patch adds the driver, to implement the programming sequence to
save/restore hardware context, during System Suspend/Resume.
Change-Id: If851a81cd4e699b58a0055d0be7f145759792ee9
Signed-off-by: Steven Kao <skao@nvidia.com>
Signed-off-by: Jeff Tsai <jefft@nvidia.com>
diff --git a/plat/nvidia/tegra/soc/t194/drivers/se/se.c b/plat/nvidia/tegra/soc/t194/drivers/se/se.c
new file mode 100644
index 0000000..3df670c
--- /dev/null
+++ b/plat/nvidia/tegra/soc/t194/drivers/se/se.c
@@ -0,0 +1,213 @@
+/*
+ * Copyright (c) 2019, NVIDIA CORPORATION. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+#include <errno.h>
+#include <stdbool.h>
+
+#include <arch_helpers.h>
+#include <common/debug.h>
+#include <drivers/delay_timer.h>
+#include <lib/mmio.h>
+#include <lib/psci/psci.h>
+#include <tegra_platform.h>
+
+#include "se_private.h"
+
+/*******************************************************************************
+ * Constants and Macros
+ ******************************************************************************/
+#define ERR_STATUS_SW_CLEAR U(0xFFFFFFFF)
+#define INT_STATUS_SW_CLEAR U(0xFFFFFFFF)
+#define MAX_TIMEOUT_MS U(100) /* Timeout in 100ms */
+#define NUM_SE_REGS_TO_SAVE U(4)
+
+/*******************************************************************************
+ * Data structure and global variables
+ ******************************************************************************/
+static uint32_t se_regs[NUM_SE_REGS_TO_SAVE];
+
+/*
+ * Check that SE operation has completed after kickoff.
+ *
+ * This function is invoked after an SE operation has been started,
+ * and it checks the following conditions:
+ *
+ * 1. SE_STATUS = IDLE
+ * 2. AHB bus data transfer is complete.
+ * 3. SE_ERR_STATUS is clean.
+ */
+static bool tegra_se_is_operation_complete(void)
+{
+ uint32_t val = 0, timeout = 0, sha_status, aes_status;
+ int32_t ret = 0;
+ bool se_is_busy, txn_has_errors, txn_successful;
+
+ /*
+ * Poll the status register to check if the operation
+ * completed.
+ */
+ do {
+ val = tegra_se_read_32(CTX_SAVE_AUTO_STATUS);
+ se_is_busy = !!(val & CTX_SAVE_AUTO_SE_BUSY);
+
+ /* sleep until SE finishes */
+ if (se_is_busy) {
+ mdelay(1);
+ timeout++;
+ }
+
+ } while (se_is_busy && (timeout < MAX_TIMEOUT_MS));
+
+ /* any transaction errors? */
+ txn_has_errors = (tegra_se_read_32(SHA_ERR_STATUS) != 0U) ||
+ (tegra_se_read_32(AES0_ERR_STATUS) != 0U);
+
+ /* transaction successful? */
+ sha_status = tegra_se_read_32(SHA_INT_STATUS) & SHA_SE_OP_DONE;
+ aes_status = tegra_se_read_32(AES0_INT_STATUS) & AES0_SE_OP_DONE;
+ txn_successful = (sha_status == SHA_SE_OP_DONE) &&
+ (aes_status == AES0_SE_OP_DONE);
+
+ if ((timeout == MAX_TIMEOUT_MS) || txn_has_errors || !txn_successful) {
+ ERROR("%s: Atomic context save operation failed!\n",
+ __func__);
+ ret = -ECANCELED;
+ }
+
+ return (ret == 0);
+}
+
+/*
+ * Wait for SE engine to be idle and clear any pending interrupts, before
+ * starting the next SE operation.
+ */
+static bool tegra_se_is_ready(void)
+{
+ int32_t ret = 0;
+ uint32_t val = 0, timeout = 0;
+ bool se_is_ready;
+
+ /* Wait for previous operation to finish */
+ do {
+ val = tegra_se_read_32(CTX_SAVE_AUTO_STATUS);
+ se_is_ready = (val == CTX_SAVE_AUTO_SE_READY);
+
+ /* sleep until SE is ready */
+ if (!se_is_ready) {
+ mdelay(1);
+ timeout++;
+ }
+
+ } while (!se_is_ready && (timeout < MAX_TIMEOUT_MS));
+
+ if (timeout == MAX_TIMEOUT_MS) {
+ ERROR("%s: SE is not ready!\n", __func__);
+ ret = -ETIMEDOUT;
+ }
+
+ /* Clear any pending interrupts from previous operation */
+ tegra_se_write_32(AES0_INT_STATUS, INT_STATUS_SW_CLEAR);
+ tegra_se_write_32(AES1_INT_STATUS, INT_STATUS_SW_CLEAR);
+ tegra_se_write_32(RSA_INT_STATUS, INT_STATUS_SW_CLEAR);
+ tegra_se_write_32(SHA_INT_STATUS, INT_STATUS_SW_CLEAR);
+
+ /* Clear error status for each engine seen from current port */
+ tegra_se_write_32(AES0_ERR_STATUS, ERR_STATUS_SW_CLEAR);
+ tegra_se_write_32(AES1_ERR_STATUS, ERR_STATUS_SW_CLEAR);
+ tegra_se_write_32(RSA_ERR_STATUS, ERR_STATUS_SW_CLEAR);
+ tegra_se_write_32(SHA_ERR_STATUS, ERR_STATUS_SW_CLEAR);
+
+ return (ret == 0);
+}
+
+/*
+ * During System Suspend, this handler triggers the hardware context
+ * save operation.
+ */
+static int32_t tegra_se_save_context(void)
+{
+ int32_t ret = -ECANCELED;
+
+ /*
+ * 1. Ensure all SE Driver including RNG1/PKA1 are shut down.
+ * TSEC/R5s are powergated/idle. All tasks on SE1~SE4, RNG1,
+ * PKA1 are wrapped up. SE0 is ready for use.
+ * 2. Clear interrupt/error in SE0 status register.
+ * 3. Scrub SE0 register to avoid false failure for illegal
+ * configuration. Probably not needed, dependent on HW
+ * implementation.
+ * 4. Check SE is ready for HW CTX_SAVE by polling
+ * SE_CTX_SAVE_AUTO_STATUS.SE_READY.
+ *
+ * Steps 1-4 are executed by tegra_se_is_ready().
+ *
+ * 5. Issue context save command.
+ * 6. Check SE is busy with CTX_SAVE, the command in step5 was not
+ * dropped for ongoing traffic in any of SE port/engine.
+ * 7. Poll SE register or wait for SE APB interrupt for task completion
+ * a. Polling: Read SE_CTX_SAVE_AUTO_STATUS.BUSY till it reports IDLE
+ * b. Interrupt: After receiving interrupt from SE APB, read
+ * SE_CTX_SAVE_AUTO_STATUS.BUSY till it reports IDLE.
+ * 8. Check AES0 and SHA ERR_STATUS to ensure no error case.
+ * 9. Check AES0 and SHA INT_STATUS to ensure operation has successfully
+ * completed.
+ *
+ * Steps 6-9 are executed by tegra_se_is_operation_complete().
+ */
+ if (tegra_se_is_ready()) {
+
+ /* Issue context save command */
+ tegra_se_write_32(AES0_OPERATION, SE_OP_CTX_SAVE);
+
+ /* Wait for operation to finish */
+ if (tegra_se_is_operation_complete()) {
+ ret = 0;
+ }
+ }
+
+ return ret;
+}
+
+/*
+ * Handler to power down the SE hardware blocks - SE, RNG1 and PKA1. This
+ * needs to be called only during System Suspend.
+ */
+int32_t tegra_se_suspend(void)
+{
+ int32_t ret = 0;
+
+ /* save SE registers */
+ se_regs[0] = mmio_read_32(TEGRA_SE0_BASE + SE0_MUTEX_WATCHDOG_NS_LIMIT);
+ se_regs[1] = mmio_read_32(TEGRA_SE0_BASE + SE0_AES0_ENTROPY_SRC_AGE_CTRL);
+ se_regs[2] = mmio_read_32(TEGRA_RNG1_BASE + RNG1_MUTEX_WATCHDOG_NS_LIMIT);
+ se_regs[3] = mmio_read_32(TEGRA_PKA1_BASE + PKA1_MUTEX_WATCHDOG_NS_LIMIT);
+
+ /* Save SE context. The BootROM restores it during System Resume */
+ ret = tegra_se_save_context();
+ if (ret != 0) {
+ ERROR("%s: context save failed (%d)\n", __func__, ret);
+ }
+
+ return ret;
+}
+
+/*
+ * Handler to power up the SE hardware block(s) during System Resume.
+ */
+void tegra_se_resume(void)
+{
+ /*
+ * When TZ takes over after System Resume, TZ should first reconfigure
+ * SE_MUTEX_WATCHDOG_NS_LIMIT, PKA1_MUTEX_WATCHDOG_NS_LIMIT,
+ * RNG1_MUTEX_WATCHDOG_NS_LIMIT and SE_ENTROPY_SRC_AGE_CTRL before
+ * other operations.
+ */
+ mmio_write_32(TEGRA_SE0_BASE + SE0_MUTEX_WATCHDOG_NS_LIMIT, se_regs[0]);
+ mmio_write_32(TEGRA_SE0_BASE + SE0_AES0_ENTROPY_SRC_AGE_CTRL, se_regs[1]);
+ mmio_write_32(TEGRA_RNG1_BASE + RNG1_MUTEX_WATCHDOG_NS_LIMIT, se_regs[2]);
+ mmio_write_32(TEGRA_PKA1_BASE + PKA1_MUTEX_WATCHDOG_NS_LIMIT, se_regs[3]);
+}
diff --git a/plat/nvidia/tegra/soc/t194/drivers/se/se_private.h b/plat/nvidia/tegra/soc/t194/drivers/se/se_private.h
new file mode 100644
index 0000000..7d531bb
--- /dev/null
+++ b/plat/nvidia/tegra/soc/t194/drivers/se/se_private.h
@@ -0,0 +1,84 @@
+/*
+ * Copyright (c) 2019, NVIDIA CORPORATION. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef __SE_PRIVATE_H__
+#define __SE_PRIVATE_H__
+
+#include <lib/utils_def.h>
+
+/* SE0_INT_ENABLE_0 */
+#define SE0_INT_ENABLE U(0x88)
+#define SE0_DISABLE_ALL_INT U(0x0)
+
+/* SE0_INT_STATUS_0 */
+#define SE0_INT_STATUS U(0x8C)
+#define SE0_CLEAR_ALL_INT_STATUS U(0x3F)
+
+/* SE0_SHA_INT_STATUS_0 */
+#define SHA_INT_STATUS U(0x184)
+#define SHA_SE_OP_DONE (U(1) << 4)
+
+/* SE0_SHA_ERR_STATUS_0 */
+#define SHA_ERR_STATUS U(0x18C)
+
+/* SE0_AES0_INT_STATUS_0 */
+#define AES0_INT_STATUS U(0x2F0)
+#define AES0_SE_OP_DONE (U(1) << 4)
+
+/* SE0_AES0_ERR_STATUS_0 */
+#define AES0_ERR_STATUS U(0x2F8)
+
+/* SE0_AES1_INT_STATUS_0 */
+#define AES1_INT_STATUS U(0x4F0)
+
+/* SE0_AES1_ERR_STATUS_0 */
+#define AES1_ERR_STATUS U(0x4F8)
+
+/* SE0_RSA_INT_STATUS_0 */
+#define RSA_INT_STATUS U(0x758)
+
+/* SE0_RSA_ERR_STATUS_0 */
+#define RSA_ERR_STATUS U(0x760)
+
+/* SE0_AES0_OPERATION_0 */
+#define AES0_OPERATION U(0x238)
+#define OP_MASK_BITS U(0x7)
+#define SE_OP_CTX_SAVE U(0x3)
+
+/* SE0_AES0_CTX_SAVE_CONFIG_0 */
+#define CTX_SAVE_CONFIG U(0x2D4)
+
+/* SE0_AES0_CTX_SAVE_AUTO_STATUS_0 */
+#define CTX_SAVE_AUTO_STATUS U(0x300)
+#define CTX_SAVE_AUTO_SE_READY U(0xFF)
+#define CTX_SAVE_AUTO_SE_BUSY (U(0x1) << 31)
+
+/* SE0_AES0_CTX_SAVE_AUTO_CTRL_0 */
+#define CTX_SAVE_AUTO_CTRL U(0x304)
+#define SE_CTX_SAVE_AUTO_EN (U(0x1) << 0)
+#define SE_CTX_SAVE_AUTO_LOCK_EN (U(0x1) << 1)
+
+/* SE0_AES0_CTX_SAVE_AUTO_START_ADDR_0 */
+#define CTX_SAVE_AUTO_START_ADDR U(0x308)
+
+/* SE0_AES0_CTX_SAVE_AUTO_START_ADDR_HI_0 */
+#define CTX_SAVE_AUTO_START_ADDR_HI U(0x30C)
+
+/*******************************************************************************
+ * Inline functions definition
+ ******************************************************************************/
+
+static inline uint32_t tegra_se_read_32(uint32_t offset)
+{
+ return mmio_read_32(TEGRA_SE0_BASE + offset);
+}
+
+static inline void tegra_se_write_32(uint32_t offset, uint32_t val)
+{
+ mmio_write_32(TEGRA_SE0_BASE + offset, val);
+}
+
+#endif /* __SE_PRIVATE_H__ */