Add SiP service to configure Arm Ethos-N NPU
By default the Arm Ethos-N NPU will boot up in secure mode. In this mode
the non-secure world cannot access the registers needed to use the NPU.
To still allow the non-secure world to use the NPU, a SiP service has
been added that can delegate non-secure access to the registers needed
to use it.
Only the HW_CONFIG for the Arm Juno platform has been updated to include
the device tree for the NPU and the platform currently only loads the
HW_CONFIG in AArch64 builds.
Signed-off-by: Mikael Olsson <mikael.olsson@arm.com>
Change-Id: I65dfd864042ed43faae0a259dcf319cbadb5f3d2
diff --git a/drivers/arm/ethosn/ethosn_smc.c b/drivers/arm/ethosn/ethosn_smc.c
new file mode 100644
index 0000000..299d07c
--- /dev/null
+++ b/drivers/arm/ethosn/ethosn_smc.c
@@ -0,0 +1,164 @@
+/*
+ * Copyright (c) 2021, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <stdint.h>
+#include <stdbool.h>
+
+#include <common/debug.h>
+#include <common/runtime_svc.h>
+#include <drivers/arm/ethosn.h>
+#include <drivers/delay_timer.h>
+#include <lib/mmio.h>
+#include <plat/arm/common/fconf_ethosn_getter.h>
+
+/* Arm Ethos-N NPU (NPU) status */
+#define ETHOSN_STATUS \
+ FCONF_GET_PROPERTY(hw_config, ethosn_config, status)
+
+/* Number of NPU cores available */
+#define ETHOSN_NUM_CORES \
+ FCONF_GET_PROPERTY(hw_config, ethosn_config, num_cores)
+
+/* Address to an NPU core */
+#define ETHOSN_CORE_ADDR(core_idx) \
+ FCONF_GET_PROPERTY(hw_config, ethosn_core_addr, core_idx)
+
+/* NPU core sec registry address */
+#define ETHOSN_CORE_SEC_REG(core_addr, reg_offset) \
+ (core_addr + reg_offset)
+
+/* Reset timeout in us */
+#define ETHOSN_RESET_TIMEOUT_US U(10 * 1000 * 1000)
+#define ETHOSN_RESET_WAIT_US U(1)
+
+#define SEC_DEL_REG U(0x0004)
+#define SEC_DEL_VAL U(0x81C)
+#define SEC_DEL_EXCC_MASK U(0x20)
+
+#define SEC_SECCTLR_REG U(0x0010)
+#define SEC_SECCTLR_VAL U(0x3)
+
+#define SEC_DEL_MMUSID_REG U(0x2008)
+#define SEC_DEL_MMUSID_VAL U(0x3FFFF)
+
+#define SEC_DEL_ADDR_EXT_REG U(0x201C)
+#define SEC_DEL_ADDR_EXT_VAL U(0x15)
+
+#define SEC_SYSCTRL0_REG U(0x0018)
+#define SEC_SYSCTRL0_SOFT_RESET U(3U << 29)
+#define SEC_SYSCTRL0_HARD_RESET U(1U << 31)
+
+static void ethosn_delegate_to_ns(uintptr_t core_addr)
+{
+ mmio_setbits_32(ETHOSN_CORE_SEC_REG(core_addr, SEC_SECCTLR_REG),
+ SEC_SECCTLR_VAL);
+
+ mmio_setbits_32(ETHOSN_CORE_SEC_REG(core_addr, SEC_DEL_REG),
+ SEC_DEL_VAL);
+
+ mmio_setbits_32(ETHOSN_CORE_SEC_REG(core_addr, SEC_DEL_MMUSID_REG),
+ SEC_DEL_MMUSID_VAL);
+
+ mmio_setbits_32(ETHOSN_CORE_SEC_REG(core_addr, SEC_DEL_ADDR_EXT_REG),
+ SEC_DEL_ADDR_EXT_VAL);
+}
+
+static int ethosn_is_sec(void)
+{
+ if ((mmio_read_32(ETHOSN_CORE_SEC_REG(ETHOSN_CORE_ADDR(0), SEC_DEL_REG))
+ & SEC_DEL_EXCC_MASK) != 0U) {
+ return 0;
+ }
+
+ return 1;
+}
+
+static bool ethosn_reset(uintptr_t core_addr, int hard_reset)
+{
+ unsigned int timeout;
+ const uintptr_t sysctrl0_reg =
+ ETHOSN_CORE_SEC_REG(core_addr, SEC_SYSCTRL0_REG);
+ const uint32_t reset_val = (hard_reset != 0) ? SEC_SYSCTRL0_HARD_RESET
+ : SEC_SYSCTRL0_SOFT_RESET;
+
+ mmio_write_32(sysctrl0_reg, reset_val);
+
+ /* Wait for reset to complete */
+ for (timeout = 0U; timeout < ETHOSN_RESET_TIMEOUT_US;
+ timeout += ETHOSN_RESET_WAIT_US) {
+
+ if ((mmio_read_32(sysctrl0_reg) & reset_val) == 0U) {
+ break;
+ }
+
+ udelay(ETHOSN_RESET_WAIT_US);
+ }
+
+ return timeout < ETHOSN_RESET_TIMEOUT_US;
+}
+
+uintptr_t ethosn_smc_handler(uint32_t smc_fid,
+ u_register_t core_idx,
+ u_register_t x2,
+ u_register_t x3,
+ u_register_t x4,
+ void *cookie,
+ void *handle,
+ u_register_t flags)
+{
+ uintptr_t core_addr;
+ int hard_reset = 0;
+
+ /* Only SiP fast calls are expected */
+ if ((GET_SMC_TYPE(smc_fid) != SMC_TYPE_FAST) ||
+ (GET_SMC_OEN(smc_fid) != OEN_SIP_START)) {
+ SMC_RET1(handle, SMC_UNK);
+ }
+
+ /* Truncate parameters to 32-bits for SMC32 */
+ if (GET_SMC_CC(smc_fid) == SMC_32) {
+ core_idx &= 0xFFFFFFFF;
+ x2 &= 0xFFFFFFFF;
+ x3 &= 0xFFFFFFFF;
+ x4 &= 0xFFFFFFFF;
+ }
+
+ if (!is_ethosn_fid(smc_fid)) {
+ SMC_RET1(handle, SMC_UNK);
+ }
+
+ if (ETHOSN_STATUS == ETHOSN_STATUS_DISABLED) {
+ WARN("ETHOSN: Arm Ethos-N NPU not available\n");
+ SMC_RET1(handle, ETHOSN_NOT_SUPPORTED);
+ }
+
+ switch (smc_fid & FUNCID_NUM_MASK) {
+ case ETHOSN_FNUM_VERSION:
+ SMC_RET2(handle, ETHOSN_VERSION_MAJOR, ETHOSN_VERSION_MINOR);
+ case ETHOSN_FNUM_IS_SEC:
+ SMC_RET1(handle, ethosn_is_sec());
+ case ETHOSN_FNUM_HARD_RESET:
+ hard_reset = 1;
+ /* Fallthrough */
+ case ETHOSN_FNUM_SOFT_RESET:
+ if (core_idx >= ETHOSN_NUM_CORES) {
+ WARN("ETHOSN: core index out of range\n");
+ SMC_RET1(handle, ETHOSN_CORE_IDX_OUT_OF_RANGE);
+ }
+
+ core_addr = ETHOSN_CORE_ADDR(core_idx);
+
+ if (!ethosn_reset(core_addr, hard_reset)) {
+ SMC_RET1(handle, ETHOSN_FAILURE);
+ }
+
+ ethosn_delegate_to_ns(core_addr);
+
+ SMC_RET1(handle, ETHOSN_SUCCESS);
+ default:
+ SMC_RET1(handle, SMC_UNK);
+ }
+}