refactor(mediatek): smc registration services

To modularize SMC handler, provide macro function in mtk_sip_svc.h.
Drivers register SMC name with value in mtk_sip_def.h, and bind the SMC
handler with the SMC ID by calling DECLARE_SMC_HANDLER macro.

MTK_SIP_SMC_FROM_BL33_TABLE expand the SMC table as switch-case table
statically. DECLARE_SMC_HANDLER wrap SMC handlers with a structure and
put in a section.
During cold boot initialization, in MTK_EARLY_PLAT_INIT level parse the
section to assign each handler with an index. Each SMC request can be
identified with switch-case and take the index to call into
corresponding SMC handler.

Signed-off-by: Leon Chen <leon.chen@mediatek.com>
Change-Id: I03da212c786de0ec0ea646ba906065ecfcd82571

1 files changed, 233 insertions, 0 deletions

diff --git a/plat/mediatek/common/mtk_smc_handlers.c b/plat/mediatek/common/mtk_smc_handlers.c
new file mode 100644
index 000000000..24b978c87
--- /dev/null
+++ b/plat/mediatek/common/mtk_smc_handlers.c
@@ -0,0 +1,233 @@
+/*
+ * Copyright (c) 2022, MediaTek Inc. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+#include <errno.h>
+#include <common/debug.h>
+#include <common/runtime_svc.h>
+#include <cold_boot.h>
+#include <lib/mtk_init/mtk_init.h>
+#include <mtk_sip_svc.h>
+
+#define SMC_HANDLER_DEBUG(...) VERBOSE(__VA_ARGS__)
+#define SMC_HANDLER_DEBUG_NOT_IMP_MSG "%s[0x%x] smc handler not implemented\n"
+#define SMC_HANDLER_DEBUG_START_MSG "%s[0x%x] smc handler start, smc desc. index:%d\n"
+#define SMC_HANDLER_DEBUG_END_MSG "%s[0x%x] smc handler end\n"
+
+/*
+ * These macros below are used to identify SIP calls from Kernel,
+ * Hypervisor, or 2ndBootloader
+ */
+#define SIP_FID_ORI_MASK	(0xc000)
+#define SIP_FID_ORI_SHIFT	(14)
+#define SIP_FID_KERNEL		(0x0)
+#define SIP_FID_KERNEL_VIA_GZ	(0x1)
+#define SIP_FID_GZ		(0x2)
+
+#define GET_SMC_ORI(_fid)	(((_fid) & SIP_FID_ORI_MASK) >> SIP_FID_ORI_SHIFT)
+#define GET_SMC_ORI_NUM(_fid)	((_fid) & ~(SIP_FID_ORI_MASK))
+
+#define is_from_nsel2(_ori)	(_ori == SIP_FID_GZ)
+#define is_from_bl33(_ori) \
+	((_ori != SIP_FID_GZ) && (is_el1_2nd_bootloader() == 1))
+#define is_from_nsel1(_ori) \
+	(((_ori == SIP_FID_KERNEL) || \
+	 (_ori == SIP_FID_KERNEL_VIA_GZ)) && \
+	 (is_el1_2nd_bootloader() == 0))
+
+#define is_smc_forbidden(_ori) (_ori == SIP_FID_KERNEL_VIA_GZ)
+
+#define MASK_32_BIT (0xffffffffU)
+#define SMC_ID_EXPAND_AS_SMC_OPERATION(_smc_id, _smc_num) \
+	case _smc_id##_AARCH32: \
+	{ \
+		x1 = x1 & MASK_32_BIT; \
+		x2 = x2 & MASK_32_BIT; \
+		x3 = x3 & MASK_32_BIT; \
+		x4 = x4 & MASK_32_BIT; \
+	} \
+	case _smc_id##_AARCH64: \
+	{ \
+		if (_smc_id##_descriptor_index < 0) { \
+			SMC_HANDLER_DEBUG(SMC_HANDLER_DEBUG_NOT_IMP_MSG, #_smc_id, smc_id); \
+			break; \
+		} \
+		if (_smc_id##_descriptor_index >= smc_id_descriptor_max) { \
+			SMC_HANDLER_DEBUG("smc descriptor index[%d] exceed max[%d]\n", \
+					  _smc_id##_descriptor_index, smc_id_descriptor_max); \
+			break; \
+		} \
+		SMC_HANDLER_DEBUG(SMC_HANDLER_DEBUG_START_MSG, #_smc_id, smc_id, \
+				  _smc_id##_descriptor_index); \
+		ret  = smc_handler_pool[_smc_id##_descriptor_index].smc_handler(x1,\
+				x2, x3, x4, handle, &smc_ret); \
+		SMC_HANDLER_DEBUG(SMC_HANDLER_DEBUG_END_MSG, #_smc_id, smc_id); \
+		break; \
+	}
+
+#define SMC_ID_EXPAND_AS_DESCRIPTOR_INDEX(_smc_id, _smc_num) \
+	short _smc_id##_descriptor_index __section("mtk_plat_ro") = -1;
+
+MTK_SIP_SMC_FROM_BL33_TABLE(SMC_ID_EXPAND_AS_DESCRIPTOR_INDEX);
+MTK_SIP_SMC_FROM_NS_EL1_TABLE(SMC_ID_EXPAND_AS_DESCRIPTOR_INDEX);
+
+IMPORT_SYM(uintptr_t, __MTK_SMC_POOL_START__, MTK_SMC_POOL_START);
+IMPORT_SYM(uintptr_t, __MTK_SMC_POOL_END_UNALIGNED__, MTK_SMC_POOL_END_UNALIGNED);
+
+static const struct smc_descriptor *smc_handler_pool;
+static short smc_id_descriptor_max;
+
+#if !MTK_SIP_KERNEL_BOOT_ENABLE
+/*
+ * If there is no SMC request needs to be served in 2nd bootloader,
+ * disable the service path inherently.
+ */
+bool is_el1_2nd_bootloader(void)
+{
+	return false;
+}
+#endif
+
+static void print_smc_descriptor(const struct smc_descriptor pool[])
+{
+	const struct smc_descriptor *p_smc_desc;
+
+	INFO("print smc descriptor pool\n");
+	for (p_smc_desc = &pool[0];
+	     (char *)p_smc_desc < (char *)MTK_SMC_POOL_END_UNALIGNED;
+	     p_smc_desc++) {
+		INFO("descriptor name:%s\n", p_smc_desc->smc_name);
+		INFO("descriptor index:%d\n", *p_smc_desc->smc_descriptor_index);
+		INFO("smc id 32:0x%x, smc id 64:0x%x\n",
+		     p_smc_desc->smc_id_aarch32, p_smc_desc->smc_id_aarch64);
+	}
+}
+
+static int mtk_smc_handler_init(void)
+{
+	const struct smc_descriptor *iter;
+	short index_cnt;
+	int ret = 0;
+
+	smc_handler_pool = (const struct smc_descriptor *)MTK_SMC_POOL_START;
+	/* Designate descriptor index point to smc_handler_pool */
+	for (index_cnt = 0, iter = &smc_handler_pool[0];
+	     (char *)iter < (char *)MTK_SMC_POOL_END_UNALIGNED;
+	     iter++, index_cnt++) {
+		if (index_cnt < 0) {
+			SMC_HANDLER_DEBUG("smc handler pool index overflow!\n");
+			ret = -EPERM;
+			assert(0);
+			break;
+		}
+		*(iter->smc_descriptor_index) = index_cnt;
+	}
+	smc_id_descriptor_max = index_cnt;
+	print_smc_descriptor(smc_handler_pool);
+	return ret;
+}
+MTK_EARLY_PLAT_INIT(mtk_smc_handler_init);
+
+/* This function handles Mediatek defined SiP Calls from Bootloader */
+static uintptr_t mtk_smc_handler_bl33(uint32_t smc_id,
+				      u_register_t x1,
+				      u_register_t x2,
+				      u_register_t x3,
+				      u_register_t x4,
+				      void *cookie,
+				      void *handle,
+				      u_register_t flags)
+{
+	uintptr_t ret = MTK_SIP_E_SUCCESS;
+	struct smccc_res smc_ret = {0};
+
+	switch (smc_id) {
+		MTK_SIP_SMC_FROM_BL33_TABLE(SMC_ID_EXPAND_AS_SMC_OPERATION);
+	default:
+		INFO("BL33 SMC ID:0x%x not supported\n", smc_id);
+		ret = SMC_UNK;
+		break;
+	}
+	SMC_RET4(handle, ret, smc_ret.a1, smc_ret.a2, smc_ret.a3);
+}
+
+/* This function handles Mediatek defined SiP Calls from Kernel */
+static uintptr_t mtk_smc_handler_nsel1(uint32_t smc_id,
+				       u_register_t x1,
+				       u_register_t x2,
+				       u_register_t x3,
+				       u_register_t x4,
+				       void *cookie,
+				       void *handle,
+				       u_register_t flags)
+{
+	uintptr_t ret = MTK_SIP_E_SUCCESS;
+	struct smccc_res smc_ret = {0};
+
+	switch (smc_id) {
+		MTK_SIP_SMC_FROM_NS_EL1_TABLE(SMC_ID_EXPAND_AS_SMC_OPERATION);
+	default:
+		INFO("NSEL1 SMC ID:0x%x not supported\n", smc_id);
+		ret = SMC_UNK;
+		break;
+	}
+	SMC_RET4(handle, ret, smc_ret.a1, smc_ret.a2, smc_ret.a3);
+}
+
+static uintptr_t mtk_smc_handler(uint32_t smc_id,
+				 u_register_t x1,
+				 u_register_t x2,
+				 u_register_t x3,
+				 u_register_t x4,
+				 void *cookie,
+				 void *handle,
+				 u_register_t flags)
+{
+	uintptr_t ret = SMC_UNK;
+	uint32_t ns;
+	uint32_t smc_ori;
+	uint32_t smc_num;
+
+	/* Get SMC Originator bit 14.15 */
+	smc_ori = GET_SMC_ORI(smc_id);
+	/* Get SMC Number. Clean bit 14.15 */
+	smc_num = GET_SMC_ORI_NUM(smc_id);
+
+	/* Determine which security state this SMC originated from */
+	ns = is_caller_non_secure(flags);
+
+	if (ns && is_smc_forbidden(smc_ori)) {
+		ERROR("%s: Forbidden SMC call (0x%x)\n", __func__, smc_id);
+		SMC_RET1(handle, ret);
+	}
+
+	if (!ns) {
+		/* SiP SMC service secure world's call */
+		INFO("Secure SMC ID:0x%x not supported\n", smc_id);
+		SMC_RET1(handle, ret);
+	}
+	if (is_from_bl33(smc_ori)) {
+		/* SiP SMC service secure bootloader's call */
+		return mtk_smc_handler_bl33(smc_num, x1, x2, x3, x4,
+					    cookie, handle, flags);
+	} else if (is_from_nsel1(smc_ori)) {
+		/* SiP SMC service kernel's call */
+		return mtk_smc_handler_nsel1(smc_num, x1, x2, x3, x4,
+					     cookie, handle, flags);
+	}
+	INFO("SMC ID:0x%x not supported\n", smc_id);
+	SMC_RET1(handle, ret);
+}
+
+/* Define a runtime service descriptor for fast SMC calls */
+DECLARE_RT_SVC(
+	mtk_smc_handler,
+	OEN_SIP_START,
+	OEN_SIP_END,
+	SMC_TYPE_FAST,
+	NULL,
+	mtk_smc_handler
+);