chip/mt8192_scp: add memory maps

Adds memory maps for mapping SCP address to AP address and vice versa.

BRANCH=none
BUG=b:146213943
BUG=b:156222459
TEST=make BOARD=asurada_scp

Signed-off-by: Tzung-Bi Shih <tzungbi@chromium.org>
Change-Id: I5e5e34044f54d304bcbe591bf48d6e955d4ed512
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2306900
Reviewed-by: Jett Rink <jettrink@chromium.org>
Reviewed-by: Eric Yilun Lin <yllin@chromium.org>

4 files changed, 145 insertions, 28 deletions

diff --git a/chip/mt8192_scp/build.mk b/chip/mt8192_scp/build.mk
index 86ba6a499c..0925ff2245 100644
--- a/chip/mt8192_scp/build.mk
+++ b/chip/mt8192_scp/build.mk
@@ -12,6 +12,7 @@ CORE:=riscv-rv32i
 chip-y+=clock.o
 chip-y+=gpio.o
 chip-y+=intc.o
+chip-y+=memmap.o
 chip-y+=system.o
 chip-y+=uart.o
 
diff --git a/chip/mt8192_scp/memmap.c b/chip/mt8192_scp/memmap.c
new file mode 100644
index 0000000000..63fa4f8fc5
--- /dev/null
+++ b/chip/mt8192_scp/memmap.c
@@ -0,0 +1,111 @@
+/* Copyright 2020 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "registers.h"
+#include "stdint.h"
+
+/*
+ * Map SCP address (bits 31~28) to AP address
+ *
+ * SCP address	AP address	Note
+ *
+ * 0x0000_0000			SRAM
+ * 0x1000_0000	0x6000_0000	un-cached DRAM
+ * 0x2000_0000	0x7000_0000	un-cached DRAM
+ * 0x3000_0000
+ *
+ * 0x4000_0000
+ * 0x5000_0000	0x0000_0000
+ * 0x6000_0000	0x1000_0000
+ * 0x7000_0000	0xa000_0000
+ *
+ * 0x8000_0000
+ * 0x9000_0000	0x8000_0000
+ * 0xa000_0000	0x9000_0000
+ * 0xb000_0000
+ *
+ * 0xc000_0000	0x8000_0000
+ * 0xd000_0000	0x2000_0000
+ * 0xe000_0000	0x3000_0000
+ * 0xf000_0000	0x5000_0000
+ */
+
+#define REMAP_ADDR_SHIFT		28
+#define REMAP_ADDR_LSB_MASK		(BIT(REMAP_ADDR_SHIFT) - 1)
+#define REMAP_ADDR_MSB_MASK		((~0) << REMAP_ADDR_SHIFT)
+#define MAP_INVALID 0xff
+
+static const uint8_t addr_map[16] = {
+	MAP_INVALID,	/* SRAM */
+	0x6,		/* ext_addr_0x1 */
+	0x7,		/* ext_addr_0x2 */
+	MAP_INVALID,	/* no ext_addr_0x3 */
+
+	MAP_INVALID,	/* no ext_addr_0x4 */
+	0x0,		/* ext_addr_0x5 */
+	0x1,		/* ext_addr_0x6 */
+	0xa,		/* ext_addr_0x7 */
+
+	MAP_INVALID,	/* no ext_addr_0x8 */
+	0x8,		/* ext_addr_0x9 */
+	0x9,		/* ext_addr_0xa */
+	MAP_INVALID,	/* no ext_addr_0xb */
+
+	0x8,		/* ext_addr_0xc */
+	0x2,		/* ext_addr_0xd */
+	0x3,		/* ext_addr_0xe */
+	0x5,		/* ext_addr_0xf */
+};
+
+void memmap_init(void)
+{
+	SCP_R_REMAP_0X0123 =
+		(uint32_t)addr_map[0x1] << 8 |
+		(uint32_t)addr_map[0x2] << 16;
+
+	SCP_R_REMAP_0X4567 =
+		(uint32_t)addr_map[0x5] << 8 |
+		(uint32_t)addr_map[0x6] << 16 |
+		(uint32_t)addr_map[0x7] << 24;
+
+	SCP_R_REMAP_0X89AB =
+		(uint32_t)addr_map[0x9] << 8 |
+		(uint32_t)addr_map[0xa] << 16;
+
+	SCP_R_REMAP_0XCDEF =
+		(uint32_t)addr_map[0xc] |
+		(uint32_t)addr_map[0xd] << 8 |
+		(uint32_t)addr_map[0xe] << 16 |
+		(uint32_t)addr_map[0xf] << 24;
+}
+
+int memmap_ap_to_scp(uintptr_t ap_addr, uintptr_t *scp_addr)
+{
+	int i;
+	uint8_t msb = ap_addr >> REMAP_ADDR_SHIFT;
+
+	for (i = 0; i < ARRAY_SIZE(addr_map); ++i) {
+		if (addr_map[i] != msb)
+			continue;
+
+		*scp_addr = (ap_addr & REMAP_ADDR_LSB_MASK) |
+			(i << REMAP_ADDR_SHIFT);
+		return EC_SUCCESS;
+	}
+
+	return EC_ERROR_INVAL;
+}
+
+int memmap_scp_to_ap(uintptr_t scp_addr, uintptr_t *ap_addr)
+{
+	int i = scp_addr >> REMAP_ADDR_SHIFT;
+
+	if (addr_map[i] == MAP_INVALID)
+		return EC_ERROR_INVAL;
+
+	*ap_addr = (scp_addr & REMAP_ADDR_LSB_MASK) |
+		(addr_map[i] << REMAP_ADDR_SHIFT);
+	return EC_SUCCESS;
+}
diff --git a/chip/mt8192_scp/memmap.h b/chip/mt8192_scp/memmap.h
new file mode 100644
index 0000000000..0857c9a89e
--- /dev/null
+++ b/chip/mt8192_scp/memmap.h
@@ -0,0 +1,31 @@
+/* Copyright 2020 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef __CROS_EC_MEMMAP_H
+#define __CROS_EC_MEMMAP_H
+
+#include "stdint.h"
+
+void memmap_init(void);
+
+/**
+ * Translate AP addr to SCP addr.
+ *
+ * @param ap_addr		AP address to translate
+ * @param scp_addr		Translated AP address
+ * @return			EC_SUCCESS or EC_ERROR_INVAL
+ */
+int memmap_ap_to_scp(uintptr_t ap_addr, uintptr_t *scp_addr);
+
+/**
+ * Translate SCP addr to AP addr.
+ *
+ * @param scp_addr		SCP address to translate
+ * @param ap_addr		Translated SCP address
+ * @return			EC_SUCCESS or EC_ERROR_INVAL
+ */
+int memmap_scp_to_ap(uintptr_t scp_addr, uintptr_t *ap_addr);
+
+#endif /* #ifndef __CROS_EC_MEMMAP_H */
diff --git a/chip/mt8192_scp/system.c b/chip/mt8192_scp/system.c
index 7a68209625..3c5b6c837b 100644
--- a/chip/mt8192_scp/system.c
+++ b/chip/mt8192_scp/system.c
@@ -5,39 +5,13 @@
 
 /* System : hardware specific implementation */
 
+#include "memmap.h"
 #include "registers.h"
 #include "system.h"
 
-static void scp_remap_init(void)
-{
-	/*
-	 *  external address	SCP address
-	 *
-	 *  0x10000000		0x60000000
-	 *  0x20000000		0x70000000
-	 *  0x30000000
-	 *  0x40000000
-	 *  0x50000000
-	 *  0x60000000		0x10000000
-	 *  0x70000000		0xA0000000
-	 *  0x80000000
-	 *  0x90000000		0x80000000
-	 *  0xA0000000		0x90000000
-	 *  0xB0000000
-	 *  0xC0000000		0x80000000
-	 *  0xD0000000		0x20000000
-	 *  0xE0000000		0x30000000
-	 *  0xF0000000		0x50000000
-	 */
-	SCP_R_REMAP_0X0123 = 0x00070600;
-	SCP_R_REMAP_0X4567 = 0x0A010000;
-	SCP_R_REMAP_0X89AB = 0x00090800;
-	SCP_R_REMAP_0XCDEF = 0x05030208;
-}
-
 void system_pre_init(void)
 {
-	scp_remap_init();
+	memmap_init();
 	/* Disable jump (it has only RW) and enable MPU. */
 	/* TODO: implement MPU */
 	system_disable_jump();