ARM: arch-meson: build memory banks using reported memory from registers

As discussed at [1], the Amlogic Meson GX SoCs can embed a BL31 firmware
and a secondary BL32 firmware.
Since mid-2017, the reserved memory address of the BL31 firmware was moved
and grown for security reasons.

But mainline U-Boot and Linux has the old address and size fixed.

These SoCs have a register interface to get the two firmware reserved
memory start and sizes.

This patch adds a dynamic reservation of the memory zones in the device tree bootmem
reserved memory zone used by the kernel in early boot.
To be complete, the memory zones are also added to the EFI reserved zones.

Depends on patchset "Add support for Amlogic GXL Based SBCs" at [2].

[1] http://lists.infradead.org/pipermail/linux-amlogic/2017-October/004860.html
[2] http://lists.infradead.org/pipermail/linux-amlogic/2017-November/005410.html

Changes since v1:
- switched the #if to if(IS_ENABLED()) to compile all code paths
- renamed function to meson_board_add_reserved_memory()
- added a mem.h header with comment
- updated all boards ft_board_setup()

Changes since RFC v2:
- reduced preprocessor load
- kept Odroid-C2 static memory mapping as exception

Changes since RFC v1:
- switch to fdt rsv mem table and efi reserve memory
- replaced in_le32 by readl()

Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
[trini: Fix warning on khadas-vim over missing <asm/arch/mem.h>
Signed-off-by: Tom Rini <trini@konsulko.com>

12 files changed, 136 insertions, 9 deletions

diff --git a/arch/arm/include/asm/arch-meson/gxbb.h b/arch/arm/include/asm/arch-meson/gxbb.h
index 95a6fe6998..ef63dea449 100644
--- a/arch/arm/include/asm/arch-meson/gxbb.h
+++ b/arch/arm/include/asm/arch-meson/gxbb.h
@@ -7,10 +7,27 @@
 #ifndef __GXBB_H__
 #define __GXBB_H__
 
+#define GXBB_FIRMWARE_MEM_SIZE	0x1000000
+
+#define GXBB_AOBUS_BASE		0xc8100000
 #define GXBB_PERIPHS_BASE	0xc8834400
 #define GXBB_HIU_BASE		0xc883c000
 #define GXBB_ETH_BASE		0xc9410000
 
+/* Always-On Peripherals registers */
+#define GXBB_AO_ADDR(off)	(GXBB_AOBUS_BASE + ((off) << 2))
+
+#define GXBB_AO_SEC_GP_CFG0	GXBB_AO_ADDR(0x90)
+#define GXBB_AO_SEC_GP_CFG3	GXBB_AO_ADDR(0x93)
+#define GXBB_AO_SEC_GP_CFG4	GXBB_AO_ADDR(0x94)
+#define GXBB_AO_SEC_GP_CFG5	GXBB_AO_ADDR(0x95)
+
+#define GXBB_AO_MEM_SIZE_MASK	0xFFFF0000
+#define GXBB_AO_MEM_SIZE_SHIFT	16
+#define GXBB_AO_BL31_RSVMEM_SIZE_MASK	0xFFFF0000
+#define GXBB_AO_BL31_RSVMEM_SIZE_SHIFT	16
+#define GXBB_AO_BL32_RSVMEM_SIZE_MASK	0xFFFF
+
 /* Peripherals registers */
 #define GXBB_PERIPHS_ADDR(off)	(GXBB_PERIPHS_BASE + ((off) << 2))
 
diff --git a/arch/arm/include/asm/arch-meson/mem.h b/arch/arm/include/asm/arch-meson/mem.h
new file mode 100644
index 0000000000..86a8417034
--- /dev/null
+++ b/arch/arm/include/asm/arch-meson/mem.h
@@ -0,0 +1,16 @@
+/*
+ * Copyright (C) 2016 BayLibre, SAS
+ * Author: Neil Armstrong <narmstrong@baylibre.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef __MESON_MEM_H__
+#define __MESON_MEM_H__
+
+/* Configure the reserved memory zones exported by the secure registers
+ * into EFI and DTB reserved memory entries.
+ */
+void meson_gx_init_reserved_memory(void *fdt);
+
+#endif /* __MESON_MEM_H__ */
diff --git a/arch/arm/mach-meson/board.c b/arch/arm/mach-meson/board.c
index e89c6aace9..908a0cae56 100644
--- a/arch/arm/mach-meson/board.c
+++ b/arch/arm/mach-meson/board.c
@@ -11,6 +11,9 @@
 #include <asm/arch/sm.h>
 #include <asm/armv8/mmu.h>
 #include <asm/unaligned.h>
+#include <linux/sizes.h>
+#include <efi_loader.h>
+#include <asm/io.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -34,15 +37,70 @@ int dram_init(void)
 	return 0;
 }
 
-int dram_init_banksize(void)
+phys_size_t get_effective_memsize(void)
 {
-	/* Reserve first 16 MiB of RAM for firmware */
-	gd->bd->bi_dram[0].start = 0x1000000;
-	gd->bd->bi_dram[0].size  = 0xf000000;
-	/* Reserve 2 MiB for ARM Trusted Firmware (BL31) */
-	gd->bd->bi_dram[1].start = 0x10000000;
-	gd->bd->bi_dram[1].size  = gd->ram_size - 0x10200000;
-	return 0;
+	/* Size is reported in MiB, convert it in bytes */
+	return ((readl(GXBB_AO_SEC_GP_CFG0) & GXBB_AO_MEM_SIZE_MASK)
+			>> GXBB_AO_MEM_SIZE_SHIFT) * SZ_1M;
+}
+
+static void meson_board_add_reserved_memory(void *fdt, u64 start, u64 size)
+{
+	int ret;
+
+	ret = fdt_add_mem_rsv(fdt, start, size);
+	if (ret)
+		printf("Could not reserve zone @ 0x%llx\n", start);
+
+	if (IS_ENABLED(CONFIG_EFI_LOADER)) {
+		efi_add_memory_map(start,
+				   ALIGN(size, EFI_PAGE_SIZE) >> EFI_PAGE_SHIFT,
+				   EFI_RESERVED_MEMORY_TYPE, false);
+	}
+}
+
+void meson_gx_init_reserved_memory(void *fdt)
+{
+	u64 bl31_size, bl31_start;
+	u64 bl32_size, bl32_start;
+	u32 reg;
+
+	/*
+	 * Get ARM Trusted Firmware reserved memory zones in :
+	 * - AO_SEC_GP_CFG3: bl32 & bl31 size in KiB, can be 0
+	 * - AO_SEC_GP_CFG5: bl31 physical start address, can be NULL
+	 * - AO_SEC_GP_CFG4: bl32 physical start address, can be NULL
+	 */
+
+	reg = readl(GXBB_AO_SEC_GP_CFG3);
+
+	bl31_size = ((reg & GXBB_AO_BL31_RSVMEM_SIZE_MASK)
+			>> GXBB_AO_BL31_RSVMEM_SIZE_SHIFT) * SZ_1K;
+	bl32_size = (reg & GXBB_AO_BL32_RSVMEM_SIZE_MASK) * SZ_1K;
+
+	bl31_start = readl(GXBB_AO_SEC_GP_CFG5);
+	bl32_start = readl(GXBB_AO_SEC_GP_CFG4);
+
+	/*
+	 * Early Meson GXBB Firmware revisions did not provide the reserved
+	 * memory zones in the registers, keep fixed memory zone handling.
+	 */
+	if (IS_ENABLED(CONFIG_MESON_GXBB) &&
+	    !reg && !bl31_start && !bl32_start) {
+		bl31_start = 0x10000000;
+		bl31_size = 0x200000;
+	}
+
+	/* Add first 16MiB reserved zone */
+	meson_board_add_reserved_memory(fdt, 0, GXBB_FIRMWARE_MEM_SIZE);
+
+	/* Add BL31 reserved zone */
+	if (bl31_start && bl31_size)
+		meson_board_add_reserved_memory(fdt, bl31_start, bl31_size);
+
+	/* Add BL32 reserved zone */
+	if (bl32_start && bl32_size)
+		meson_board_add_reserved_memory(fdt, bl32_start, bl32_size);
 }
 
 void reset_cpu(ulong addr)
diff --git a/board/amlogic/khadas-vim/khadas-vim.c b/board/amlogic/khadas-vim/khadas-vim.c
index db9c292458..5e198569db 100644
--- a/board/amlogic/khadas-vim/khadas-vim.c
+++ b/board/amlogic/khadas-vim/khadas-vim.c
@@ -9,6 +9,7 @@
 #include <dm.h>
 #include <asm/io.h>
 #include <asm/arch/gxbb.h>
+#include <asm/arch/mem.h>
 #include <asm/arch/sm.h>
 #include <asm/arch/eth.h>
 
@@ -47,3 +48,10 @@ int misc_init_r(void)
 
 	return 0;
 }
+
+int ft_board_setup(void *blob, bd_t *bd)
+{
+	meson_gx_init_reserved_memory(blob);
+
+	return 0;
+}
diff --git a/board/amlogic/libretech-cc/libretech-cc.c b/board/amlogic/libretech-cc/libretech-cc.c
index 26c0e78a46..6be6e2ae93 100644
--- a/board/amlogic/libretech-cc/libretech-cc.c
+++ b/board/amlogic/libretech-cc/libretech-cc.c
@@ -11,6 +11,7 @@
 #include <asm/arch/gxbb.h>
 #include <asm/arch/sm.h>
 #include <asm/arch/eth.h>
+#include <asm/arch/mem.h>
 
 #define EFUSE_SN_OFFSET		20
 #define EFUSE_SN_SIZE		16
@@ -51,3 +52,10 @@ int misc_init_r(void)
 
 	return 0;
 }
+
+int ft_board_setup(void *blob, bd_t *bd)
+{
+	meson_gx_init_reserved_memory(blob);
+
+	return 0;
+}
diff --git a/board/amlogic/odroid-c2/odroid-c2.c b/board/amlogic/odroid-c2/odroid-c2.c
index d68d0f1344..0cb571432f 100644
--- a/board/amlogic/odroid-c2/odroid-c2.c
+++ b/board/amlogic/odroid-c2/odroid-c2.c
@@ -10,6 +10,7 @@
 #include <asm/arch/gxbb.h>
 #include <asm/arch/sm.h>
 #include <asm/arch/eth.h>
+#include <asm/arch/mem.h>
 
 #define EFUSE_SN_OFFSET		20
 #define EFUSE_SN_SIZE		16
@@ -54,3 +55,10 @@ int misc_init_r(void)
 
 	return 0;
 }
+
+int ft_board_setup(void *blob, bd_t *bd)
+{
+	meson_gx_init_reserved_memory(blob);
+
+	return 0;
+}
diff --git a/board/amlogic/p212/p212.c b/board/amlogic/p212/p212.c
index 2b6d88ab1b..5fde53438e 100644
--- a/board/amlogic/p212/p212.c
+++ b/board/amlogic/p212/p212.c
@@ -11,6 +11,7 @@
 #include <asm/arch/gxbb.h>
 #include <asm/arch/sm.h>
 #include <asm/arch/eth.h>
+#include <asm/arch/mem.h>
 
 #define EFUSE_SN_OFFSET		20
 #define EFUSE_SN_SIZE		16
@@ -46,3 +47,10 @@ int misc_init_r(void)
 
 	return 0;
 }
+
+int ft_board_setup(void *blob, bd_t *bd)
+{
+	meson_gx_init_reserved_memory(blob);
+
+	return 0;
+}
diff --git a/configs/khadas-vim_defconfig b/configs/khadas-vim_defconfig
index dcccc6915a..f2a30a83e9 100644
--- a/configs/khadas-vim_defconfig
+++ b/configs/khadas-vim_defconfig
@@ -17,6 +17,7 @@ CONFIG_CMD_MMC=y
 CONFIG_CMD_GPIO=y
 # CONFIG_CMD_SETEXPR is not set
 CONFIG_OF_CONTROL=y
+CONFIG_OF_BOARD_SETUP=y
 CONFIG_DM_GPIO=y
 CONFIG_DM_MMC=y
 CONFIG_MMC_MESON_GX=y
diff --git a/configs/libretech-cc_defconfig b/configs/libretech-cc_defconfig
index a63e940761..6583c43c85 100644
--- a/configs/libretech-cc_defconfig
+++ b/configs/libretech-cc_defconfig
@@ -17,6 +17,7 @@ CONFIG_CMD_MMC=y
 CONFIG_CMD_GPIO=y
 # CONFIG_CMD_SETEXPR is not set
 CONFIG_OF_CONTROL=y
+CONFIG_OF_BOARD_SETUP=y
 CONFIG_DM_GPIO=y
 CONFIG_DM_MMC=y
 CONFIG_MMC_MESON_GX=y
diff --git a/configs/odroid-c2_defconfig b/configs/odroid-c2_defconfig
index 1afd2fc111..18d2b6825d 100644
--- a/configs/odroid-c2_defconfig
+++ b/configs/odroid-c2_defconfig
@@ -16,6 +16,7 @@ CONFIG_CMD_I2C=y
 CONFIG_CMD_MMC=y
 # CONFIG_CMD_SETEXPR is not set
 CONFIG_OF_CONTROL=y
+CONFIG_OF_BOARD_SETUP=y
 CONFIG_NET_RANDOM_ETHADDR=y
 CONFIG_DM_GPIO=y
 CONFIG_DM_I2C=y
diff --git a/configs/p212_defconfig b/configs/p212_defconfig
index d4b534954e..b6e788b098 100644
--- a/configs/p212_defconfig
+++ b/configs/p212_defconfig
@@ -17,6 +17,7 @@ CONFIG_CMD_MMC=y
 CONFIG_CMD_GPIO=y
 # CONFIG_CMD_SETEXPR is not set
 CONFIG_OF_CONTROL=y
+CONFIG_OF_BOARD_SETUP=y
 CONFIG_DM_GPIO=y
 CONFIG_DM_MMC=y
 CONFIG_MMC_MESON_GX=y
diff --git a/include/configs/meson-gxbb-common.h b/include/configs/meson-gxbb-common.h
index d88d42de9a..c2b306ad2e 100644
--- a/include/configs/meson-gxbb-common.h
+++ b/include/configs/meson-gxbb-common.h
@@ -10,7 +10,7 @@
 
 #define CONFIG_CPU_ARMV8
 #define CONFIG_REMAKE_ELF
-#define CONFIG_NR_DRAM_BANKS		2
+#define CONFIG_NR_DRAM_BANKS		1
 #define CONFIG_ENV_SIZE			0x2000
 #define CONFIG_SYS_MAXARGS		32
 #define CONFIG_SYS_MALLOC_LEN		(32 << 20)