[PATCH 3/5] sunxi: move early "SRAM setup" into separate file

Andre Przywara andre.przywara at arm.com
Tue Jan 25 02:15:15 CET 2022


Currently we do some magic "SRAM setup" MMIO writes in s_init(), copied
from the original BSP U-Boot. The comment speaks of this being required
before DRAM access gets enabled, but there is no indication that this
would actually be required that early.

Move this out of s_init(), into board_init_f(). Since this actually only
affects a very few older SoCs, the actual code goes into the cpu/armv7
directory, to move it out of the way for all other SoCs.

This also uses the opportunity to convert some #ifdefs over to the fancy
IS_ENABLED() macros used in actual C code.

We keep the s_init() stub around for now, since armv8's lowlevel_init
still relies on it.

Signed-off-by: Andre Przywara <andre.przywara at arm.com>
---
 arch/arm/cpu/armv7/sunxi/Makefile |  3 +++
 arch/arm/cpu/armv7/sunxi/sram.c   | 45 +++++++++++++++++++++++++++++++
 arch/arm/mach-sunxi/board.c       | 38 +++++---------------------
 3 files changed, 54 insertions(+), 32 deletions(-)
 create mode 100644 arch/arm/cpu/armv7/sunxi/sram.c

diff --git a/arch/arm/cpu/armv7/sunxi/Makefile b/arch/arm/cpu/armv7/sunxi/Makefile
index 1d40d6a18dc..ad11be78632 100644
--- a/arch/arm/cpu/armv7/sunxi/Makefile
+++ b/arch/arm/cpu/armv7/sunxi/Makefile
@@ -10,6 +10,9 @@ obj-y	+= timer.o
 obj-$(CONFIG_MACH_SUN6I)	+= tzpc.o
 obj-$(CONFIG_MACH_SUN8I_H3)	+= tzpc.o
 
+obj-$(CONFIG_MACH_SUN6I)	+= sram.o
+obj-$(CONFIG_MACH_SUN8I)	+= sram.o
+
 ifndef CONFIG_SPL_BUILD
 obj-$(CONFIG_ARMV7_PSCI)	+= psci.o
 endif
diff --git a/arch/arm/cpu/armv7/sunxi/sram.c b/arch/arm/cpu/armv7/sunxi/sram.c
new file mode 100644
index 00000000000..19395cce17c
--- /dev/null
+++ b/arch/arm/cpu/armv7/sunxi/sram.c
@@ -0,0 +1,45 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * (C) Copyright 2012 Henrik Nordstrom <henrik at henriknordstrom.net>
+ *
+ * (C) Copyright 2007-2011
+ * Allwinner Technology Co., Ltd. <www.allwinnertech.com>
+ * Tom Cubie <tangliang at allwinnertech.com>
+ *
+ * SRAM init for older sunxi SoCs.
+ */
+
+#include <common.h>
+#include <init.h>
+#include <asm/io.h>
+
+void sunxi_sram_init(void)
+{
+	/*
+	 * Undocumented magic taken from boot0, without this DRAM
+	 * access gets messed up (seems cache related).
+	 * The boot0 sources describe this as: "config ema for cache sram"
+	 * Newer SoCs (A83T, H3 and anything beyond) don't need this anymore.
+	 */
+	if (IS_ENABLED(CONFIG_MACH_SUN6I))
+		setbits_le32(SUNXI_SRAMC_BASE + 0x44, 0x1800);
+
+	if (IS_ENABLED(CONFIG_MACH_SUN8I)) {
+		uint version;
+
+		/* Unlock sram version info reg, read it, relock */
+		setbits_le32(SUNXI_SRAMC_BASE + 0x24, (1 << 15));
+		version = readl(SUNXI_SRAMC_BASE + 0x24) >> 16;
+		clrbits_le32(SUNXI_SRAMC_BASE + 0x24, (1 << 15));
+
+		if (IS_ENABLED(CONFIG_MACH_SUN8I_A23)) {
+			if (version == 0x1650)
+				setbits_le32(SUNXI_SRAMC_BASE + 0x44, 0x1800);
+			else /* 0x1661 ? */
+				setbits_le32(SUNXI_SRAMC_BASE + 0x44, 0xc0);
+		} else if (IS_ENABLED(CONFIG_MACH_SUN8I_A33)) {
+			if (version != 0x1667)
+				setbits_le32(SUNXI_SRAMC_BASE + 0x44, 0xc0);
+		}
+	}
+}
diff --git a/arch/arm/mach-sunxi/board.c b/arch/arm/mach-sunxi/board.c
index 8667ddf58e3..42ec02d96e3 100644
--- a/arch/arm/mach-sunxi/board.c
+++ b/arch/arm/mach-sunxi/board.c
@@ -186,38 +186,6 @@ SPL_LOAD_IMAGE_METHOD("FEL", 0, BOOT_DEVICE_BOARD, spl_board_load_image);
 
 void s_init(void)
 {
-	/*
-	 * Undocumented magic taken from boot0, without this DRAM
-	 * access gets messed up (seems cache related).
-	 * The boot0 sources describe this as: "config ema for cache sram"
-	 */
-#if defined CONFIG_MACH_SUN6I
-	setbits_le32(SUNXI_SRAMC_BASE + 0x44, 0x1800);
-#elif defined CONFIG_MACH_SUN8I
-	__maybe_unused uint version;
-
-	/* Unlock sram version info reg, read it, relock */
-	setbits_le32(SUNXI_SRAMC_BASE + 0x24, (1 << 15));
-	version = readl(SUNXI_SRAMC_BASE + 0x24) >> 16;
-	clrbits_le32(SUNXI_SRAMC_BASE + 0x24, (1 << 15));
-
-	/*
-	 * Ideally this would be a switch case, but we do not know exactly
-	 * which versions there are and which version needs which settings,
-	 * so reproduce the per SoC code from the BSP.
-	 */
-#if defined CONFIG_MACH_SUN8I_A23
-	if (version == 0x1650)
-		setbits_le32(SUNXI_SRAMC_BASE + 0x44, 0x1800);
-	else /* 0x1661 ? */
-		setbits_le32(SUNXI_SRAMC_BASE + 0x44, 0xc0);
-#elif defined CONFIG_MACH_SUN8I_A33
-	if (version != 0x1667)
-		setbits_le32(SUNXI_SRAMC_BASE + 0x44, 0xc0);
-#endif
-	/* A83T BSP never modifies SUNXI_SRAMC_BASE + 0x44 */
-	/* No H3 BSP, boot0 seems to not modify SUNXI_SRAMC_BASE + 0x44 */
-#endif
 }
 
 #define SUNXI_INVALID_BOOT_SOURCE	-1
@@ -312,8 +280,14 @@ u32 spl_boot_device(void)
 	return sunxi_get_boot_device();
 }
 
+__weak void sunxi_sram_init(void)
+{
+}
+
 void board_init_f(ulong dummy)
 {
+	sunxi_sram_init();
+
 #if defined CONFIG_MACH_SUN6I || defined CONFIG_MACH_SUN8I_H3
 	/* Enable non-secure access to some peripherals */
 	tzpc_init();
-- 
2.17.6



More information about the U-Boot mailing list