[PATCH v3 03/10] arm: arm926ej-s: Add sunxi code

Jesse Taube
2022-01-29T15:23:46Z

Some Allwinner SoCs use ARM926EJ-S core.

Add Allwinner/sunXi specific code to ARM926EJ-S CPU dircetory.

Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Jesse Taube <Mr.Bossman075@gmail.com>
---
V1->V2:
* Fix Copyright notice
* Remove lowlevel_init
* Remove replaced timer.c
* Remove Read CP15 Control Register
* Remove unused start.c
V2->V3:
* Add sdelay to arm926ejs/cpu.c
---
arch/arm/cpu/arm926ejs/Makefile | 1 +
arch/arm/cpu/arm926ejs/cpu.c | 13 ++++++
arch/arm/cpu/arm926ejs/sunxi/Makefile | 5 +++
arch/arm/cpu/arm926ejs/sunxi/config.mk | 6 +++
arch/arm/cpu/arm926ejs/sunxi/fel_utils.S | 33 ++++++++++++++
arch/arm/cpu/arm926ejs/sunxi/u-boot-spl.lds | 48 +++++++++++++++++++++
6 files changed, 106 insertions(+)
create mode 100644 arch/arm/cpu/arm926ejs/sunxi/Makefile
create mode 100644 arch/arm/cpu/arm926ejs/sunxi/config.mk
create mode 100644 arch/arm/cpu/arm926ejs/sunxi/fel_utils.S
create mode 100644 arch/arm/cpu/arm926ejs/sunxi/u-boot-spl.lds

diff --git a/arch/arm/cpu/arm926ejs/Makefile b/arch/arm/cpu/arm926ejs/Makefile
index b901b7c5c9..7f1436d76e 100644
--- a/arch/arm/cpu/arm926ejs/Makefile
+++ b/arch/arm/cpu/arm926ejs/Makefile
@@ -15,6 +15,7 @@ endif
obj-$(CONFIG_MX27) += mx27/
obj-$(if $(filter mxs,$(SOC)),y) += mxs/
obj-$(if $(filter spear,$(SOC)),y) += spear/
+obj-$(CONFIG_ARCH_SUNXI) += sunxi/

# some files can only build in ARM or THUMB2, not THUMB1

diff --git a/arch/arm/cpu/arm926ejs/cpu.c b/arch/arm/cpu/arm926ejs/cpu.c
index 93d7a02ed4..2ce413a7f8 100644
--- a/arch/arm/cpu/arm926ejs/cpu.c
+++ b/arch/arm/cpu/arm926ejs/cpu.c
@@ -21,6 +21,19 @@

static void cache_flush(void);

+/************************************************************
+ * sdelay() - simple spin loop. Will be constant time as
+ * its generally used in bypass conditions only. This
+ * is necessary until timers are accessible.
+ *
+ * not inline to increase chances its in cache when called
+ *************************************************************/
+void sdelay(unsigned long loops)
+{
+ __asm__ volatile ("1:\n" "subs %0, %1, #1\n"
+ "bne 1b":"=r" (loops):"0"(loops));
+}
+
int cleanup_before_linux (void)
{
/*
diff --git a/arch/arm/cpu/arm926ejs/sunxi/Makefile b/arch/arm/cpu/arm926ejs/sunxi/Makefile
new file mode 100644
index 0000000000..7d8b959dcd
--- /dev/null
+++ b/arch/arm/cpu/arm926ejs/sunxi/Makefile
@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0+
+# (C) Copyright 2012 Henrik Nordstrom <henrik@henriknordstrom.net>
+
+obj-y += fel_utils.o
+CFLAGS_fel_utils.o := -marm
diff --git a/arch/arm/cpu/arm926ejs/sunxi/config.mk b/arch/arm/cpu/arm926ejs/sunxi/config.mk
new file mode 100644
index 0000000000..76ffec9df6
--- /dev/null
+++ b/arch/arm/cpu/arm926ejs/sunxi/config.mk
@@ -0,0 +1,6 @@
+# Build a combined spl + u-boot image
+ifdef CONFIG_SPL
+ifndef CONFIG_SPL_BUILD
+ALL-y += u-boot-sunxi-with-spl.bin
+endif
+endif
diff --git a/arch/arm/cpu/arm926ejs/sunxi/fel_utils.S b/arch/arm/cpu/arm926ejs/sunxi/fel_utils.S
new file mode 100644
index 0000000000..08be7ed11a
--- /dev/null
+++ b/arch/arm/cpu/arm926ejs/sunxi/fel_utils.S
@@ -0,0 +1,33 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Utility functions for FEL mode.
+ *
+ * Copyright (c) 2015 Google, Inc
+ */
+
+#include <asm-offsets.h>
+#include <config.h>
+#include <asm/system.h>
+#include <linux/linkage.h>
+
+ENTRY(save_boot_params)
+ ldr r0, =fel_stash
+ str sp, [r0, #0]
+ str lr, [r0, #4]
+ mrs lr, cpsr @ Read CPSR
+ str lr, [r0, #8]
+ mrc p15, 0, lr, c1, c0, 0 @ Read CP15 SCTLR Register
+ str lr, [r0, #12]
+ b save_boot_params_ret
+ENDPROC(save_boot_params)
+
+ENTRY(return_to_fel)
+ mov sp, r0
+ mov lr, r1
+ ldr r0, =fel_stash
+ ldr r1, [r0, #16]
+ mcr p15, 0, r1, c1, c0, 0 @ Write CP15 Control Register
+ ldr r1, [r0, #12]
+ msr cpsr, r1 @ Write CPSR
+ bx lr
+ENDPROC(return_to_fel)
diff --git a/arch/arm/cpu/arm926ejs/sunxi/u-boot-spl.lds b/arch/arm/cpu/arm926ejs/sunxi/u-boot-spl.lds
new file mode 100644
index 0000000000..9a000ac5d3
--- /dev/null
+++ b/arch/arm/cpu/arm926ejs/sunxi/u-boot-spl.lds
@@ -0,0 +1,48 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * (C) Copyright 2018
+ * Icenowy Zheng <icenowy@aosc.io>
+ *
+ * Based on arch/arm/cpu/armv7/sunxi/u-boot-spl.lds:
+ */
+MEMORY { .sram : ORIGIN = CONFIG_SPL_TEXT_BASE,\
+ LENGTH = CONFIG_SPL_MAX_SIZE }
+MEMORY { .sdram : ORIGIN = CONFIG_SPL_BSS_START_ADDR, \
+ LENGTH = CONFIG_SPL_BSS_MAX_SIZE }
+
+OUTPUT_FORMAT("elf32-littlearm", "elf32-littlearm", "elf32-littlearm")
+OUTPUT_ARCH(arm)
+ENTRY(_start)
+SECTIONS
+{
+ .text :
+ {
+ __start = .;
+ *(.vectors)
+ *(.text*)
+ } > .sram
+
+ . = ALIGN(4);
+ .rodata : { *(SORT_BY_ALIGNMENT(.rodata*)) } >.sram
+
+ . = ALIGN(4);
+ .data : { *(SORT_BY_ALIGNMENT(.data*)) } >.sram
+
+ . = ALIGN(4);
+ .u_boot_list : {
+ KEEP(*(SORT(.u_boot_list*)));
+ } > .sram
+
+ . = ALIGN(4);
+ __image_copy_end = .;
+ _end = .;
+
+ .bss :
+ {
+ . = ALIGN(4);
+ __bss_start = .;
+ *(.bss*)
+ . = ALIGN(4);
+ __bss_end = .;
+ } > .sdram
+}
--
2.34.1