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-rw-r--r--arch/arm/Kconfig2
-rw-r--r--arch/arm/Kconfig.debug64
-rw-r--r--arch/arm/include/asm/macro.h2
-rw-r--r--arch/arm/include/debug/8250.S52
-rw-r--r--arch/arm/lib/Makefile2
-rw-r--r--arch/arm/lib/debug.S136
6 files changed, 257 insertions, 1 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 22eb2d5..79ccc06 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -950,4 +950,6 @@ source "board/woodburn/Kconfig"
source "board/xaeniax/Kconfig"
source "board/zipitz2/Kconfig"
+source "arch/arm/Kconfig.debug"
+
endmenu
diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug
new file mode 100644
index 0000000..624bcf4
--- /dev/null
+++ b/arch/arm/Kconfig.debug
@@ -0,0 +1,64 @@
+menu "ARM debug"
+
+config DEBUG_LL
+ bool "Low-level debugging functions"
+ depends on !ARM64
+ help
+ Say Y here to include definitions of printascii, printch, printhex
+ in U-Boot. This is helpful if you are debugging code that
+ executes before the console is initialized.
+
+choice
+ prompt "Low-level debugging port"
+ depends on DEBUG_LL
+
+ config DEBUG_LL_UART_8250
+ bool "Low-level debugging via 8250 UART"
+ help
+ Say Y here if you wish the debug print routes to direct
+ their output to an 8250 UART. You can use this option
+ to provide the parameters for the 8250 UART rather than
+ selecting one of the platform specific options above if
+ you know the parameters for the port.
+
+ This option is preferred over the platform specific
+ options; the platform specific options are deprecated
+ and will be soon removed.
+
+endchoice
+
+config DEBUG_LL_INCLUDE
+ string
+ depends on DEBUG_LL
+ default "debug/8250.S" if DEBUG_LL_UART_8250 || DEBUG_UART_8250
+ default "mach/debug-macro.S"
+
+# Compatibility options for 8250
+config DEBUG_UART_8250
+ bool
+
+config DEBUG_UART_PHYS
+ hex "Physical base address of debug UART"
+ depends on DEBUG_LL_UART_8250 || DEBUG_UART_8250
+
+# This is not used in U-Boot
+config DEBUG_UART_VIRT
+ hex
+ default DEBUG_UART_PHYS
+ depends on DEBUG_LL_UART_8250 || DEBUG_UART_8250
+
+config DEBUG_UART_8250_SHIFT
+ int "Register offset shift for the 8250 debug UART"
+ depends on DEBUG_LL_UART_8250 || DEBUG_UART_8250
+ default 2
+
+config DEBUG_UART_8250_WORD
+ bool "Use 32-bit accesses for 8250 UART"
+ depends on DEBUG_LL_UART_8250 || DEBUG_UART_8250
+ depends on DEBUG_UART_8250_SHIFT >= 2
+
+config DEBUG_UART_8250_FLOW_CONTROL
+ bool "Enable flow control for 8250 UART"
+ depends on DEBUG_LL_UART_8250 || DEBUG_UART_8250
+
+endmenu
diff --git a/arch/arm/include/asm/macro.h b/arch/arm/include/asm/macro.h
index 541b443..1c8c425 100644
--- a/arch/arm/include/asm/macro.h
+++ b/arch/arm/include/asm/macro.h
@@ -193,7 +193,7 @@ lr .req x30
0 : wfi
ldr \wreg2, [\xreg1, GICC_AIAR]
str \wreg2, [\xreg1, GICC_AEOIR]
- and \wreg2, \wreg2, #3ff
+ and \wreg2, \wreg2, #0x3ff
cbnz \wreg2, 0b
.endm
#endif
diff --git a/arch/arm/include/debug/8250.S b/arch/arm/include/debug/8250.S
new file mode 100644
index 0000000..d47a892
--- /dev/null
+++ b/arch/arm/include/debug/8250.S
@@ -0,0 +1,52 @@
+/*
+ * arch/arm/include/debug/8250.S
+ *
+ * Copyright (C) 1994-2013 Russell King
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+#include <linux/serial_reg.h>
+
+ .macro addruart, rp, rv, tmp
+ ldr \rp, =CONFIG_DEBUG_UART_PHYS
+ ldr \rv, =CONFIG_DEBUG_UART_VIRT
+ .endm
+
+#ifdef CONFIG_DEBUG_UART_8250_WORD
+ .macro store, rd, rx:vararg
+ str \rd, \rx
+ .endm
+
+ .macro load, rd, rx:vararg
+ ldr \rd, \rx
+ .endm
+#else
+ .macro store, rd, rx:vararg
+ strb \rd, \rx
+ .endm
+
+ .macro load, rd, rx:vararg
+ ldrb \rd, \rx
+ .endm
+#endif
+
+#define UART_SHIFT CONFIG_DEBUG_UART_8250_SHIFT
+
+ .macro senduart,rd,rx
+ store \rd, [\rx, #UART_TX << UART_SHIFT]
+ .endm
+
+ .macro busyuart,rd,rx
+1002: load \rd, [\rx, #UART_LSR << UART_SHIFT]
+ and \rd, \rd, #UART_LSR_TEMT | UART_LSR_THRE
+ teq \rd, #UART_LSR_TEMT | UART_LSR_THRE
+ bne 1002b
+ .endm
+
+ .macro waituart,rd,rx
+#ifdef CONFIG_DEBUG_UART_8250_FLOW_CONTROL
+1001: load \rd, [\rx, #UART_MSR << UART_SHIFT]
+ tst \rd, #UART_MSR_CTS
+ beq 1001b
+#endif
+ .endm
diff --git a/arch/arm/lib/Makefile b/arch/arm/lib/Makefile
index 1ef2400..d74e4b8 100644
--- a/arch/arm/lib/Makefile
+++ b/arch/arm/lib/Makefile
@@ -48,6 +48,8 @@ ifndef CONFIG_ARM64
obj-y += cache-cp15.o
endif
+obj-$(CONFIG_DEBUG_LL) += debug.o
+
# For EABI conformant tool chains, provide eabi_compat()
ifneq (,$(findstring -mabi=aapcs-linux,$(PLATFORM_CPPFLAGS)))
extra-y += eabi_compat.o
diff --git a/arch/arm/lib/debug.S b/arch/arm/lib/debug.S
new file mode 100644
index 0000000..760ba74
--- /dev/null
+++ b/arch/arm/lib/debug.S
@@ -0,0 +1,136 @@
+/*
+ * linux/arch/arm/kernel/debug.S
+ *
+ * Copyright (C) 1994-1999 Russell King
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
+ * 32-bit debugging code
+ */
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+ .text
+
+/*
+ * Some debugging routines (useful if you've got MM problems and
+ * printk isn't working). For DEBUGGING ONLY!!! Do not leave
+ * references to these in a production kernel!
+ */
+
+#if !defined(CONFIG_DEBUG_SEMIHOSTING)
+#include CONFIG_DEBUG_LL_INCLUDE
+#endif
+
+#ifdef CONFIG_MMU
+ .macro addruart_current, rx, tmp1, tmp2
+ addruart \tmp1, \tmp2, \rx
+ mrc p15, 0, \rx, c1, c0
+ tst \rx, #1
+ moveq \rx, \tmp1
+ movne \rx, \tmp2
+ .endm
+
+#else /* !CONFIG_MMU */
+ .macro addruart_current, rx, tmp1, tmp2
+ addruart \rx, \tmp1, \tmp2
+ .endm
+
+#endif /* CONFIG_MMU */
+
+/*
+ * Useful debugging routines
+ */
+ENTRY(printhex8)
+ mov r1, #8
+ b printhex
+ENDPROC(printhex8)
+
+ENTRY(printhex4)
+ mov r1, #4
+ b printhex
+ENDPROC(printhex4)
+
+ENTRY(printhex2)
+ mov r1, #2
+printhex: adr r2, hexbuf
+ add r3, r2, r1
+ mov r1, #0
+ strb r1, [r3]
+1: and r1, r0, #15
+ mov r0, r0, lsr #4
+ cmp r1, #10
+ addlt r1, r1, #'0'
+ addge r1, r1, #'a' - 10
+ strb r1, [r3, #-1]!
+ teq r3, r2
+ bne 1b
+ mov r0, r2
+ b printascii
+ENDPROC(printhex2)
+
+hexbuf: .space 16
+
+ .ltorg
+
+#ifndef CONFIG_DEBUG_SEMIHOSTING
+
+ENTRY(printascii)
+ addruart_current r3, r1, r2
+ b 2f
+1: waituart r2, r3
+ senduart r1, r3
+ busyuart r2, r3
+ teq r1, #'\n'
+ moveq r1, #'\r'
+ beq 1b
+2: teq r0, #0
+ ldrneb r1, [r0], #1
+ teqne r1, #0
+ bne 1b
+ mov pc, lr
+ENDPROC(printascii)
+
+ENTRY(printch)
+ addruart_current r3, r1, r2
+ mov r1, r0
+ mov r0, #0
+ b 1b
+ENDPROC(printch)
+
+#ifdef CONFIG_MMU
+ENTRY(debug_ll_addr)
+ addruart r2, r3, ip
+ str r2, [r0]
+ str r3, [r1]
+ mov pc, lr
+ENDPROC(debug_ll_addr)
+#endif
+
+#else
+
+ENTRY(printascii)
+ mov r1, r0
+ mov r0, #0x04 @ SYS_WRITE0
+ ARM( svc #0x123456 )
+ THUMB( svc #0xab )
+ mov pc, lr
+ENDPROC(printascii)
+
+ENTRY(printch)
+ adr r1, hexbuf
+ strb r0, [r1]
+ mov r0, #0x03 @ SYS_WRITEC
+ ARM( svc #0x123456 )
+ THUMB( svc #0xab )
+ mov pc, lr
+ENDPROC(printch)
+
+ENTRY(debug_ll_addr)
+ mov r2, #0
+ str r2, [r0]
+ str r2, [r1]
+ mov pc, lr
+ENDPROC(debug_ll_addr)
+
+#endif