[PATCH 02/10] ARM: zx: add low level debug support

Jun Nie
2015-03-14T11:49:37Z

Use the UART0 peripheral for low level debug. Only the UART port 0 is
currently supported.

Signed-off-by: Jun Nie <jun.nie@linaro.org>
---
arch/arm/Kconfig.debug | 12 ++++++++++++
arch/arm/include/debug/zx.S | 35 +++++++++++++++++++++++++++++++++++
2 files changed, 47 insertions(+)
create mode 100644 arch/arm/include/debug/zx.S

diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug
index 970de75..b2a0e9a 100644
--- a/arch/arm/Kconfig.debug
+++ b/arch/arm/Kconfig.debug
@@ -1169,6 +1169,17 @@ choice
For more details about semihosting, please see
chapter 8 of DUI0203I_rvct_developer_guide.pdf from ARM Ltd.

+ config DEBUG_ZTE_ZX
+ bool "Use ZTE ZX UART"
+ depends on ARCH_ZX
+ help
+ Say Y here if you are enabling ZTE ZX296702 SOC and need
+ debug uart support.
+
+ This option is preferred over the platform specific
+ options; the platform specific options are deprecated
+ and will be soon removed.
+
config DEBUG_LL_UART_8250
bool "Kernel low-level debugging via 8250 UART"
help
@@ -1315,6 +1326,7 @@ config DEBUG_LL_INCLUDE
default "debug/vexpress.S" if DEBUG_VEXPRESS_UART0_DETECT
default "debug/vf.S" if DEBUG_VF_UART
default "debug/vt8500.S" if DEBUG_VT8500_UART0
+ default "debug/zx.S" if DEBUG_ZTE_ZX
default "debug/zynq.S" if DEBUG_ZYNQ_UART0 || DEBUG_ZYNQ_UART1
default "debug/bcm63xx.S" if DEBUG_UART_BCM63XX
default "debug/digicolor.S" if DEBUG_DIGICOLOR_UA0
diff --git a/arch/arm/include/debug/zx.S b/arch/arm/include/debug/zx.S
new file mode 100644
index 0000000..aa745ac
--- /dev/null
+++ b/arch/arm/include/debug/zx.S
@@ -0,0 +1,35 @@
+/*
+ * Debugging macro include header
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#define UART01x_DR 0x04 /* Data read or write */
+#define UART01x_FR 0x14 /* Flag register (Read only) */
+
+#define UART01x_FR_TXFF 0x020
+
+
+#define UART0_PADDR 0x09405000
+#define UART0_VADDR 0xfc705000
+
+ .macro addruart, rp, rv, tmp
+ ldr \rp, =UART0_PADDR @ physical
+ ldr \rv, =UART0_VADDR @ virtual
+ .endm
+
+ .macro senduart,rd,rx
+ strb \rd, [\rx, #UART01x_DR]
+ .endm
+
+ .macro waituart,rd,rx
+ .endm
+
+ .macro busyuart,rd,rx
+1001: ldr \rd, [\rx, #UART01x_FR]
+ tst \rd, #UART01x_FR_TXFF
+ bne 1001b
+ .endm
--
1.9.1