From mboxrd@z Thu Jan 1 00:00:00 1970 From: jun.nie@linaro.org (Jun Nie) Date: Sat, 14 Mar 2015 19:49:37 +0800 Subject: [PATCH 02/10] ARM: zx: add low level debug support In-Reply-To: <1426333785-3952-1-git-send-email-jun.nie@linaro.org> References: <1426333785-3952-1-git-send-email-jun.nie@linaro.org> Message-ID: <1426333785-3952-3-git-send-email-jun.nie@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Use the UART0 peripheral for low level debug. Only the UART port 0 is currently supported. Signed-off-by: Jun Nie --- 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