linux-kernel - [RFC PATCH 07/10] ARM: mps2: add low-level debug support

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1448447621-17900-8-git-send-email-vladimir.murzin@arm.com>
Date:	Wed, 25 Nov 2015 10:33:38 +0000
From:	Vladimir Murzin <vladimir.murzin@....com>
To:	arnd@...db.de, linux@....linux.org.uk, gregkh@...uxfoundation.org,
	daniel.lezcano@...aro.org, tglx@...utronix.de,
	u.kleine-koenig@...gutronix.de, afaerber@...e.de,
	mcoquelin.stm32@...il.com
Cc:	Mark.Rutland@....com, Pawel.Moll@....com,
	ijc+devicetree@...lion.org.uk, galak@...eaurora.org,
	jslaby@...e.cz, robh+dt@...nel.org, devicetree@...r.kernel.org,
	linux-serial@...r.kernel.org, linux-api@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org
Subject: [RFC PATCH 07/10] ARM: mps2: add low-level debug support

Add low-level debug support for MPS2, so that earlyprintk can be enabled
for debugging early boot issues.

Signed-off-by: Vladimir Murzin <vladimir.murzin@....com>
---
 arch/arm/Kconfig.debug        |   12 +++++++++++-
 arch/arm/include/debug/mps2.S |   27 +++++++++++++++++++++++++++
 2 files changed, 38 insertions(+), 1 deletion(-)
 create mode 100644 arch/arm/include/debug/mps2.S

diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug
index 259c0ca..cfbf09a 100644
--- a/arch/arm/Kconfig.debug
+++ b/arch/arm/Kconfig.debug
@@ -479,6 +479,13 @@ choice
 		  Say Y here if you want kernel low-level debugging support
 		  on MMP UART3.
 
+	config DEBUG_MPS2_UART
+		bool "Kernel low-level debugging message via MPS2 UART0"
+		depends on ARCH_MPS2
+		help
+		  Say Y here if you want kernel low-level debugging support
+		  on MPS2 based platforms.
+
 	config DEBUG_QCOM_UARTDM
 		bool "Kernel low-level debugging messages via QCOM UARTDM"
 		depends on ARCH_QCOM
@@ -1350,6 +1357,7 @@ config DEBUG_LL_INCLUDE
 	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
+	default "debug/mps2.S" if DEBUG_MPS2_UART
 	default "mach/debug-macro.S"
 
 # Compatibility options for PL01x
@@ -1403,6 +1411,7 @@ config DEBUG_UART_PHYS
 	default 0x20068000 if DEBUG_RK29_UART2 || DEBUG_RK3X_UART3
 	default 0x20201000 if DEBUG_BCM2835
 	default 0x3e000000 if DEBUG_BCM_KONA_UART
+	default 0x40004000 if DEBUG_MPS2_UART
 	default 0x4000e400 if DEBUG_LL_UART_EFM32
 	default 0x40081000 if DEBUG_LPC18XX_UART0
 	default 0x40090000 if ARCH_LPC32XX
@@ -1476,7 +1485,8 @@ config DEBUG_UART_PHYS
 		DEBUG_RMOBILE_SCIFA4 || DEBUG_S3C24XX_UART || \
 		DEBUG_UART_BCM63XX || DEBUG_ASM9260_UART || \
 		DEBUG_SIRFSOC_UART || DEBUG_DIGICOLOR_UA0 || \
-		DEBUG_AT91_UART
+		DEBUG_AT91_UART || \
+		DEBUG_MPS2_UART
 
 config DEBUG_UART_VIRT
 	hex "Virtual base address of debug UART"
diff --git a/arch/arm/include/debug/mps2.S b/arch/arm/include/debug/mps2.S
new file mode 100644
index 0000000..0ced0ce
--- /dev/null
+++ b/arch/arm/include/debug/mps2.S
@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2015 ARM Limited
+ *
+ * Author: Vladimir Murzin <vladimir.murzin@....com>
+ *
+ * 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.
+ *
+ */
+
+	.macro	addruart, rp, tmp1, tmp2
+	ldr	\rp, =CONFIG_DEBUG_UART_PHYS
+	.endm
+
+	.macro	senduart, rd, rx
+	strb	\rd, [\rx]		@ Data Register
+	.endm
+
+	.macro	busyuart, rd, rx
+1001:	ldrb	\rd, [\rx, #0x4]	@ State Register
+	tst	\rd, #1			@ busy
+	bne	1001b			@ wait until transmit done
+	.endm
+
+	.macro	waituart,rd,rx
+	.endm
-- 
1.7.9.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/