Commit 200b7a8d authored by Tony Lindgren's avatar Tony Lindgren Committed by Russell King
Browse files

ARM: 5884/1: arm: Fix DCC console for v7 



Without this patch arch/arm/compressed/head.S defaults to generic
DCC code that does not work for v7.

For more information on the v7 DCC, see Cortex-A8 TRM
"12.11.1 Debug communications channel".

To use it with post 2.6.33-rc1 or later, you need to have:

CONFIG_DEBUG_LL=y
ONFIG_DEBUG_ICEDCC=y
CONFIG_EARLY_PRINTK=y

Earlier kernels need commit 93fd03a8
backported.

Tested on omap3430.

Signed-off-by: default avatarTony Lindgren <tony@atomide.com>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent a7b22962

arch/arm/boot/compressed/head.S

+8 −0
Original line number Diff line number Diff line
@@ -27,6 +27,14 @@ 
		.macro	writeb, ch, rb

		mcr	p14, 0, \ch, c0, c5, 0

		.endm

#elif defined(CONFIG_CPU_V7)

		.macro	loadsp, rb

		.endm

		.macro	writeb, ch, rb

wait:		mrc	p14, 0, pc, c0, c1, 0

		bcs	wait

		mcr	p14, 0, \ch, c0, c5, 0

		.endm

#elif defined(CONFIG_CPU_XSCALE)

		.macro	loadsp, rb

		.endm

arch/arm/boot/compressed/misc.c

+12 −0
Original line number Diff line number Diff line
@@ -53,6 +53,18 @@ static void icedcc_putc(int ch) 


	asm("mcr p14, 0, %0, c0, c5, 0" : : "r" (ch));

}



#elif defined(CONFIG_CPU_V7)



static void icedcc_putc(int ch)

{

	asm(

	"wait:	mrc	p14, 0, pc, c0, c1, 0			\n\

		bcs	wait					\n\

		mcr     p14, 0, %0, c0, c5, 0			"

	: : "r" (ch));

}



#elif defined(CONFIG_CPU_XSCALE)



static void icedcc_putc(int ch)

arch/arm/kernel/debug.S

+20 −0
Original line number Diff line number Diff line
@@ -49,6 +49,26 @@ 
1002:

		.endm



#elif defined(CONFIG_CPU_V7)



		.macro	addruart, rx

		.endm



		.macro	senduart, rd, rx

		mcr	p14, 0, \rd, c0, c5, 0

		.endm



		.macro	busyuart, rd, rx

busy:		mrc	p14, 0, pc, c0, c1, 0

		bcs	busy

		.endm



		.macro	waituart, rd, rx

wait:		mrc	p14, 0, pc, c0, c1, 0

		bcs	wait



		.endm



#elif defined(CONFIG_CPU_XSCALE)



		.macro	addruart, rx

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