/* * Copyright (C) 2010,2011 Google, Inc. * Copyright (C) 2011-2012 NVIDIA CORPORATION. All Rights Reserved. * * Author: *	Colin Cross <ccross@google.com> *	Erik Gilling <konkers@google.com> *	Doug Anderson <dianders@chromium.org> *	Stephen Warren <swarren@nvidia.com> * * Portions based on mach-omap2's debug-macro.S * Copyright (C) 1994-1999 Russell King * * This software is licensed under the terms of the GNU General Public * License version 2, as published by the Free Software Foundation, and * may be copied, distributed, and modified under those terms. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the * GNU General Public License for more details. * */ #include <linux/serial_reg.h> #define UART_SHIFT 2 /* Physical addresses */#define TEGRA_CLK_RESET_BASE		0x60006000#define TEGRA_APB_MISC_BASE		0x70000000#define TEGRA_UARTA_BASE		0x70006000#define TEGRA_UARTB_BASE		0x70006040#define TEGRA_UARTC_BASE		0x70006200#define TEGRA_UARTD_BASE		0x70006300#define TEGRA_UARTE_BASE		0x70006400#define TEGRA_PMC_BASE			0x7000e400 #define TEGRA_CLK_RST_DEVICES_L		(TEGRA_CLK_RESET_BASE + 0x04)#define TEGRA_CLK_RST_DEVICES_H		(TEGRA_CLK_RESET_BASE + 0x08)#define TEGRA_CLK_RST_DEVICES_U		(TEGRA_CLK_RESET_BASE + 0x0c)#define TEGRA_CLK_OUT_ENB_L		(TEGRA_CLK_RESET_BASE + 0x10)#define TEGRA_CLK_OUT_ENB_H		(TEGRA_CLK_RESET_BASE + 0x14)#define TEGRA_CLK_OUT_ENB_U		(TEGRA_CLK_RESET_BASE + 0x18)#define TEGRA_PMC_SCRATCH20		(TEGRA_PMC_BASE + 0xa0)#define TEGRA_APB_MISC_GP_HIDREV	(TEGRA_APB_MISC_BASE + 0x804) /* * Must be section-aligned since a section mapping is used early on. * Must not overlap with regions in mach-tegra/io.c:tegra_io_desc[]. */#define UART_VIRTUAL_BASE		0xfe800000 #define checkuart(rp, rv, lhu, bit, uart) \		/* Load address of CLK_RST register */ \		ldr	rp, =TEGRA_CLK_RST_DEVICES_##lhu ; \		/* Load value from CLK_RST register */ \		ldr	rp, [rp, #0] ; \		/* Test UART's reset bit */ \		tst	rp, #(1 << bit) ; \		/* If set, can't use UART; jump to save no UART */ \		bne	90f ; \		/* Load address of CLK_OUT_ENB register */ \		ldr	rp, =TEGRA_CLK_OUT_ENB_##lhu ; \		/* Load value from CLK_OUT_ENB register */ \		ldr	rp, [rp, #0] ; \		/* Test UART's clock enable bit */ \		tst	rp, #(1 << bit) ; \		/* If clear, can't use UART; jump to save no UART */ \		beq	90f ; \		/* Passed all tests, load address of UART registers */ \		ldr	rp, =TEGRA_UART##uart##_BASE ; \		/* Jump to save UART address */ \		b 91f 		.macro  addruart, rp, rv, tmp		adr	\rp, 99f		@ actual addr of 99f		ldr	\rv, [\rp]		@ linked addr is stored there		sub	\rv, \rv, \rp		@ offset between the two		ldr	\rp, [\rp, #4]		@ linked tegra_uart_config		sub	\tmp, \rp, \rv		@ actual tegra_uart_config		ldr	\rp, [\tmp]		@ Load tegra_uart_config		cmp	\rp, #1			@ needs initialization?		bne	100f			@ no; go load the addresses		mov	\rv, #0			@ yes; record init is done		str	\rv, [\tmp] #ifdef CONFIG_TEGRA_DEBUG_UART_AUTO_ODMDATA		/* Check ODMDATA */10:		ldr	\rp, =TEGRA_PMC_SCRATCH20		ldr	\rp, [\rp, #0]		@ Load PMC_SCRATCH20		lsr	\rv, \rp, #18		@ 19:18 are console type		and	\rv, \rv, #3		cmp	\rv, #2			@ 2 and 3 mean DCC, UART		beq	11f			@ some boards swap the meaning		cmp	\rv, #3			@ so accept either		bne	90f11:		lsr	\rv, \rp, #15		@ 17:15 are UART ID		and	\rv, #7			cmp	\rv, #0			@ UART 0?		beq	20f		cmp	\rv, #1			@ UART 1?		beq	21f		cmp	\rv, #2			@ UART 2?		beq	22f		cmp	\rv, #3			@ UART 3?		beq	23f		cmp	\rv, #4			@ UART 4?		beq	24f		b	90f			@ invalid#endif #if defined(CONFIG_TEGRA_DEBUG_UARTA) || \    defined(CONFIG_TEGRA_DEBUG_UART_AUTO_ODMDATA)		/* Check UART A validity */20:		checkuart(\rp, \rv, L, 6, A)#endif #if defined(CONFIG_TEGRA_DEBUG_UARTB) || \    defined(CONFIG_TEGRA_DEBUG_UART_AUTO_ODMDATA)		/* Check UART B validity */21:		checkuart(\rp, \rv, L, 7, B)#endif #if defined(CONFIG_TEGRA_DEBUG_UARTC) || \    defined(CONFIG_TEGRA_DEBUG_UART_AUTO_ODMDATA)		/* Check UART C validity */22:		checkuart(\rp, \rv, H, 23, C)#endif #if defined(CONFIG_TEGRA_DEBUG_UARTD) || \    defined(CONFIG_TEGRA_DEBUG_UART_AUTO_ODMDATA)		/* Check UART D validity */23:		checkuart(\rp, \rv, U, 1, D)#endif #if defined(CONFIG_TEGRA_DEBUG_UARTE) || \    defined(CONFIG_TEGRA_DEBUG_UART_AUTO_ODMDATA)		/* Check UART E validity */24:		checkuart(\rp, \rv, U, 2, E)#endif 		/* No valid UART found */90:		mov	\rp, #0		/* fall through */ 		/* Record whichever UART we chose */91:		str	\rp, [\tmp, #4]		@ Store in tegra_uart_phys		cmp	\rp, #0			@ Valid UART address?		bne	92f			@ Yes, go process it		str	\rp, [\tmp, #8]		@ Store 0 in tegra_uart_virt		b	100f			@ Done92:		and	\rv, \rp, #0xffffff	@ offset within 1MB section		add	\rv, \rv, #UART_VIRTUAL_BASE		str	\rv, [\tmp, #8]		@ Store in tegra_uart_virt		b	100f 		.align99:		.word	.		.word	tegra_uart_config		.ltorg 		/* Load previously selected UART address */100:		ldr	\rp, [\tmp, #4]		@ Load tegra_uart_phys		ldr	\rv, [\tmp, #8]		@ Load tegra_uart_virt		.endm /* * Code below is swiped from <asm/hardware/debug-8250.S>, but add an extra * check to make sure that the UART address is actually valid. */ 		.macro	senduart, rd, rx		cmp	\rx, #0		strneb	\rd, [\rx, #UART_TX << UART_SHIFT]1001:		.endm 		.macro	busyuart, rd, rx		cmp	\rx, #0		beq	1002f1001:		ldrb	\rd, [\rx, #UART_LSR << UART_SHIFT]		and	\rd, \rd, #UART_LSR_THRE		teq	\rd, #UART_LSR_THRE		bne	1001b1002:		.endm 		.macro	waituart, rd, rx#ifdef FLOW_CONTROL		cmp	\rx, #0		beq	1002f1001:		ldrb	\rd, [\rx, #UART_MSR << UART_SHIFT]		tst	\rd, #UART_MSR_CTS		beq	1001b1002:#endif		.endm /* * Storage for the state maintained by the macros above. * * In the kernel proper, this data is located in arch/arm/mach-tegra/tegra.c. * That's because this header is included from multiple files, and we only * want a single copy of the data. In particular, the UART probing code above * assumes it's running using physical addresses. This is true when this file * is included from head.o, but not when included from debug.o. So we need * to share the probe results between the two copies, rather than having * to re-run the probing again later. * * In the decompressor, we put the symbol/storage right here, since common.c * isn't included in the decompressor build. This symbol gets put in .text * even though it's really data, since .data is discarded from the * decompressor. Luckily, .text is writeable in the decompressor, unless * CONFIG_ZBOOT_ROM. That dependency is handled in arch/arm/Kconfig.debug. */#if defined(ZIMAGE)tegra_uart_config:	/* Debug UART initialization required */	.word 1	/* Debug UART physical address */	.word 0	/* Debug UART virtual address */	.word 0#endif