alistair23-linux/arch/arm/include/debug/brcmstb.S
Doug Berger 56e4446df9 ARM: brcmstb: Add support for the V7 memory map
The 7278 device is the first device that includes support for the V7
memory map developed for use in 64-bit architecture brcmstb devices.
This map relocates the register physical offset from 0xF0000000 to
0x0000000008000000.

Since the ARM PERIPHBASE value is also relocated in the V7 memory map
we can use its value to determine whether this device uses the new
V7 memory map and therefore where to look for the SUN_TOP_CTRL
register used to identify the chip family.

Signed-off-by: Doug Berger <opendmb@gmail.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
2018-05-09 12:14:42 -07:00

170 lines
5.4 KiB
ArmAsm

/*
* Copyright (C) 2016 Broadcom
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation version 2.
*
* This program is distributed "as is" WITHOUT ANY WARRANTY of any
* kind, whether express or implied; 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>
#include <asm/cputype.h>
/* Physical register offset and virtual register offset */
#define REG_PHYS_BASE 0xf0000000
#define REG_PHYS_BASE_V7 0x08000000
#define REG_VIRT_BASE 0xfc000000
#define REG_PHYS_ADDR(x) ((x) + REG_PHYS_BASE)
#define REG_PHYS_ADDR_V7(x) ((x) + REG_PHYS_BASE_V7)
/* Product id can be read from here */
#define SUN_TOP_CTRL_BASE REG_PHYS_ADDR(0x404000)
#define SUN_TOP_CTRL_BASE_V7 REG_PHYS_ADDR_V7(0x404000)
#define UARTA_3390 REG_PHYS_ADDR(0x40a900)
#define UARTA_7250 REG_PHYS_ADDR(0x40b400)
#define UARTA_7260 REG_PHYS_ADDR(0x40c000)
#define UARTA_7268 UARTA_7260
#define UARTA_7271 UARTA_7268
#define UARTA_7278 REG_PHYS_ADDR_V7(0x40c000)
#define UARTA_7364 REG_PHYS_ADDR(0x40b000)
#define UARTA_7366 UARTA_7364
#define UARTA_74371 REG_PHYS_ADDR(0x406b00)
#define UARTA_7439 REG_PHYS_ADDR(0x40a900)
#define UARTA_7445 REG_PHYS_ADDR(0x40ab00)
#define UART_SHIFT 2
#define checkuart(rp, rv, family_id, family) \
/* Load family id */ \
ldr rp, =family_id ; \
/* Compare SUN_TOP_CTRL value against it */ \
cmp rp, rv ; \
/* Passed test, load address */ \
ldreq rp, =UARTA_##family ; \
/* Jump to save UART address */ \
beq 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 brcmstb_uart_config
sub \tmp, \rp, \rv @ actual brcmstb_uart_config
ldr \rp, [\tmp] @ Load brcmstb_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]
/* Check for V7 memory map if B53 */
mrc p15, 0, \rv, c0, c0, 0 @ get Main ID register
ldr \rp, =ARM_CPU_PART_MASK
and \rv, \rv, \rp
ldr \rp, =ARM_CPU_PART_BRAHMA_B53 @ check for B53 CPU
cmp \rv, \rp
bne 10f
/* if PERIPHBASE doesn't overlap REG_PHYS_BASE use V7 map */
mrc p15, 1, \rv, c15, c3, 0 @ get PERIPHBASE from CBAR
ands \rv, \rv, #REG_PHYS_BASE
ldreq \rp, =SUN_TOP_CTRL_BASE_V7
/* Check SUN_TOP_CTRL base */
10: ldrne \rp, =SUN_TOP_CTRL_BASE @ load SUN_TOP_CTRL PA
ldr \rv, [\rp, #0] @ get register contents
ARM_BE8( rev \rv, \rv )
and \rv, \rv, #0xffffff00 @ strip revision bits [7:0]
/* Chip specific detection starts here */
20: checkuart(\rp, \rv, 0x33900000, 3390)
21: checkuart(\rp, \rv, 0x72500000, 7250)
22: checkuart(\rp, \rv, 0x72600000, 7260)
23: checkuart(\rp, \rv, 0x72680000, 7268)
24: checkuart(\rp, \rv, 0x72710000, 7271)
25: checkuart(\rp, \rv, 0x73640000, 7364)
26: checkuart(\rp, \rv, 0x73660000, 7366)
27: checkuart(\rp, \rv, 0x07437100, 74371)
28: checkuart(\rp, \rv, 0x74390000, 7439)
29: checkuart(\rp, \rv, 0x74450000, 7445)
30: checkuart(\rp, \rv, 0x72780000, 7278)
/* No valid UART found */
90: mov \rp, #0
/* fall through */
/* Record whichever UART we chose */
91: str \rp, [\tmp, #4] @ Store in brcmstb_uart_phys
cmp \rp, #0 @ Valid UART address?
bne 92f @ Yes, go process it
str \rp, [\tmp, #8] @ Store 0 in brcmstb_uart_virt
b 100f @ Done
92: and \rv, \rp, #0xffffff @ offset within 16MB section
add \rv, \rv, #REG_VIRT_BASE
str \rv, [\tmp, #8] @ Store in brcmstb_uart_virt
b 100f
.align
99: .word .
.word brcmstb_uart_config
.ltorg
/* Load previously selected UART address */
100: ldr \rp, [\tmp, #4] @ Load brcmstb_uart_phys
ldr \rv, [\tmp, #8] @ Load brcmstb_uart_virt
.endm
.macro store, rd, rx:vararg
ARM_BE8( rev \rd, \rd )
str \rd, \rx
.endm
.macro load, rd, rx:vararg
ldr \rd, \rx
ARM_BE8( rev \rd, \rd )
.endm
.macro senduart,rd,rx
store \rd, [\rx, #UART_TX << UART_SHIFT]
.endm
.macro busyuart,rd,rx
1002: load \rd, [\rx, #UART_LSR << UART_SHIFT]
and \rd, \rd, #UART_LSR_TEMT | UART_LSR_THRE
teq \rd, #UART_LSR_TEMT | UART_LSR_THRE
bne 1002b
.endm
.macro waituart,rd,rx
.endm
/*
* Storage for the state maintained by the macros above.
*
* In the kernel proper, this data is located in arch/arm/mach-bcm/brcmstb.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)
brcmstb_uart_config:
/* Debug UART initialization required */
.word 1
/* Debug UART physical address */
.word 0
/* Debug UART virtual address */
.word 0
#endif