1 /* SPDX-License-Identifier: GPL-2.0+ */
3 * Startup Code for MIPS32 CPU-core
5 * Copyright (c) 2003 Wolfgang Denk <wd@denx.de>
8 #include <asm-offsets.h>
11 #include <asm/regdef.h>
12 #include <asm/mipsregs.h>
14 #ifndef CONFIG_SYS_INIT_SP_ADDR
15 #define CONFIG_SYS_INIT_SP_ADDR (CONFIG_SYS_SDRAM_BASE + \
16 CONFIG_SYS_INIT_SP_OFFSET)
25 # ifdef CONFIG_SYS_LITTLE_ENDIAN
26 # define MIPS64_R_INFO(ssym, r_type3, r_type2, r_type) \
27 (((r_type) << 24) | ((r_type2) << 16) | ((r_type3) << 8) | (ssym))
29 # define MIPS64_R_INFO(ssym, r_type3, r_type2, r_type) \
30 ((r_type) | ((r_type2) << 8) | ((r_type3) << 16) | (ssym) << 24)
32 # define MIPS_RELOC MIPS64_R_INFO(0x00, 0x00, 0x12, 0x03)
33 # define STATUS_SET ST0_KX
39 MTC0 zero, CP0_WATCHLO,\sel
40 mtc0 t1, CP0_WATCHHI,\sel
41 mfc0 t0, CP0_WATCHHI,\sel
46 .macro uhi_mips_exception
47 move k0, t9 # preserve t9 in k0
48 move k1, a0 # preserve a0 in k1
49 li t9, 15 # UHI exception operation
50 li a0, 0 # Use hard register context
51 sdbbp 1 # Invoke UHI operation
56 PTR_LI t1, CONFIG_SYS_INIT_SP_ADDR
57 and sp, t1, t0 # force 16 byte alignment
59 sp, sp, GD_SIZE # reserve space for gd
60 and sp, sp, t0 # force 16 byte alignment
61 move k0, sp # save gd pointer
62 #if CONFIG_VAL(SYS_MALLOC_F_LEN)
63 li t2, CONFIG_VAL(SYS_MALLOC_F_LEN)
65 sp, sp, t2 # reserve space for early malloc
66 and sp, sp, t0 # force 16 byte alignment
77 #if CONFIG_VAL(SYS_MALLOC_F_LEN)
78 PTR_S sp, GD_MALLOC_BASE(k0) # gd->malloc_base offset
83 /* U-Boot entry point */
85 mtc0 zero, CP0_COUNT # clear cp0 count for most accurate boot timing
87 #if defined(CONFIG_SYS_XWAY_EBU_BOOTCFG)
89 * Almost all Lantiq XWAY SoC devices have an external bus unit (EBU) to
90 * access external NOR flashes. If the board boots from NOR flash the
91 * internal BootROM does a blind read at address 0xB0000010 to read the
92 * initial configuration for that EBU in order to access the flash
93 * device with correct parameters. This config option is board-specific.
96 .word CONFIG_SYS_XWAY_EBU_BOOTCFG
99 #if defined(CONFIG_MALTA)
101 * Linux expects the Board ID here.
104 .word 0x00000420 # 0x420 (Malta Board with CoreLV)
108 #if defined(CONFIG_ROM_EXCEPTION_VECTORS)
110 * Exception vector entry points. When running from ROM, an exception
111 * cannot be handled. Halt execution and transfer control to debugger,
112 * if one is attached.
115 /* TLB refill, 32 bit task */
119 /* XTLB refill, 64 bit task */
123 /* Cache error exception */
127 /* General exception */
131 /* Catch interrupt exceptions */
135 /* EJTAG debug exception */
143 #if __mips_isa_rev >= 6
144 mfc0 t0, CP0_CONFIG, 5
145 and t0, t0, MIPS_CONF5_VP
150 mfc0 t0, CP0_GLOBALNUMBER
153 #ifdef CONFIG_ARCH_BMIPS
154 1: mfc0 t0, CP0_DIAGNOSTIC, 3
155 and t0, t0, (1 << 31)
157 1: mfc0 t0, CP0_EBASE
158 and t0, t0, EBASE_CPUNUM
161 /* Hang if this isn't the first CPU in the system */
168 /* Init CP0 Status */
169 4: mfc0 t0, CP0_STATUS
171 or t0, ST0_BEV | ST0_ERL | STATUS_SET
175 * Check whether CP0 Config1 is implemented. If not continue
176 * with legacy Watch register initialization.
183 * Check WR bit in CP0 Config1 to determine if Watch registers
186 mfc0 t0, CP0_CONFIG, 1
191 /* Clear Watch Status bits and disable watch exceptions */
192 li t1, 0x7 # Clear I, R and W conditions
205 MTC0 zero, CP0_WATCHLO
206 mtc0 zero, CP0_WATCHHI
209 /* Clear WP, IV and SW interrupts */
212 /* Clear timer interrupt (CP0_COUNT cleared on branch to 'reset') */
213 mtc0 zero, CP0_COMPARE
215 #ifndef CONFIG_SKIP_LOWLEVEL_INIT
217 and t0, t0, MIPS_CONF_IMPL
218 or t0, t0, CONF_CM_UNCACHED
223 #ifdef CONFIG_MIPS_CM
224 PTR_LA t9, mips_cm_map
229 #ifdef CONFIG_MIPS_INIT_STACK_IN_SRAM
230 /* Set up initial stack and global data */
233 # ifdef CONFIG_DEBUG_UART
234 /* Earliest point to set up debug uart */
235 PTR_LA t9, debug_uart_init
241 #ifndef CONFIG_SKIP_LOWLEVEL_INIT
242 # ifdef CONFIG_SYS_MIPS_CACHE_INIT_RAM_LOAD
243 /* Initialize any external memory */
244 PTR_LA t9, lowlevel_init
249 /* Initialize caches... */
250 PTR_LA t9, mips_cache_reset
254 # ifndef CONFIG_SYS_MIPS_CACHE_INIT_RAM_LOAD
255 /* Initialize any external memory */
256 PTR_LA t9, lowlevel_init
262 #ifndef CONFIG_MIPS_INIT_STACK_IN_SRAM
263 /* Set up initial stack and global data */
266 # ifdef CONFIG_DEBUG_UART
267 /* Earliest point to set up debug uart */
268 PTR_LA t9, debug_uart_init
274 move a0, zero # a0 <-- boot_flags = 0
275 PTR_LA t9, board_init_f