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[bsp] faster startup for cortex-a 

If the application defines dozens of global variables,
the speed of clearing the bss segment will be slower.

Because icache can be enabled before the mmu enabled.
Therefore, in order to speed up the process of clearing the BSS segment,
enable icache needs to be put ahead.
This commit is contained in:
xiaoguang_ma 2022-11-25 18:04:35 +09:00
parent 82cf0cb1de
commit 16f6157b1e
1 changed files with 7 additions and 4 deletions
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11
libcpu/arm/cortex-a/start_gcc.S
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@ -122,6 +122,13 @@ secondary_loop:
b secondary_loop b secondary_loop
normal_setup: normal_setup:
/* enable I cache + branch prediction */
mrc p15, 0, r0, c1, c0, 0
orr r0, r0, #(1<<12)
orr r0, r0, #(1<<11)
mcr p15, 0, r0, c1, c0, 0
/* setup stack */ /* setup stack */
bl stack_setup bl stack_setup
@ -142,10 +149,6 @@ bss_loop:
mcr p15, 0, r1, c1, c0, 1 //enable smp mcr p15, 0, r1, c1, c0, 1 //enable smp
#endif #endif
/* enable branch prediction */
mrc p15, 0, r0, c1, c0, 0
orr r0, r0, #(1<<11)
mcr p15, 0, r0, c1, c0, 0
/* initialize the mmu table and enable mmu */ /* initialize the mmu table and enable mmu */
ldr r0, =platform_mem_desc ldr r0, =platform_mem_desc