[U-Boot] arm writel in v2010.03-rc1 generate wrong code
zzs213
zzs213 at 126.com
Tue Feb 22 09:06:52 CET 2011
My board is very similar to at91rm9200ek. I have a function to init nor flash bus, like this :
void gfd3000cdb_nor_hw_init(void)
{
at91_mc_t *mc = (at91_mc_t *)AT91_MC_BASE;
writel(CONFIG_SYS_EBI_CFGR_VAL, &(mc->ebi.cfgr));
writel(CONFIG_SYS_SMC_CSR0_VAL, &mc->smc.csr[0]);
}
Which render to the fllowing asm code :
20120f0c <gfd3000cdb_nor_hw_init>:
20120f0c: e3a01000 mov r1, #0 ; 0x0
20120f10: e3e0309b mvn r3, #155 ; 0x9b
20120f14: e5831000 str r1, [r3]
20120f18: e283309b add r3, r3, #155 ; 0x9b
20120f1c: e553208f ldrb r2, [r3, #-143]
20120f20: e3e0207b mvn r2, #123 ; 0x7b
20120f24: e543208f strb r2, [r3, #-143]
20120f28: e553208e ldrb r2, [r3, #-142]
20120f2c: e3a02032 mov r2, #50 ; 0x32
20120f30: e543208e strb r2, [r3, #-142]
20120f34: e553208d ldrb r2, [r3, #-141]
20120f38: e543108d strb r1, [r3, #-141]
20120f3c: e553208c ldrb r2, [r3, #-140]
20120f40: e543108c strb r1, [r3, #-140]
20120f44: e1a0f00e mov pc, lr
It can't work very obviously because it use the target address as four byte address, but my idea is write a 4bytes word
to the target address.
And the cpu dead when I download this code to the board.
Then I change the function to the flowwing form:
void gfd3000cdb_nor_hw_init(void)
{
at91_mc_t *mc = (at91_mc_t *)AT91_MC_BASE;
writel(CONFIG_SYS_EBI_CFGR_VAL, &(mc->ebi.cfgr));
writel(CONFIG_SYS_SMC_CSR0_VAL, (unsigned int)(&mc->smc.csr[0]));
}
It's asm code is :
20120f0c <gfd3000cdb_nor_hw_init>:
20120f0c: e3a02000 mov r2, #0 ; 0x0
20120f10: e3e0309b mvn r3, #155 ; 0x9b
20120f14: e5832000 str r2, [r3]
20120f18: e59f2008 ldr r2, [pc, #8] ; 20120f28 <gfd3000cdb_nor_hw_init+0x1c>
20120f1c: e283300c add r3, r3, #12 ; 0xc
20120f20: e5832000 str r2, [r3]
20120f24: e1a0f00e mov pc, lr
20120f28: 00003284 .word 0x00003284
It's ok. And the board say OK too.
My toolchain is eldk4.2
anybody help me!!
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