[U-Boot] arm writel in v2010.03-rc1 generate wrong code

[Jens Scharsig]

Am 2011-02-22 09:06, schrieb zzs213:
> 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!!

I think you need this patch

http://lists.denx.de/pipermail/u-boot/2010-December/084133.html

regards

Jens Scharsig