Dear all,
I want to read value of the register CCM_CLPCR(Address: 20C_4000h base + 54h offset = 20C_4054h) ,and I my code is following:
void __iomem *mx6_CCM_base = MX6_IO_ADDRESS(CCM_BASE_ADDR); | |
u32 ret32; | |
ret32 = readl(mx6_CCM_base + 0x54); | |
printk(KERN_ERR "---mx6_CCM_base + CLKCTL_CLPCR:%x-----reg--:%x--------\n",mx6_CCM_base + 0x54,ret32); |
So the log is :---mx6_CCM_base + CLKCTL_CLPCR:f40c4054-----reg--:178--------
But I'm so confused that why the addr is 0xf40c4054 not 0x20c4054(this value is on the reference manual).And I also find the following code
/* define virtual address */
#define PERIPBASE_VIRT 0xF0000000
#define MX6_IO_ADDRESS(x) ((x) - PERIPBASE_VIRT)
Maybe I dont know the basic knowedge about these code,could you give me some guideline in details,especially the virtual address?
and before this ,I want to know the value that I read is right?
3Q~
HI tony
you are right: 0xf40c4054 is virtual address, that is 0x20c4054 + PERIPBASE_VIRT,
check attached mx6.h (..linux-3.0.35_4.1.0/arch/arm/plat-mxc/include/mach)
#define PERIPBASE_VIRT | 0xF2000000 |
Best regards
igor
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