Messages in this thread | | | Date | Mon, 20 Oct 2008 07:04:39 -0600 | From | Matthew Wilcox <> | Subject | Re: [PATCH] x86, ioremap: use %pR in printk |
| |
On Mon, Oct 20, 2008 at 01:36:02PM +0200, Ingo Molnar wrote: > One open question would be whether to set the width to 8 on 32-bit > platforms and 16 on 64-bit platforms - right now it's 8 on both. Since > this is specifically a 'physical address' thing it might make sense to > extend that on 64-bit systems. (although it's quite a bit of screen real > estate so i think the current width of 8 should be fine)
Maybe we should let architectures configure it -- after all, they know the real size of a physical address. I'm thinking something like this:
#ifndef PHYS_ADDR_T_SIZE #ifdef CONFIG_64BIT #define PHYS_ADDR_T_SIZE 64 #else #define PHYS_ADDR_T_SIZE 32 #endif #endif
static char *phys_addr_string(char *buf, char *end, phys_addr_t *val, int field_width, int precision, int flags) { /* room for the actual number, the "0x" and the final zero */ char sym[2*sizeof(phys_addr_t) + 3]; char *p = sym, *pend = sym + sizeof(sym); int size = DIV_ROUND_UP(PHYS_ADDR_T_SIZE, 4);
p = number(p, pend, *val, 16, size, -1, SPECIAL | SMALL | ZEROPAD); *p = 0;
return string(buf, end, sym, field_width, precision, flags); }
Architectures can define PHYS_ADDR_T_SIZE to a variable if they want to be able to detect it at boot-time. Or just define it to a number (eg 36 for PAE).
By the way, the patch I'm replying to has a bug; you mis-sized 'sym'. It needs three extra bytes, not two.
-- Matthew Wilcox Intel Open Source Technology Centre "Bill, look, we understand that you're interested in selling us this operating system, but compare it to ours. We can't possibly take such a retrograde step."
| |