On Mon, Oct 04, 2010 at 01:19:07AM +0200, Peter Stuge wrote:
Stefan Reinauer wrote:
+config CPU_ADDR_BITS_MASK
Such stuff belongs into an include file, not into Kconfig.
Good point! I agree completely if it works in practise.
Are you guys suggesting something like this?
Index: src/include/cpu/cpu.h
--- src/include/cpu/cpu.h (Revision 5909) +++ src/include/cpu/cpu.h (Arbeitskopie) @@ -27,4 +27,21 @@ /** end of compile time generated pci driver array */ extern struct cpu_driver ecpu_drivers[];
+/*
- Map the number of address space bits supported by the CPU to the
- mask field value as it needs to be written into the upper 32 bits
- of the various MTRRphysMask_MSR MSRs.
- */
+#if defined(CONFIG_CPU_ADDR_BITS) && (CONFIG_CPU_ADDR_BITS == 32) +#define CONFIG_CPU_ADDR_BITS_MASK 0x00000000 +#elif defined(CONFIG_CPU_ADDR_BITS) && (CONFIG_CPU_ADDR_BITS == 36) +#define CONFIG_CPU_ADDR_BITS_MASK 0x0000000f +#elif defined(CONFIG_CPU_ADDR_BITS) && (CONFIG_CPU_ADDR_BITS == 40) +#define CONFIG_CPU_ADDR_BITS_MASK 0x000000ff +#elif defined(CONFIG_CPU_ADDR_BITS) && (CONFIG_CPU_ADDR_BITS == 48) +#define CONFIG_CPU_ADDR_BITS_MASK 0x0000ffff +#else +#error No CPU_ADDR_BITS value was selected or an unknown value was selected +#endif
#endif /* CPU_CPU_H */
I have no idea what others were envisioning, but I would think something like this would work for me.
In a processor-specific file: #define CPU_ADDR_BITS 40
In cpu.h: #define CPU_ADDR_BITS_MASK (0xffff >> (48 - CPU_ADDR_BITS))
or for the future: #define CPU_ADDR_BITS_MASK (0xffffff >> (56 - CPU_ADDR_BITS))
Thanks, Myles