[OpenBIOS] [PATCH v2] ppc: Set up SLBs for ppc64
Alexander Graf
agraf at suse.de
Sun Nov 21 20:14:04 CET 2010
On 21.11.2010, at 19:53, Andreas Färber wrote:
> Set up SLBs with slbmte instead of mtsrin, suggested by Alex.
>
> v2:
> * Don't initialize 64 SLBs, then invalidate them, as in IBM's application note
> for the 970. Use slbia instead, recommended by Alex.
> * Conditionalize when to use SLB or SR.
>
> Cc: Alexander Graf <agraf at suse.de>
> Signed-off-by: Andreas Färber <andreas.faerber at web.de>
> ---
> arch/ppc/qemu/ofmem.c | 25 ++++++++++++++++++++++---
> 1 files changed, 22 insertions(+), 3 deletions(-)
>
> diff --git a/arch/ppc/qemu/ofmem.c b/arch/ppc/qemu/ofmem.c
> index 72694b3..24f3a25 100644
> --- a/arch/ppc/qemu/ofmem.c
> +++ b/arch/ppc/qemu/ofmem.c
> @@ -387,7 +387,7 @@ void
> setup_mmu( unsigned long ramsize )
> {
> ofmem_t *ofmem;
> - unsigned long sdr1, sr_base;
> + unsigned long sdr1;
> unsigned long hash_base;
> unsigned long hash_mask = 0xfff00000; /* alignment for ppc64 */
> int i;
> @@ -399,13 +399,32 @@ setup_mmu( unsigned long ramsize )
> sdr1 = hash_base | ((HASH_SIZE-1) >> 16);
> asm volatile("mtsdr1 %0" :: "r" (sdr1) );
>
> +#if defined(__powerpc64__) || defined(CONFIG_PPC_64BITSUPPORT)
> +#ifdef CONFIG_PPC_64BITSUPPORT
Phew - too much ifdef for my taste. How about the idea I mentioned in the mail before to just make is_ppc64 return always 0 on ppc32 hosts without compat config option? Then you could also protect the slbia and slbmte and whatever ppc64 specific pieces with #ifdefs but not care about the rest :). Would hopefully make this code a lot more readable!
> + if (is_ppc64()) {
> +#endif
> + /* Segment Lookaside Buffer */
> + asm volatile("slbia" ::: "memory");
Inline function please :)
> + for (i = 0; i < 16; i++) {
> + unsigned long rs = ((0x400 + i) << 12) | (0x10 << 7);
> + unsigned long rb = ((unsigned long)i << 28) | (1 << 27) | i;
> + asm volatile("slbmte %0,%1" :: "r" (rs), "r" (rb) : "memory");
Inline function again
> + }
> + asm volatile("isync" ::: "memory");
And this would be awesome to get as inline function too! :)
Alex
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