[OpenBIOS] [PATCH] ppc64: Don't set Kp bit on SLB

[Alexander Graf]

On 21.05.2011, at 14:57, Andreas Färber wrote:

> Since QEMU 81762d6dd0d430d87024f2c83e9c4dcc4329fb7d (Clean up
> PowerPC SLB handling code) we never got to the ppc64 OpenBIOS banner.
> 
> According to Alex' debugging this is due to the Kp bit being set.
> 
> The code was supposed to be a 1:1 translation of the old mtsrin
> code, which did not set Kp bit. So don't set Kp bit with slbmte.
> 
> Cc: Alexander Graf <agraf at suse.de>
> Cc: David Gibson <david at gibson.dropbear.id.au>
> Signed-off-by: Andreas Färber <andreas.faerber at web.de>
> ---
> arch/ppc/qemu/ofmem.c |    2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/arch/ppc/qemu/ofmem.c b/arch/ppc/qemu/ofmem.c
> index 297e685..514d129 100644
> --- a/arch/ppc/qemu/ofmem.c
> +++ b/arch/ppc/qemu/ofmem.c
> @@ -497,7 +497,7 @@ setup_mmu(unsigned long ramsize)
> 
>     slbia(); /* Invalidate all SLBs except SLB 0 */
>     for (i = 0; i < 16; i++) {
> -        unsigned long rs = ((0x400 + i) << 12) | (0x10 << 7);
> +        unsigned long rs = ((0x400 + i) << 12) | (0x0 << 7);

I find the y << 7 thing pretty unreadable anyways, so why not just drop it? If you feel like it, just define a few constants that allow you to set Kp and Ks:

agraf at lychee:/home/agraf/release/qemu> grep -n SLB_VSID target-ppc/cpu.h
391:#define SLB_VSID_SHIFT          12
392:#define SLB_VSID_SHIFT_1T       24
393:#define SLB_VSID_SSIZE_SHIFT    62
394:#define SLB_VSID_B              0xc000000000000000ULL
395:#define SLB_VSID_B_256M         0x0000000000000000ULL
396:#define SLB_VSID_B_1T           0x4000000000000000ULL
397:#define SLB_VSID_VSID           0x3FFFFFFFFFFFF000ULL
398:#define SLB_VSID_PTEM           (SLB_VSID_B | SLB_VSID_VSID)
399:#define SLB_VSID_KS             0x0000000000000800ULL
400:#define SLB_VSID_KP             0x0000000000000400ULL
401:#define SLB_VSID_N              0x0000000000000200ULL /* no-execute */
402:#define SLB_VSID_L              0x0000000000000100ULL
403:#define SLB_VSID_C              0x0000000000000080ULL /* class */
404:#define SLB_VSID_LP             0x0000000000000030ULL
405:#define SLB_VSID_ATTR           0x0000000000000FFFULL

Just copy those, replace the << 12 by << SLB_VSID_SHIFT, and then this code will be a lot more readable :)


Alex