Daniel Laird wrote:
> Update Patch
>
> Fix known bug with MIPS core when using TLB on NXP/Philips PNX8550
>
> Signed-off-by: Daniel Laird <daniel.j.laird@xxxxxxx>
> ---
> tlb-r4k.c | 4 +++
> tlbex.c | 71
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 75 insertions(+)
> ---
> Index: linux-2.6.22.1/arch/mips/mm/tlbex.c
> ===================================================================
> --- linux-2.6.22.1/arch/mips/mm/tlbex.c (revision 8)
> +++ linux-2.6.22.1/arch/mips/mm/tlbex.c (working copy)
> @@ -435,6 +435,9 @@
> label_nopage_tlbm,
> label_smp_pgtable_change,
> label_r3000_write_probe_fail,
> +#ifdef CONFIG_PNX8550
> + label_pnx8550_bac_reset
> +#endif
Please don't use #ifdef where it isn't needed ...
[snip]
> +static void __init build_pnx8550_bug_fix( u32 **p, struct label **l,
> struct reloc **r)
> +{
> +#define MFC0(_reg, _cp, _sel) \
> + ((cop0_op) << OP_SH \
> + | (mfc_op) << RS_SH \
> + | (_reg) << RT_SH \
> + | (_cp) << RD_SH \
> + | (_sel))
> +
> +#define MTC0(_reg, _cp, _sel) \
> + ((cop0_op) << OP_SH \
> + | (mtc_op) << RS_SH \
> + | (_reg) << RT_SH \
> + | (_cp) << RD_SH \
> + | (_sel))
... don't reinvent the wheel ...
[snip]
> @@ -1261,8 +1328,12 @@
> build_get_ptep(&p, K0, K1);
> build_update_entries(&p, K0, K1);
> +#ifndef CONFIG_PNX8550
> build_tlb_write_entry(&p, &l, &r, tlb_random);
> l_leave(&l, p);
> +#else
> + build_pnx8550_bug_fix(&p, &l, &r);
> +#endif
... and make that a runtime check.
> i_eret(&p); /* return from trap */
> #ifdef CONFIG_64BIT
> Index: linux-2.6.22.1/arch/mips/mm/tlb-r4k.c
> ===================================================================
> --- linux-2.6.22.1/arch/mips/mm/tlb-r4k.c (revision 8)
> +++ linux-2.6.22.1/arch/mips/mm/tlb-r4k.c (working copy)
> @@ -456,7 +456,11 @@
> */
> probe_tlb(config);
> write_c0_pagemask(PM_DEFAULT_MASK);
> +#ifdef CONFIG_SOC_PNX8550
> + write_c0_wired(11);
> +#else
> write_c0_wired(0);
> +#endif
11 wired entries sounds excessive to me. Is it really necessary to
kill that much performance?
Thiemo
