Martyn Welch wrote: > Scott Wood wrote: > >> On 05/28/2010 10:18 AM, Martyn Welch wrote: >> >>> The CPM early debug console hardcodes the BAT to cover the IMMR at >>> 0xf0000000. The IMMR (on the mpc8270 at the very least) can be set to a >>> number of locations with bootstrap configuration, which are outside the >>> hardcoded BAT configuration. >>> >>> This patch determines the correct location at which to configure a BAT >>> during the boot process from the supplied PPC_EARLY_DEBUG_CPM_ADDR. >>> >>> Signed-off-by: Martyn Welch<martyn.we...@ge.com> >>> --- >>> >>> arch/powerpc/kernel/head_32.S | 5 +++-- >>> arch/powerpc/sysdev/cpm_common.c | 4 +++- >>> 2 files changed, 6 insertions(+), 3 deletions(-) >>> >>> diff --git a/arch/powerpc/kernel/head_32.S >>> b/arch/powerpc/kernel/head_32.S >>> index e025e89..861cace 100644 >>> --- a/arch/powerpc/kernel/head_32.S >>> +++ b/arch/powerpc/kernel/head_32.S >>> @@ -1194,12 +1194,13 @@ setup_disp_bat: >>> #endif /* CONFIG_BOOTX_TEXT */ >>> >>> #ifdef CONFIG_PPC_EARLY_DEBUG_CPM >>> +#define PPC_EARLY_DEBUG_CPM_ADDR >>> ASM_CONST(CONFIG_PPC_EARLY_DEBUG_CPM_ADDR) >>> setup_cpm_bat: >>> - lis r8, 0xf000 >>> + lis r8, ppc_early_debug_cpm_a...@ha >>> ori r8, r8, 0x002a >>> mtspr SPRN_DBAT1L, r8 >>> >>> - lis r11, 0xf000 >>> + lis r11, ppc_early_debug_cpm_a...@ha >>> ori r11, r11, (BL_1M << 2) | 2 >>> mtspr SPRN_DBAT1U, r11 >>> >> Only the physical address should depend on where IMMR is. We should >> use fixmap instead of an arbitrary address for the effective address. >> There's a existing FIX_EARLY_DEBUG_BASE, but it's only 128 KiB so >> we'll have to either grow it, or map only a subset of IMMR. >> >> > > I think that's a more fundamental change to CPM early debug than I can > handle right now. > > >> Plus, CONFIG_PPC_EARLY_DEBUG_CPM_ADDR points to the TX descriptor, not >> to the beginning of IMMR, so you should mask off the lower 20 bits >> (the offset is probably less than 64K, and the BAT might just ignore >> the extra bits anyway, but why take chances?). >> >> > > I assume that an extra instruction "andi r8, r8, 0xfff0" after each > "lis" instruction would be what you are looking for? > > "andis" even.
Martyn > Martyn > > >> -Scott >> > > > -- Martyn Welch (Principal Software Engineer) | Registered in England and GE Intelligent Platforms | Wales (3828642) at 100 T +44(0)127322748 | Barbirolli Square, Manchester, E martyn.we...@ge.com | M2 3AB VAT:GB 927559189 _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
