Re: [PATCH 5/10 v2] Add 8641 CPU and i8259 Setup
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: 2006-06-09 04:23:21
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--- a/arch/powerpc/kernel/head_32.S +++ b/arch/powerpc/kernel/head_32.S@@ -224,6 +224,10 @@ turn_on_mmu: li r3,1 /* MTX only has 1 cpu */ .globl __secondary_hold __secondary_hold: +#ifdef CONFIG_PPC_86xx + /* get the cpu id */ + mfspr r3, SPRN_PIR +#endif
The above is wrong, it prevents using the same kernel image on another platform. If you need a separate hold loop, then go for it but don't change the existing one in a non-compatible way. Alternatively, you can do like powermac, that is have several "entrypoints" to the same hold loop providing different CPU IDs.
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/* tell the master we're here */ stw r3,__secondary_hold_acknowledge@l(0) #ifdef CONFIG_SMP@@ -348,6 +352,16 @@ #define EXC_XFER_EE_LITE(n, hdlr) \ #if defined(CONFIG_GEMINI) && defined(CONFIG_SMP) . = 0x100 b __secondary_start_gemini +#endif +/* we need to ensure that the address translation is disabled */ +#if defined(CONFIG_PPC_86xx) && defined(CONFIG_SMP) + . = 0x100 + mfmsr r3 + andi. r0, r3, (MSR_IR | MSR_DR) + andc r3, r3, r0 + mtmsr r3 + isync + b __secondary_hold #else EXCEPTION(0x100, Reset, unknown_exception, EXC_XFER_STD) #endif
Same comment above... #ifdef is bad. You are entering from 0x100 with address translation not disabled ? How is that possible ? If it's your firmware, then fix it :) If not possible, then have a real good explanation why and how you end up in 0x100 that way. At worse, do like pmac does and "patch" the 0x100 vector to point to some machine specific code dynamically at runtime.
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@@ -1019,6 +1033,7 @@ #endif /* CONFIG_6xx */ stw r0,0(r3) /* load up the MMU */ + bl clear_bats bl load_up_mmu
Why do you need to call clear_bats here ? load_up_mmu should load BATs. If it doesn't handle the high BATs, then fix it :)
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/* ptr to phys current thread */diff --git a/arch/powerpc/sysdev/i8259.c b/arch/powerpc/sysdev/i8259.c index b7ac32f..9b755e1 100644 --- a/arch/powerpc/sysdev/i8259.c +++ b/arch/powerpc/sysdev/i8259.c@@ -201,6 +201,11 @@ void __init i8259_init(unsigned long int outb(0x0B, 0x20); outb(0x0B, 0xA0); +#ifdef CONFIG_I8259_LEVEL_TRIGGER + outb(0xfa, 0x4d0); /* level triggered */ + outb(0xde, 0x4d1); +#endif
Another change that breaks multiplatform... Can you explain precisely what you are trying to acheive here ? If necessary, we can add an argument to i8259_init. Or you could do the above in your platform code ... though I agree it would be a bit ugly :)
/* Mask all interrupts */ outb(cached_A1, 0xA1); outb(cached_21, 0x21);