powerpc: Merge enough to start building in arch/powerpc.

This creates the directory structure under arch/powerpc and a bunch
of Kconfig files.  It does a first-cut merge of arch/powerpc/mm,
arch/powerpc/lib and arch/powerpc/platforms/powermac.  This is enough
to build a 32-bit powermac kernel with ARCH=powerpc.

For now we are getting some unmerged files from arch/ppc/kernel and
arch/ppc/syslib, or arch/ppc64/kernel.  This makes some minor changes
to files in those directories and files outside arch/powerpc.

The boot directory is still not merged.  That's going to be interesting.

Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 296 insertions, 0 deletions

diff --git a/arch/powerpc/mm/ppc_mmu.c b/arch/powerpc/mm/ppc_mmu.c
new file mode 100644
index 00000000000..9a381ed5eb2
--- /dev/null
+++ b/arch/powerpc/mm/ppc_mmu.c
@@ -0,0 +1,296 @@
+/*
+ * This file contains the routines for handling the MMU on those
+ * PowerPC implementations where the MMU substantially follows the
+ * architecture specification.  This includes the 6xx, 7xx, 7xxx,
+ * 8260, and POWER3 implementations but excludes the 8xx and 4xx.
+ *  -- paulus
+ *
+ *  Derived from arch/ppc/mm/init.c:
+ *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *
+ *  Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
+ *  and Cort Dougan (PReP) (cort@cs.nmt.edu)
+ *    Copyright (C) 1996 Paul Mackerras
+ *  Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk).
+ *
+ *  Derived from "arch/i386/mm/init.c"
+ *    Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
+ *
+ *  This program is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License
+ *  as published by the Free Software Foundation; either version
+ *  2 of the License, or (at your option) any later version.
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/init.h>
+#include <linux/highmem.h>
+
+#include <asm/prom.h>
+#include <asm/mmu.h>
+#include <asm/machdep.h>
+
+#include "mmu_decl.h"
+#include "mem_pieces.h"
+
+PTE *Hash, *Hash_end;
+unsigned long Hash_size, Hash_mask;
+unsigned long _SDR1;
+
+union ubat {			/* BAT register values to be loaded */
+	BAT	bat;
+#ifdef CONFIG_PPC64BRIDGE
+	u64	word[2];
+#else
+	u32	word[2];
+#endif
+} BATS[4][2];			/* 4 pairs of IBAT, DBAT */
+
+struct batrange {		/* stores address ranges mapped by BATs */
+	unsigned long start;
+	unsigned long limit;
+	unsigned long phys;
+} bat_addrs[4];
+
+/*
+ * Return PA for this VA if it is mapped by a BAT, or 0
+ */
+unsigned long v_mapped_by_bats(unsigned long va)
+{
+	int b;
+	for (b = 0; b < 4; ++b)
+		if (va >= bat_addrs[b].start && va < bat_addrs[b].limit)
+			return bat_addrs[b].phys + (va - bat_addrs[b].start);
+	return 0;
+}
+
+/*
+ * Return VA for a given PA or 0 if not mapped
+ */
+unsigned long p_mapped_by_bats(unsigned long pa)
+{
+	int b;
+	for (b = 0; b < 4; ++b)
+		if (pa >= bat_addrs[b].phys
+	    	    && pa < (bat_addrs[b].limit-bat_addrs[b].start)
+		              +bat_addrs[b].phys)
+			return bat_addrs[b].start+(pa-bat_addrs[b].phys);
+	return 0;
+}
+
+unsigned long __init mmu_mapin_ram(void)
+{
+#ifdef CONFIG_POWER4
+	return 0;
+#else
+	unsigned long tot, bl, done;
+	unsigned long max_size = (256<<20);
+	unsigned long align;
+
+	if (__map_without_bats)
+		return 0;
+
+	/* Set up BAT2 and if necessary BAT3 to cover RAM. */
+
+	/* Make sure we don't map a block larger than the
+	   smallest alignment of the physical address. */
+	/* alignment of PPC_MEMSTART */
+	align = ~(PPC_MEMSTART-1) & PPC_MEMSTART;
+	/* set BAT block size to MIN(max_size, align) */
+	if (align && align < max_size)
+		max_size = align;
+
+	tot = total_lowmem;
+	for (bl = 128<<10; bl < max_size; bl <<= 1) {
+		if (bl * 2 > tot)
+			break;
+	}
+
+	setbat(2, KERNELBASE, PPC_MEMSTART, bl, _PAGE_RAM);
+	done = (unsigned long)bat_addrs[2].limit - KERNELBASE + 1;
+	if ((done < tot) && !bat_addrs[3].limit) {
+		/* use BAT3 to cover a bit more */
+		tot -= done;
+		for (bl = 128<<10; bl < max_size; bl <<= 1)
+			if (bl * 2 > tot)
+				break;
+		setbat(3, KERNELBASE+done, PPC_MEMSTART+done, bl, _PAGE_RAM);
+		done = (unsigned long)bat_addrs[3].limit - KERNELBASE + 1;
+	}
+
+	return done;
+#endif
+}
+
+/*
+ * Set up one of the I/D BAT (block address translation) register pairs.
+ * The parameters are not checked; in particular size must be a power
+ * of 2 between 128k and 256M.
+ */
+void __init setbat(int index, unsigned long virt, unsigned long phys,
+		   unsigned int size, int flags)
+{
+	unsigned int bl;
+	int wimgxpp;
+	union ubat *bat = BATS[index];
+
+	if (((flags & _PAGE_NO_CACHE) == 0) &&
+	    cpu_has_feature(CPU_FTR_NEED_COHERENT))
+		flags |= _PAGE_COHERENT;
+
+	bl = (size >> 17) - 1;
+	if (PVR_VER(mfspr(SPRN_PVR)) != 1) {
+		/* 603, 604, etc. */
+		/* Do DBAT first */
+		wimgxpp = flags & (_PAGE_WRITETHRU | _PAGE_NO_CACHE
+				   | _PAGE_COHERENT | _PAGE_GUARDED);
+		wimgxpp |= (flags & _PAGE_RW)? BPP_RW: BPP_RX;
+		bat[1].word[0] = virt | (bl << 2) | 2; /* Vs=1, Vp=0 */
+		bat[1].word[1] = phys | wimgxpp;
+#ifndef CONFIG_KGDB /* want user access for breakpoints */
+		if (flags & _PAGE_USER)
+#endif
+			bat[1].bat.batu.vp = 1;
+		if (flags & _PAGE_GUARDED) {
+			/* G bit must be zero in IBATs */
+			bat[0].word[0] = bat[0].word[1] = 0;
+		} else {
+			/* make IBAT same as DBAT */
+			bat[0] = bat[1];
+		}
+	} else {
+		/* 601 cpu */
+		if (bl > BL_8M)
+			bl = BL_8M;
+		wimgxpp = flags & (_PAGE_WRITETHRU | _PAGE_NO_CACHE
+				   | _PAGE_COHERENT);
+		wimgxpp |= (flags & _PAGE_RW)?
+			((flags & _PAGE_USER)? PP_RWRW: PP_RWXX): PP_RXRX;
+		bat->word[0] = virt | wimgxpp | 4;	/* Ks=0, Ku=1 */
+		bat->word[1] = phys | bl | 0x40;	/* V=1 */
+	}
+
+	bat_addrs[index].start = virt;
+	bat_addrs[index].limit = virt + ((bl + 1) << 17) - 1;
+	bat_addrs[index].phys = phys;
+}
+
+/*
+ * Initialize the hash table and patch the instructions in hashtable.S.
+ */
+void __init MMU_init_hw(void)
+{
+	unsigned int hmask, mb, mb2;
+	unsigned int n_hpteg, lg_n_hpteg;
+
+	extern unsigned int hash_page_patch_A[];
+	extern unsigned int hash_page_patch_B[], hash_page_patch_C[];
+	extern unsigned int hash_page[];
+	extern unsigned int flush_hash_patch_A[], flush_hash_patch_B[];
+
+	if (!cpu_has_feature(CPU_FTR_HPTE_TABLE)) {
+		/*
+		 * Put a blr (procedure return) instruction at the
+		 * start of hash_page, since we can still get DSI
+		 * exceptions on a 603.
+		 */
+		hash_page[0] = 0x4e800020;
+		flush_icache_range((unsigned long) &hash_page[0],
+				   (unsigned long) &hash_page[1]);
+		return;
+	}
+
+	if ( ppc_md.progress ) ppc_md.progress("hash:enter", 0x105);
+
+#ifdef CONFIG_PPC64BRIDGE
+#define LG_HPTEG_SIZE	7		/* 128 bytes per HPTEG */
+#define SDR1_LOW_BITS	(lg_n_hpteg - 11)
+#define MIN_N_HPTEG	2048		/* min 256kB hash table */
+#else
+#define LG_HPTEG_SIZE	6		/* 64 bytes per HPTEG */
+#define SDR1_LOW_BITS	((n_hpteg - 1) >> 10)
+#define MIN_N_HPTEG	1024		/* min 64kB hash table */
+#endif
+
+#ifdef CONFIG_POWER4
+	/* The hash table has already been allocated and initialized
+	   in prom.c */
+	n_hpteg = Hash_size >> LG_HPTEG_SIZE;
+	lg_n_hpteg = __ilog2(n_hpteg);
+
+	/* Remove the hash table from the available memory */
+	if (Hash)
+		reserve_phys_mem(__pa(Hash), Hash_size);
+
+#else /* CONFIG_POWER4 */
+	/*
+	 * Allow 1 HPTE (1/8 HPTEG) for each page of memory.
+	 * This is less than the recommended amount, but then
+	 * Linux ain't AIX.
+	 */
+	n_hpteg = total_memory / (PAGE_SIZE * 8);
+	if (n_hpteg < MIN_N_HPTEG)
+		n_hpteg = MIN_N_HPTEG;
+	lg_n_hpteg = __ilog2(n_hpteg);
+	if (n_hpteg & (n_hpteg - 1)) {
+		++lg_n_hpteg;		/* round up if not power of 2 */
+		n_hpteg = 1 << lg_n_hpteg;
+	}
+	Hash_size = n_hpteg << LG_HPTEG_SIZE;
+
+	/*
+	 * Find some memory for the hash table.
+	 */
+	if ( ppc_md.progress ) ppc_md.progress("hash:find piece", 0x322);
+	Hash = mem_pieces_find(Hash_size, Hash_size);
+	cacheable_memzero(Hash, Hash_size);
+	_SDR1 = __pa(Hash) | SDR1_LOW_BITS;
+#endif /* CONFIG_POWER4 */
+
+	Hash_end = (PTE *) ((unsigned long)Hash + Hash_size);
+
+	printk("Total memory = %ldMB; using %ldkB for hash table (at %p)\n",
+	       total_memory >> 20, Hash_size >> 10, Hash);
+
+
+	/*
+	 * Patch up the instructions in hashtable.S:create_hpte
+	 */
+	if ( ppc_md.progress ) ppc_md.progress("hash:patch", 0x345);
+	Hash_mask = n_hpteg - 1;
+	hmask = Hash_mask >> (16 - LG_HPTEG_SIZE);
+	mb2 = mb = 32 - LG_HPTEG_SIZE - lg_n_hpteg;
+	if (lg_n_hpteg > 16)
+		mb2 = 16 - LG_HPTEG_SIZE;
+
+	hash_page_patch_A[0] = (hash_page_patch_A[0] & ~0xffff)
+		| ((unsigned int)(Hash) >> 16);
+	hash_page_patch_A[1] = (hash_page_patch_A[1] & ~0x7c0) | (mb << 6);
+	hash_page_patch_A[2] = (hash_page_patch_A[2] & ~0x7c0) | (mb2 << 6);
+	hash_page_patch_B[0] = (hash_page_patch_B[0] & ~0xffff) | hmask;
+	hash_page_patch_C[0] = (hash_page_patch_C[0] & ~0xffff) | hmask;
+
+	/*
+	 * Ensure that the locations we've patched have been written
+	 * out from the data cache and invalidated in the instruction
+	 * cache, on those machines with split caches.
+	 */
+	flush_icache_range((unsigned long) &hash_page_patch_A[0],
+			   (unsigned long) &hash_page_patch_C[1]);
+
+	/*
+	 * Patch up the instructions in hashtable.S:flush_hash_page
+	 */
+	flush_hash_patch_A[0] = (flush_hash_patch_A[0] & ~0xffff)
+		| ((unsigned int)(Hash) >> 16);
+	flush_hash_patch_A[1] = (flush_hash_patch_A[1] & ~0x7c0) | (mb << 6);
+	flush_hash_patch_A[2] = (flush_hash_patch_A[2] & ~0x7c0) | (mb2 << 6);
+	flush_hash_patch_B[0] = (flush_hash_patch_B[0] & ~0xffff) | hmask;
+	flush_icache_range((unsigned long) &flush_hash_patch_A[0],
+			   (unsigned long) &flush_hash_patch_B[1]);
+
+	if ( ppc_md.progress ) ppc_md.progress("hash:done", 0x205);
+}