Commit 57d7909e authored by David Gibson's avatar David Gibson Committed by Paul Mackerras
Browse files

[POWERPC] Revise PPC44x MMU code for arch/powerpc 



This patch takes the definitions for the PPC44x MMU (a software loaded
TLB) from asm-ppc/mmu.h, cleans them up of things no longer necessary
in arch/powerpc and puts them in a new asm-powerpc/mmu_44x.h file.  It
also substantially simplifies arch/powerpc/mm/44x_mmu.c and makes a
couple of small fixes necessary for the 44x MMU code to build and work
properly in arch/powerpc.

Signed-off-by: default avatarDavid Gibson <david@gibson.dropbear.id.au>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
parent c3e8011a

arch/powerpc/kernel/head_44x.S

+2 −2
Original line number Diff line number Diff line
@@ -120,8 +120,8 @@ skpinv: addi r4,r4,1 /* Increment */ 
 * Configure and load pinned entry into TLB slot 63.

 */



	lis	r3,KERNELBASE@h		/* Load the kernel virtual address */

	ori	r3,r3,KERNELBASE@l

	lis	r3,PAGE_OFFSET@h

	ori	r3,r3,PAGE_OFFSET@l



	/* Kernel is at the base of RAM */

	li r4, 0			/* Load the kernel physical address */

arch/powerpc/mm/44x_mmu.c

+19 −63
Original line number Diff line number Diff line
@@ -24,73 +24,38 @@ 
 *

 */



#include <linux/signal.h>

#include <linux/sched.h>

#include <linux/kernel.h>

#include <linux/errno.h>

#include <linux/string.h>

#include <linux/types.h>

#include <linux/ptrace.h>

#include <linux/mman.h>

#include <linux/mm.h>

#include <linux/swap.h>

#include <linux/stddef.h>

#include <linux/vmalloc.h>

#include <linux/init.h>

#include <linux/delay.h>

#include <linux/highmem.h>



#include <asm/pgalloc.h>

#include <asm/prom.h>

#include <asm/io.h>

#include <asm/mmu_context.h>

#include <asm/pgtable.h>

#include <asm/mmu.h>

#include <asm/uaccess.h>

#include <asm/smp.h>

#include <asm/bootx.h>

#include <asm/machdep.h>

#include <asm/setup.h>

#include <asm/system.h>

#include <asm/page.h>



#include "mmu_decl.h"



extern char etext[], _stext[];



/* Used by the 44x TLB replacement exception handler.

 * Just needed it declared someplace.

 */

unsigned int tlb_44x_index = 0;

unsigned int tlb_44x_hwater = 62;

unsigned int tlb_44x_index; /* = 0 */

unsigned int tlb_44x_hwater = PPC44x_TLB_SIZE - 1 - PPC44x_EARLY_TLBS;



/*

 * "Pins" a 256MB TLB entry in AS0 for kernel lowmem

 */

static void __init

ppc44x_pin_tlb(int slot, unsigned int virt, unsigned int phys)

static void __init ppc44x_pin_tlb(unsigned int virt, unsigned int phys)

{

	unsigned long attrib = 0;



	__asm__ __volatile__("\

	clrrwi	%2,%2,10\n\

	ori	%2,%2,%4\n\

	clrrwi	%1,%1,10\n\

	li	%0,0\n\

	ori	%0,%0,%5\n\

	tlbwe	%2,%3,%6\n\

	tlbwe	%1,%3,%7\n\

	tlbwe	%0,%3,%8"

	__asm__ __volatile__(

		"tlbwe	%2,%3,%4\n"

		"tlbwe	%1,%3,%5\n"

		"tlbwe	%0,%3,%6\n"

	:

	: "r" (attrib), "r" (phys), "r" (virt), "r" (slot),

	  "i" (PPC44x_TLB_VALID | PPC44x_TLB_256M),

	  "i" (PPC44x_TLB_SW | PPC44x_TLB_SR | PPC44x_TLB_SX | PPC44x_TLB_G),

	: "r" (PPC44x_TLB_SW | PPC44x_TLB_SR | PPC44x_TLB_SX | PPC44x_TLB_G),

	  "r" (phys),

	  "r" (virt | PPC44x_TLB_VALID | PPC44x_TLB_256M),

	  "r" (tlb_44x_hwater--), /* slot for this TLB entry */

	  "i" (PPC44x_TLB_PAGEID),

	  "i" (PPC44x_TLB_XLAT),

	  "i" (PPC44x_TLB_ATTRIB));

}



/*

 * MMU_init_hw does the chip-specific initialization of the MMU hardware.

 */

void __init MMU_init_hw(void)

{

	flush_instruction_cache();
@@ -98,22 +63,13 @@ void __init MMU_init_hw(void) 


unsigned long __init mmu_mapin_ram(void)

{

	unsigned int pinned_tlbs = 1;

	int i;



	/* Determine number of entries necessary to cover lowmem */

	pinned_tlbs = (unsigned int)

		(_ALIGN(total_lowmem, PPC_PIN_SIZE) >> PPC44x_PIN_SHIFT);

	unsigned long addr;



	/* Write upper watermark to save location */

	tlb_44x_hwater = PPC44x_LOW_SLOT - pinned_tlbs;



	/* If necessary, set additional pinned TLBs */

	if (pinned_tlbs > 1)

		for (i = (PPC44x_LOW_SLOT-(pinned_tlbs-1)); i < PPC44x_LOW_SLOT; i++) {

			unsigned int phys_addr = (PPC44x_LOW_SLOT-i) * PPC_PIN_SIZE;

			ppc44x_pin_tlb(i, phys_addr+PAGE_OFFSET, phys_addr);

		}

	/* Pin in enough TLBs to cover any lowmem not covered by the

	 * initial 256M mapping established in head_44x.S */

	for (addr = PPC_PIN_SIZE; addr < total_lowmem;

	     addr += PPC_PIN_SIZE)

		ppc44x_pin_tlb(addr + PAGE_OFFSET, addr);



	return total_lowmem;

}

arch/powerpc/mm/mmu_decl.h

+2 −1
Original line number Diff line number Diff line
@@ -40,7 +40,8 @@ extern int __map_without_bats; 
extern unsigned long ioremap_base;

extern unsigned int rtas_data, rtas_size;



extern PTE *Hash, *Hash_end;

struct _PTE;

extern struct _PTE *Hash, *Hash_end;

extern unsigned long Hash_size, Hash_mask;



extern unsigned int num_tlbcam_entries;

include/asm-powerpc/mmu-44x.h

0 → 100644
+72 −0
Original line number Diff line number Diff line 
#ifndef _ASM_POWERPC_MMU_44X_H_

#define _ASM_POWERPC_MMU_44X_H_

/*

 * PPC440 support

 */



#define PPC44x_MMUCR_TID	0x000000ff

#define PPC44x_MMUCR_STS	0x00010000



#define	PPC44x_TLB_PAGEID	0

#define	PPC44x_TLB_XLAT		1

#define	PPC44x_TLB_ATTRIB	2



/* Page identification fields */

#define PPC44x_TLB_EPN_MASK	0xfffffc00      /* Effective Page Number */

#define	PPC44x_TLB_VALID	0x00000200      /* Valid flag */

#define PPC44x_TLB_TS		0x00000100	/* Translation address space */

#define PPC44x_TLB_1K		0x00000000	/* Page sizes */

#define PPC44x_TLB_4K		0x00000010

#define PPC44x_TLB_16K		0x00000020

#define PPC44x_TLB_64K		0x00000030

#define PPC44x_TLB_256K		0x00000040

#define PPC44x_TLB_1M		0x00000050

#define PPC44x_TLB_16M		0x00000070

#define	PPC44x_TLB_256M		0x00000090



/* Translation fields */

#define PPC44x_TLB_RPN_MASK	0xfffffc00      /* Real Page Number */

#define	PPC44x_TLB_ERPN_MASK	0x0000000f



/* Storage attribute and access control fields */

#define PPC44x_TLB_ATTR_MASK	0x0000ff80

#define PPC44x_TLB_U0		0x00008000      /* User 0 */

#define PPC44x_TLB_U1		0x00004000      /* User 1 */

#define PPC44x_TLB_U2		0x00002000      /* User 2 */

#define PPC44x_TLB_U3		0x00001000      /* User 3 */

#define PPC44x_TLB_W		0x00000800      /* Caching is write-through */

#define PPC44x_TLB_I		0x00000400      /* Caching is inhibited */

#define PPC44x_TLB_M		0x00000200      /* Memory is coherent */

#define PPC44x_TLB_G		0x00000100      /* Memory is guarded */

#define PPC44x_TLB_E		0x00000080      /* Memory is guarded */



#define PPC44x_TLB_PERM_MASK	0x0000003f

#define PPC44x_TLB_UX		0x00000020      /* User execution */

#define PPC44x_TLB_UW		0x00000010      /* User write */

#define PPC44x_TLB_UR		0x00000008      /* User read */

#define PPC44x_TLB_SX		0x00000004      /* Super execution */

#define PPC44x_TLB_SW		0x00000002      /* Super write */

#define PPC44x_TLB_SR		0x00000001      /* Super read */



/* Number of TLB entries */

#define PPC44x_TLB_SIZE		64



#ifndef __ASSEMBLY__



typedef unsigned long long phys_addr_t;



extern phys_addr_t fixup_bigphys_addr(phys_addr_t, phys_addr_t);



typedef struct {

	unsigned long id;

	unsigned long vdso_base;

} mm_context_t;



#endif /* !__ASSEMBLY__ */



#define PPC44x_EARLY_TLBS	1



/* Size of the TLBs used for pinning in lowmem */

#define PPC_PIN_SIZE	(1 << 28)	/* 256M */



#endif /* _ASM_POWERPC_MMU_44X_H_ */

include/asm-powerpc/mmu.h

+5 −2
Original line number Diff line number Diff line
@@ -5,9 +5,12 @@ 
#ifdef CONFIG_PPC64

/* 64-bit classic hash table MMU */

#  include <asm/mmu-hash64.h>

#elif defined(CONFIG_44x)

/* 44x-style software loaded TLB */

#  include <asm/mmu-44x.h>

#else

/* 32-bit.  FIXME: split up the 32-bit MMU types, and revise for

 * arch/powerpc */

/* Other 32-bit.  FIXME: split up the other 32-bit MMU types, and

 * revise for arch/powerpc */

#  include <asm-ppc/mmu.h>

#endif