arch/powerpc/kernel/85xx_entry_mapping.S

Source file repositories/reference/linux-study-clean/arch/powerpc/kernel/85xx_entry_mapping.S

File Facts

System
Linux kernel
Corpus path
arch/powerpc/kernel/85xx_entry_mapping.S
Extension
.S
Size
5509 bytes
Lines
231
Domain
Architecture Layer
Bucket
arch/powerpc
Inferred role
Architecture Layer: arch/powerpc
Status
atlas-only

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

bcl	20,31,$+4				/* Find our address */
invstr:	mflr	r6				/* Make it accessible */
	mfmsr	r7
	rlwinm	r4,r7,27,31,31			/* extract MSR[IS] */
	mfspr	r7, SPRN_PID0
	slwi	r7,r7,16
	or	r7,r7,r4
	mtspr	SPRN_MAS6,r7
	tlbsx	0,r6				/* search MSR[IS], SPID=PID0 */
	mfspr	r7,SPRN_MAS1
	andis.	r7,r7,MAS1_VALID@h
	bne	match_TLB

	mfspr	r7,SPRN_MMUCFG
	rlwinm	r7,r7,21,28,31			/* extract MMUCFG[NPIDS] */
	cmpwi	r7,3
	bne	match_TLB			/* skip if NPIDS != 3 */

	mfspr	r7,SPRN_PID1
	slwi	r7,r7,16
	or	r7,r7,r4
	mtspr	SPRN_MAS6,r7
	tlbsx	0,r6				/* search MSR[IS], SPID=PID1 */
	mfspr	r7,SPRN_MAS1
	andis.	r7,r7,MAS1_VALID@h
	bne	match_TLB
	mfspr	r7, SPRN_PID2
	slwi	r7,r7,16
	or	r7,r7,r4
	mtspr	SPRN_MAS6,r7
	tlbsx	0,r6				/* Fall through, we had to match */

match_TLB:
	mfspr	r7,SPRN_MAS0
	rlwinm	r3,r7,16,20,31			/* Extract MAS0(Entry) */

	mfspr	r7,SPRN_MAS1			/* Insure IPROT set */
	oris	r7,r7,MAS1_IPROT@h
	mtspr	SPRN_MAS1,r7
	tlbwe

/* 2. Invalidate all entries except the entry we're executing in */
	mfspr	r9,SPRN_TLB1CFG
	andi.	r9,r9,0xfff
	li	r6,0				/* Set Entry counter to 0 */
1:	lis	r7,0x1000			/* Set MAS0(TLBSEL) = 1 */
	rlwimi	r7,r6,16,4,15			/* Setup MAS0 = TLBSEL | ESEL(r6) */
	mtspr	SPRN_MAS0,r7
	tlbre
	mfspr	r7,SPRN_MAS1
	rlwinm	r7,r7,0,2,31			/* Clear MAS1 Valid and IPROT */
	cmpw	r3,r6
	beq	skpinv				/* Dont update the current execution TLB */
	mtspr	SPRN_MAS1,r7
	tlbwe
	isync
skpinv:	addi	r6,r6,1				/* Increment */
	cmpw	r6,r9				/* Are we done? */
	bne	1b				/* If not, repeat */

	/* Invalidate TLB0 */
	li	r6,0x04
	tlbivax 0,r6
	TLBSYNC
	/* Invalidate TLB1 */
	li	r6,0x0c
	tlbivax 0,r6
	TLBSYNC

/* 3. Setup a temp mapping and jump to it */

Annotation

Implementation Notes