add blackfin cache and traps handling

1 files changed, 402 insertions, 0 deletions

diff --git a/arch/blackfin/lib/flush.S b/arch/blackfin/lib/flush.S
new file mode 100644
index 0000000000..62aa496986
--- /dev/null
+++ b/arch/blackfin/lib/flush.S
@@ -0,0 +1,402 @@
+/* Copyright (C) 2003 Analog Devices, Inc. All Rights Reserved.
+ * Copyright (C) 2004 LG SOft India. All Rights Reserved.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.
+ *
+ * Blackfin BF533/2.6 support : LG Soft India
+ */
+#define ASSEMBLY
+
+#include <asm/linkage.h>
+#include <asm/cplb.h>
+#include <asm/blackfin.h>
+
+.text
+
+/* This is an external function being called by the user
+ * application through __flush_cache_all. Currently this function
+ * serves the purpose of flushing all the pending writes in
+ * in the instruction cache.
+ */
+
+ENTRY(_flush_instruction_cache)
+	[--SP] = ( R7:6, P5:4 );
+	LINK 12;
+	SP += -12;
+	P5.H = (ICPLB_ADDR0 >> 16);
+	P5.L = (ICPLB_ADDR0 & 0xFFFF);
+	P4.H = (ICPLB_DATA0 >> 16);
+	P4.L = (ICPLB_DATA0 & 0xFFFF);
+	R7 = CPLB_VALID | CPLB_L1_CHBL;
+	R6 = 16;
+inext:	R0 = [P5++];
+	R1 = [P4++];
+	[--SP] =  RETS;
+	CALL icplb_flush;	/* R0 = page, R1 = data*/
+	RETS = [SP++];
+iskip:	R6 += -1;
+	CC = R6;
+	IF CC JUMP inext;
+	SSYNC;
+	SP += 12;
+	UNLINK;
+	( R7:6, P5:4 ) = [SP++];
+	RTS;
+
+/* This is an internal function to flush all pending
+ * writes in the cache associated with a particular ICPLB.
+ *
+ * R0 -  page's start address
+ * R1 -  CPLB's data field.
+ */
+
+.align 2
+ENTRY(icplb_flush)
+	[--SP] = ( R7:0, P5:0 );
+	[--SP] = LC0;
+	[--SP] = LT0;
+	[--SP] = LB0;
+	[--SP] = LC1;
+	[--SP] = LT1;
+	[--SP] = LB1;
+
+	/* If it's a 1K or 4K page, then it's quickest to
+	 * just systematically flush all the addresses in
+	 * the page, regardless of whether they're in the
+	 * cache, or dirty. If it's a 1M or 4M page, there
+	 * are too many addresses, and we have to search the
+	 * cache for lines corresponding to the page.
+	 */
+
+	CC = BITTST(R1, 17);	/* 1MB or 4MB */
+	IF !CC JUMP iflush_whole_page;
+
+	/* We're only interested in the page's size, so extract
+	 * this from the CPLB (bits 17:16), and scale to give an
+	 * offset into the page_size and page_prefix tables.
+	 */
+
+	R1 <<= 14;
+	R1 >>= 30;
+	R1 <<= 2;
+
+	/* We can also determine the sub-bank used, because this is
+	 * taken from bits 13:12 of the address.
+	 */
+
+	R3 = ((12<<8)|2);		/* Extraction pattern */
+	nop;				/*Anamoly 05000209*/
+	R4 = EXTRACT(R0, R3.L) (Z);	/* Extract bits*/
+	R3.H = R4.L << 0 ;		/* Save in extraction pattern for later deposit.*/
+
+
+	/* So:
+	 * R0 = Page start
+	 * R1 = Page length (actually, offset into size/prefix tables)
+	 * R3 = sub-bank deposit values
+  	 *
+	 * The cache has 2 Ways, and 64 sets, so we iterate through
+	 * the sets, accessing the tag for each Way, for our Bank and
+	 * sub-bank, looking for dirty, valid tags that match our
+	 * address prefix.
+	 */
+
+	P5.L = (ITEST_COMMAND & 0xFFFF);
+	P5.H = (ITEST_COMMAND >> 16);
+	P4.L = (ITEST_DATA0 & 0xFFFF);
+	P4.H = (ITEST_DATA0 >> 16);
+
+	P0.L = page_prefix_table;
+	P0.H = page_prefix_table;
+	P1 = R1;
+	R5 = 0;			/* Set counter*/
+	P0 = P1 + P0;
+	R4 = [P0];		/* This is the address prefix*/
+
+	/* We're reading (bit 1==0) the tag (bit 2==0), and we
+	 * don't care about which double-word, since we're only
+	 * fetching tags, so we only have to set Set, Bank,
+	 * Sub-bank and Way.
+	 */
+
+	P2 = 4;
+	LSETUP (ifs1, ife1) LC1 = P2;
+ifs1:	P0 = 32;		/* iterate over all sets*/
+	LSETUP (ifs0, ife0) LC0 = P0;
+ifs0:	R6 = R5 << 5;		/* Combine set*/
+	R6.H = R3.H << 0 ;	/* and sub-bank*/
+	[P5] = R6;		/* Issue Command*/
+	SSYNC;			/* CSYNC will not work here :(*/
+	R7 = [P4];		/* and read Tag.*/
+	CC = BITTST(R7, 0);	/* Check if valid*/
+	IF !CC JUMP ifskip;	/* and skip if not.*/
+
+	/* Compare against the page address. First, plant bits 13:12
+	 * into the tag, since those aren't part of the returned data.
+	 */
+
+	R7 = DEPOSIT(R7, R3);	/* set 13:12*/
+	R1 = R7 & R4;		/* Mask off lower bits*/
+	CC = R1 == R0;		/* Compare against page start.*/
+	IF !CC JUMP ifskip;	/* Skip it if it doesn't match.*/
+
+	/* Tag address matches against page, so this is an entry
+	 * we must flush.
+	 */
+
+	R7 >>= 10;		/* Mask off the non-address bits*/
+	R7 <<= 10;
+	P3 = R7;
+	IFLUSH [P3];		/* And flush the entry*/
+ifskip:
+ife0:	R5 += 1;		/* Advance to next Set*/
+ife1:	NOP;
+
+ifinished:
+	SSYNC;			/* Ensure the data gets out to mem.*/
+
+	/*Finished. Restore context.*/
+	LB1 = [SP++];
+	LT1 = [SP++];
+	LC1 = [SP++];
+	LB0 = [SP++];
+	LT0 = [SP++];
+	LC0 = [SP++];
+	( R7:0, P5:0 ) = [SP++];
+	RTS;
+
+iflush_whole_page:
+	/* It's a 1K or 4K page, so quicker to just flush the
+	 * entire page.
+	 */
+
+	P1 = 32;		/* For 1K pages*/
+	P2 = P1 << 2;		/* For 4K pages*/
+	P0 = R0;		/* Start of page*/
+	CC = BITTST(R1, 16);	/* Whether 1K or 4K*/
+	IF CC P1 = P2;
+	P1 += -1;		/* Unroll one iteration*/
+	SSYNC;
+	IFLUSH [P0++];		/* because CSYNC can't end loops.*/
+	LSETUP (isall, ieall) LC0 = P1;
+isall:IFLUSH [P0++];
+ieall: NOP;
+	SSYNC;
+	JUMP ifinished;
+
+/* This is an external function being called by the user
+ * application through __flush_cache_all. Currently this function
+ * serves the purpose of flushing all the pending writes in
+ * in the data cache.
+ */
+
+ENTRY(_flush_data_cache)
+	[--SP] = ( R7:6, P5:4 );
+	LINK 12;
+	SP += -12;
+	P5.H = (DCPLB_ADDR0 >> 16);
+	P5.L = (DCPLB_ADDR0 & 0xFFFF);
+	P4.H = (DCPLB_DATA0 >> 16);
+	P4.L = (DCPLB_DATA0 & 0xFFFF);
+	R7 = CPLB_VALID | CPLB_L1_CHBL | CPLB_DIRTY (Z);
+	R6 = 16;
+next:	R0 = [P5++];
+	R1 = [P4++];
+	CC = BITTST(R1, 14);	/* Is it write-through?*/
+	IF CC JUMP skip;	/* If so, ignore it.*/
+	R2 = R1 & R7;		/* Is it a dirty, cached page?*/
+	CC = R2;
+	IF !CC JUMP skip;	/* If not, ignore it.*/
+	[--SP] = RETS;
+	CALL dcplb_flush;	/* R0 = page, R1 = data*/
+	RETS = [SP++];
+skip:	R6 += -1;
+	CC = R6;
+	IF CC JUMP next;
+	SSYNC;
+	SP += 12;
+	UNLINK;
+	( R7:6, P5:4 ) = [SP++];
+	RTS;
+
+/* This is an internal function to flush all pending
+ * writes in the cache associated with a particular DCPLB.
+ *
+ * R0 -  page's start address
+ * R1 -  CPLB's data field.
+ */
+
+.align 2
+ENTRY(dcplb_flush)
+	[--SP] = ( R7:0, P5:0 );
+	[--SP] = LC0;
+	[--SP] = LT0;
+	[--SP] = LB0;
+	[--SP] = LC1;
+	[--SP] = LT1;
+	[--SP] = LB1;
+
+	/* If it's a 1K or 4K page, then it's quickest to
+	 * just systematically flush all the addresses in
+	 * the page, regardless of whether they're in the
+	 * cache, or dirty. If it's a 1M or 4M page, there
+	 * are too many addresses, and we have to search the
+	 * cache for lines corresponding to the page.
+	 */
+
+	CC = BITTST(R1, 17);	/* 1MB or 4MB */
+	IF !CC JUMP dflush_whole_page;
+
+	/* We're only interested in the page's size, so extract
+	 * this from the CPLB (bits 17:16), and scale to give an
+	 * offset into the page_size and page_prefix tables.
+	 */
+
+	R1 <<= 14;
+	R1 >>= 30;
+	R1 <<= 2;
+
+	/* The page could be mapped into Bank A or Bank B, depending
+	 * on (a) whether both banks are configured as cache, and
+	 * (b) on whether address bit A[x] is set. x is determined
+	 * by DCBS in DMEM_CONTROL
+	 */
+
+	R2 = 0;			/* Default to Bank A (Bank B would be 1)*/
+
+	P0.L = (DMEM_CONTROL & 0xFFFF);
+	P0.H = (DMEM_CONTROL >> 16);
+
+	R3 = [P0];		/* If Bank B is not enabled as cache*/
+	CC = BITTST(R3, 2);	/* then Bank A is our only option.*/
+	IF CC JUMP bank_chosen;
+
+	R4 = 1<<14;		/* If DCBS==0, use A[14].*/
+	R5 = R4 << 7;		/* If DCBS==1, use A[23];*/
+	CC = BITTST(R3, 4);
+	IF CC R4 = R5;		/* R4 now has either bit 14 or bit 23 set.*/
+	R5 = R0 & R4;		/* Use it to test the Page address*/
+	CC = R5;		/* and if that bit is set, we use Bank B,*/
+	R2 = CC;		/* else we use Bank A.*/
+	R2 <<= 23;		/* The Bank selection's at posn 23.*/
+
+bank_chosen:
+
+	/* We can also determine the sub-bank used, because this is
+	 * taken from bits 13:12 of the address.
+	 */
+
+	R3 = ((12<<8)|2);		/* Extraction pattern */
+	nop;				/*Anamoly 05000209*/
+	R4 = EXTRACT(R0, R3.L) (Z);	/* Extract bits*/
+	R3.H = R4.L << 0 ;		/* Save in extraction pattern for later deposit.*/
+
+	/* So:
+	 * R0 = Page start
+	 * R1 = Page length (actually, offset into size/prefix tables)
+	 * R2 = Bank select mask
+	 * R3 = sub-bank deposit values
+  	 *
+	 * The cache has 2 Ways, and 64 sets, so we iterate through
+	 * the sets, accessing the tag for each Way, for our Bank and
+	 * sub-bank, looking for dirty, valid tags that match our
+	 * address prefix.
+	 */
+
+	P5.L = (DTEST_COMMAND & 0xFFFF);
+	P5.H = (DTEST_COMMAND >> 16);
+	P4.L = (DTEST_DATA0 & 0xFFFF);
+	P4.H = (DTEST_DATA0 >> 16);
+
+	P0.L = page_prefix_table;
+	P0.H = page_prefix_table;
+	P1 = R1;
+	R5 = 0;			/* Set counter*/
+	P0 = P1 + P0;
+	R4 = [P0];		/* This is the address prefix*/
+
+
+	/* We're reading (bit 1==0) the tag (bit 2==0), and we
+	 * don't care about which double-word, since we're only
+	 * fetching tags, so we only have to set Set, Bank,
+	 * Sub-bank and Way.
+	 */
+
+	P2 = 2;
+	LSETUP (fs1, fe1) LC1 = P2;
+fs1:	P0 = 64;		/* iterate over all sets*/
+	LSETUP (fs0, fe0) LC0 = P0;
+fs0:	R6 = R5 << 5;		/* Combine set*/
+	R6.H = R3.H << 0 ;	/* and sub-bank*/
+	R6 = R6 | R2;		/* and Bank. Leave Way==0 at first.*/
+	BITSET(R6,14);
+	[P5] = R6;		/* Issue Command*/
+	SSYNC;
+	R7 = [P4];		/* and read Tag.*/
+	CC = BITTST(R7, 0);	/* Check if valid*/
+	IF !CC JUMP fskip;	/* and skip if not.*/
+	CC = BITTST(R7, 1);	/* Check if dirty*/
+	IF !CC JUMP fskip;	/* and skip if not.*/
+
+	/* Compare against the page address. First, plant bits 13:12
+	 * into the tag, since those aren't part of the returned data.
+	 */
+
+	R7 = DEPOSIT(R7, R3);	/* set 13:12*/
+	R1 = R7 & R4;		/* Mask off lower bits*/
+	CC = R1 == R0;		/* Compare against page start.*/
+	IF !CC JUMP fskip;	/* Skip it if it doesn't match.*/
+
+	/* Tag address matches against page, so this is an entry
+	 * we must flush.
+	 */
+
+	R7 >>= 10;		/* Mask off the non-address bits*/
+	R7 <<= 10;
+	P3 = R7;
+	SSYNC;
+	FLUSHINV [P3];		/* And flush the entry*/
+fskip:
+fe0:	R5 += 1;		/* Advance to next Set*/
+fe1:	BITSET(R2, 26);		/* Go to next Way.*/
+
+dfinished:
+	SSYNC;			/* Ensure the data gets out to mem.*/
+
+	/*Finished. Restore context.*/
+	LB1 = [SP++];
+	LT1 = [SP++];
+	LC1 = [SP++];
+	LB0 = [SP++];
+	LT0 = [SP++];
+	LC0 = [SP++];
+	( R7:0, P5:0 ) = [SP++];
+	RTS;
+
+dflush_whole_page:
+
+	/* It's a 1K or 4K page, so quicker to just flush the
+	 * entire page.
+	 */
+
+	P1 = 32;		/* For 1K pages*/
+	P2 = P1 << 2;		/* For 4K pages*/
+	P0 = R0;		/* Start of page*/
+	CC = BITTST(R1, 16);	/* Whether 1K or 4K*/
+	IF CC P1 = P2;
+	P1 += -1;		/* Unroll one iteration*/
+    SSYNC;
+	FLUSHINV [P0++];	/* because CSYNC can't end loops.*/
+	LSETUP (eall, eall) LC0 = P1;
+eall:	FLUSHINV [P0++];
+	SSYNC;
+	JUMP dfinished;
+
+.align 4;
+page_prefix_table:
+.byte4 	0xFFFFFC00;	/* 1K */
+.byte4	0xFFFFF000;	/* 4K */
+.byte4	0xFFF00000;	/* 1M */
+.byte4	0xFFC00000;	/* 4M */
+.page_prefix_table.end: