+++ /dev/null
-/* flush.S - low level cache flushing routines
- * Copyright (C) 2003-2007 Analog Devices Inc.
- * Licensed under the GPL-2 or later.
- */
-
-#include <config.h>
-#include <asm/blackfin.h>
-#include <asm/cplb.h>
-#include <asm/mach-common/bits/mpu.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 data cache.
- */
-
-ENTRY(_flush_data_cache)
- [--SP] = ( R7:6, P5:4 );
- LINK 12;
- SP += -12;
- P5.H = HI(DCPLB_ADDR0);
- P5.L = LO(DCPLB_ADDR0);
- P4.H = HI(DCPLB_DATA0);
- P4.L = LO(DCPLB_DATA0);
- R7 = CPLB_VALID | CPLB_L1_CHBL | CPLB_DIRTY (Z);
- R6 = 16;
-.Lnext: R0 = [P5++];
- R1 = [P4++];
- CC = BITTST(R1, 14); /* Is it write-through?*/
- IF CC JUMP .Lskip; /* If so, ignore it.*/
- R2 = R1 & R7; /* Is it a dirty, cached page?*/
- CC = R2;
- IF !CC JUMP .Lskip; /* If not, ignore it.*/
- [--SP] = RETS;
- CALL _dcplb_flush; /* R0 = page, R1 = data*/
- RETS = [SP++];
-.Lskip: R6 += -1;
- CC = R6;
- IF CC JUMP .Lnext;
- SSYNC;
- SP += 12;
- UNLINK;
- ( R7:6, P5:4 ) = [SP++];
- RTS;
-ENDPROC(_flush_data_cache)
-
-/* 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 .Ldflush_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 = LO(DMEM_CONTROL);
- P0.H = HI(DMEM_CONTROL);
-
- R3 = [P0]; /* If Bank B is not enabled as cache*/
- CC = BITTST(R3, 2); /* then Bank A is our only option.*/
- IF CC JUMP .Lbank_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.*/
-
-.Lbank_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*/
- /* Save in extraction pattern for later deposit.*/
- R3.H = R4.L << 0;
-
- /* 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 = LO(DTEST_COMMAND);
- P5.H = HI(DTEST_COMMAND);
- P4.L = LO(DTEST_DATA0);
- P4.H = HI(DTEST_DATA0);
-
- 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 (.Lfs1, .Lfe1) LC1 = P2;
-.Lfs1: P0 = 64; /* iterate over all sets*/
- LSETUP (.Lfs0, .Lfe0) LC0 = P0;
-.Lfs0: 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 .Lfskip; /* and skip if not.*/
- CC = BITTST(R7, 1); /* Check if dirty*/
- IF !CC JUMP .Lfskip; /* 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 .Lfskip; /* 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*/
-.Lfskip:
-.Lfe0: R5 += 1; /* Advance to next Set*/
-.Lfe1: BITSET(R2, 26); /* Go to next Way.*/
-
-.Ldfinished:
- 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;
-
-.Ldflush_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 (.Leall, .Leall) LC0 = P1;
-.Leall: FLUSHINV [P0++];
- SSYNC;
- JUMP .Ldfinished;
-ENDPROC(_dcplb_flush)
-
-.align 4;
-page_prefix_table:
-.byte4 0xFFFFFC00; /* 1K */
-.byte4 0xFFFFF000; /* 4K */
-.byte4 0xFFF00000; /* 1M */
-.byte4 0xFFC00000; /* 4M */
-.page_prefix_table.end:
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