[Blackfin][PATCH] Add BF537 stamp board support
diff --git a/cpu/bf537/flush.S b/cpu/bf537/flush.S
new file mode 100644
index 0000000..c260a8f
--- /dev/null
+++ b/cpu/bf537/flush.S
@@ -0,0 +1,403 @@
+/* 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.
+ */
+#define ASSEMBLY
+
+#include <asm/linkage.h>
+#include <asm/cplb.h>
+#include <config.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 */
+
+ /* 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)
+ * 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*/
+ /* 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 = (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: