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-rw-r--r--qemu/roms/SLOF/slof/allocator.c219
1 files changed, 219 insertions, 0 deletions
diff --git a/qemu/roms/SLOF/slof/allocator.c b/qemu/roms/SLOF/slof/allocator.c
new file mode 100644
index 000000000..279b50b9c
--- /dev/null
+++ b/qemu/roms/SLOF/slof/allocator.c
@@ -0,0 +1,219 @@
+/******************************************************************************
+ * Copyright (c) 2013 IBM Corporation
+ * All rights reserved.
+ * This program and the accompanying materials
+ * are made available under the terms of the BSD License
+ * which accompanies this distribution, and is available at
+ * http://www.opensource.org/licenses/bsd-license.php
+ *
+ * Contributors:
+ * IBM Corporation - initial implementation
+ *****************************************************************************/
+/*
+ * All functions concerning interface to slof
+ */
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <helpers.h>
+
+#undef DEBUG
+//#define DEBUG
+#ifdef DEBUG
+#define dprintf(_x ...) do { printf ("%s: ", __func__); printf(_x); } while (0);
+#else
+#define dprintf(_x ...)
+#endif
+
+#define DEFAULT_BLOCK_SIZE 4096
+
+#define BM_WORD_SIZE (sizeof(unsigned long))
+#define BM_WORD_BITS (BM_WORD_SIZE * 8)
+
+struct bitmap {
+ unsigned long start;
+ unsigned long size;
+ unsigned long bm_size;
+ unsigned long block_size;
+ unsigned long free_blocks;
+ unsigned long bmw[];
+};
+
+#define BIT(x) (1UL << x)
+#define BM_WORD(bmw, n) (bmw[n/BM_WORD_BITS])
+#define BM_WORD_MODULO(n) (n % BM_WORD_BITS)
+#define BM_NUM_BITS(reqsize, bsize) ((reqsize / bsize) + (reqsize % bsize? 1 : 0))
+
+void bm_clear_bit(unsigned long *bmw, int n)
+{
+ BM_WORD(bmw, n) &= ~BIT(BM_WORD_MODULO(n));
+}
+
+void bm_set_bit(unsigned long *bmw, int n)
+{
+ BM_WORD(bmw, n) |= BIT(BM_WORD_MODULO(n));
+}
+
+bool bm_test_bit(unsigned long *bmw, int n)
+{
+#ifdef DEBUG
+ //printf("BMW %x, bitpos %d, value %d\n", &BM_WORD(bmw, n), n, !!(BM_WORD(bmw, n) & BIT(BM_WORD_MODULO(n))));
+#endif
+ return !!(BM_WORD(bmw, n) & BIT(BM_WORD_MODULO(n)));
+}
+
+/* Improvement: can use FFS routines to get faster results */
+int bm_find_bits(struct bitmap *bm, unsigned int n_bits)
+{
+ unsigned int i, j, total_bits;
+ int found = -1;
+ dprintf("Finding %d bits set\n", n_bits);
+ total_bits = BM_NUM_BITS(bm->size, bm->block_size);
+ for(i = 0; i < total_bits; i++) {
+ if (!bm_test_bit(bm->bmw, i))
+ continue;
+ /* we have hit the boundary now, give up */
+ if (i + n_bits > total_bits)
+ break;
+ /* Lets find if we have consecutive bits set */
+ for(j = i; j < (i + n_bits); j++) {
+ if (!bm_test_bit(bm->bmw, (j)))
+ break;
+ }
+ /* Got it */
+ if (j == (i + n_bits)) {
+ found = i;
+ break;
+ }
+ }
+ return found;
+}
+
+void SLOF_bm_print(unsigned long handle)
+{
+ struct bitmap *bm;
+ unsigned int i;
+
+ if (!handle)
+ return;
+
+ bm = (struct bitmap *) handle;
+ printf("BITMAP: start %lx, size %ld, blocksize %ld\n\n",
+ bm->start, bm->size, bm->block_size);
+ printf("0 16 32 48 63\n");
+ for(i = 0; i < BM_NUM_BITS(bm->size, bm->block_size); i++) {
+ if (i > 0 && (i % 64 == 0))
+ printf("\n");
+ else if (i > 0 && (i % 8 == 0))
+ printf(" ");
+ printf("%d", bm_test_bit(bm->bmw, i));
+ }
+ printf("\n\n");
+}
+
+unsigned long SLOF_bm_allocator_init(unsigned long start, unsigned long size,
+ unsigned long blocksize)
+{
+ struct bitmap *bm;
+ unsigned long alloc_size, bm_size, n_bits;
+
+ dprintf("enter start %x, size %d, block-size %d\n", start, size, blocksize);
+
+ if (!size)
+ return 0;
+ if (!blocksize)
+ blocksize = DEFAULT_BLOCK_SIZE;
+
+ n_bits = BM_NUM_BITS(size, blocksize);
+ bm_size = (n_bits / BM_WORD_BITS) + ((n_bits % BM_WORD_BITS)? 1 : 0);
+ alloc_size = sizeof(struct bitmap) + bm_size * BM_WORD_SIZE;
+ dprintf("Size %ld, blocksize %ld, bm_size %ld, alloc_size %ld\n",
+ size, blocksize, bm_size, alloc_size);
+ bm = (struct bitmap *) SLOF_alloc_mem(alloc_size);
+ if (!bm)
+ return 0;
+ bm->start = start;
+ bm->size = size;
+ bm->bm_size = bm_size;
+ bm->block_size = blocksize;
+ bm->free_blocks = n_bits;
+ memset(bm->bmw, 0xFF, bm_size*BM_WORD_SIZE);
+ return (unsigned long)bm;
+}
+
+unsigned long SLOF_bm_alloc(unsigned long handle, unsigned long size)
+{
+ struct bitmap *bm;
+ unsigned long n_bits;
+ unsigned long addr;
+ unsigned int i;
+ int bitpos;
+
+ if (!handle)
+ return -1;
+
+ bm = (struct bitmap *) handle;
+
+ n_bits = BM_NUM_BITS(size, bm->block_size);
+ if (n_bits > bm->free_blocks)
+ return -1;
+
+ bitpos = bm_find_bits(bm, n_bits);
+ if (bitpos == -1)
+ return -1;
+
+ dprintf("BMW %d, bitpos %d\n", i, bitpos);
+ dprintf("size %d, block_size %d, n_bits %d\n", size, bm->block_size, n_bits);
+ for(i = bitpos; i < (bitpos + n_bits); i++) {
+#ifdef DEBUG
+ if (!bm_test_bit(bm->bmw, i))
+ dprintf("Warning: Bit already in use: %d\n", i);
+#endif
+ bm_clear_bit(bm->bmw, i);
+ }
+ bm->free_blocks -= n_bits;
+ addr = bm->start + bitpos * bm->block_size;
+ dprintf("BMW %d, bitpos %d addr %lx free_blocks %d\n", i, bitpos, addr, bm->free_blocks);
+ return addr;
+}
+
+void SLOF_bm_free(unsigned long handle, unsigned long ptr, unsigned long size)
+{
+ struct bitmap *bm;
+ unsigned long bitpos, n_bits;
+ unsigned long addr;
+ unsigned int i;
+
+ if (!handle)
+ return;
+
+ bm = (struct bitmap *) handle;
+ addr = (unsigned long ) ptr;
+ n_bits = BM_NUM_BITS(size, bm->block_size);
+ if (addr < bm->start || (bm->start + bm->size) < (addr + size)) {
+ printf("Error: Bitmap start %lx, size %ld, requested address %lx, size %ld\n",
+ bm->start, bm->size, addr, size);
+ return;
+ }
+ bitpos = (addr - bm->start) / bm->block_size;
+ bm->free_blocks += n_bits;
+
+#ifdef DEBUG
+ dprintf("addr %lx, bitpos %d\n", addr, bitpos);
+ dprintf("size %d, block_size %d, n_bits %d, free_blocks %d\n", size, bm->block_size, n_bits, bm->free_blocks);
+ if (addr % bm->block_size) {
+ dprintf("Warning: Address not aligned addr %lx\n", addr);
+ }
+#endif
+
+ for(i = bitpos; i < (bitpos + n_bits); i++) {
+#ifdef DEBUG
+ if (bm_test_bit(bm->bmw, i))
+ dprintf("Warning: Bit already set: %d\n", i);
+#endif
+ bm_set_bit(bm->bmw, i);
+ }
+
+ return;
+}