summaryrefslogtreecommitdiffstats
path: root/drivers/dma/bestcomm/sram.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/dma/bestcomm/sram.c')
-rw-r--r--drivers/dma/bestcomm/sram.c178
1 files changed, 178 insertions, 0 deletions
diff --git a/drivers/dma/bestcomm/sram.c b/drivers/dma/bestcomm/sram.c
new file mode 100644
index 00000000000..5e2ed30ba2c
--- /dev/null
+++ b/drivers/dma/bestcomm/sram.c
@@ -0,0 +1,178 @@
+/*
+ * Simple memory allocator for on-board SRAM
+ *
+ *
+ * Maintainer : Sylvain Munaut <tnt@246tNt.com>
+ *
+ * Copyright (C) 2005 Sylvain Munaut <tnt@246tNt.com>
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+#include <linux/ioport.h>
+#include <linux/of.h>
+
+#include <asm/io.h>
+#include <asm/mmu.h>
+
+#include <linux/fsl/bestcomm/sram.h>
+
+
+/* Struct keeping our 'state' */
+struct bcom_sram *bcom_sram = NULL;
+EXPORT_SYMBOL_GPL(bcom_sram); /* needed for inline functions */
+
+
+/* ======================================================================== */
+/* Public API */
+/* ======================================================================== */
+/* DO NOT USE in interrupts, if needed in irq handler, we should use the
+ _irqsave version of the spin_locks */
+
+int bcom_sram_init(struct device_node *sram_node, char *owner)
+{
+ int rv;
+ const u32 *regaddr_p;
+ u64 regaddr64, size64;
+ unsigned int psize;
+
+ /* Create our state struct */
+ if (bcom_sram) {
+ printk(KERN_ERR "%s: bcom_sram_init: "
+ "Already initialized !\n", owner);
+ return -EBUSY;
+ }
+
+ bcom_sram = kmalloc(sizeof(struct bcom_sram), GFP_KERNEL);
+ if (!bcom_sram) {
+ printk(KERN_ERR "%s: bcom_sram_init: "
+ "Couldn't allocate internal state !\n", owner);
+ return -ENOMEM;
+ }
+
+ /* Get address and size of the sram */
+ regaddr_p = of_get_address(sram_node, 0, &size64, NULL);
+ if (!regaddr_p) {
+ printk(KERN_ERR "%s: bcom_sram_init: "
+ "Invalid device node !\n", owner);
+ rv = -EINVAL;
+ goto error_free;
+ }
+
+ regaddr64 = of_translate_address(sram_node, regaddr_p);
+
+ bcom_sram->base_phys = (phys_addr_t) regaddr64;
+ bcom_sram->size = (unsigned int) size64;
+
+ /* Request region */
+ if (!request_mem_region(bcom_sram->base_phys, bcom_sram->size, owner)) {
+ printk(KERN_ERR "%s: bcom_sram_init: "
+ "Couldn't request region !\n", owner);
+ rv = -EBUSY;
+ goto error_free;
+ }
+
+ /* Map SRAM */
+ /* sram is not really __iomem */
+ bcom_sram->base_virt = (void*) ioremap(bcom_sram->base_phys, bcom_sram->size);
+
+ if (!bcom_sram->base_virt) {
+ printk(KERN_ERR "%s: bcom_sram_init: "
+ "Map error SRAM zone 0x%08lx (0x%0x)!\n",
+ owner, (long)bcom_sram->base_phys, bcom_sram->size );
+ rv = -ENOMEM;
+ goto error_release;
+ }
+
+ /* Create an rheap (defaults to 32 bits word alignment) */
+ bcom_sram->rh = rh_create(4);
+
+ /* Attach the free zones */
+#if 0
+ /* Currently disabled ... for future use only */
+ reg_addr_p = of_get_property(sram_node, "available", &psize);
+#else
+ regaddr_p = NULL;
+ psize = 0;
+#endif
+
+ if (!regaddr_p || !psize) {
+ /* Attach the whole zone */
+ rh_attach_region(bcom_sram->rh, 0, bcom_sram->size);
+ } else {
+ /* Attach each zone independently */
+ while (psize >= 2 * sizeof(u32)) {
+ phys_addr_t zbase = of_translate_address(sram_node, regaddr_p);
+ rh_attach_region(bcom_sram->rh, zbase - bcom_sram->base_phys, regaddr_p[1]);
+ regaddr_p += 2;
+ psize -= 2 * sizeof(u32);
+ }
+ }
+
+ /* Init our spinlock */
+ spin_lock_init(&bcom_sram->lock);
+
+ return 0;
+
+error_release:
+ release_mem_region(bcom_sram->base_phys, bcom_sram->size);
+error_free:
+ kfree(bcom_sram);
+ bcom_sram = NULL;
+
+ return rv;
+}
+EXPORT_SYMBOL_GPL(bcom_sram_init);
+
+void bcom_sram_cleanup(void)
+{
+ /* Free resources */
+ if (bcom_sram) {
+ rh_destroy(bcom_sram->rh);
+ iounmap((void __iomem *)bcom_sram->base_virt);
+ release_mem_region(bcom_sram->base_phys, bcom_sram->size);
+ kfree(bcom_sram);
+ bcom_sram = NULL;
+ }
+}
+EXPORT_SYMBOL_GPL(bcom_sram_cleanup);
+
+void* bcom_sram_alloc(int size, int align, phys_addr_t *phys)
+{
+ unsigned long offset;
+
+ spin_lock(&bcom_sram->lock);
+ offset = rh_alloc_align(bcom_sram->rh, size, align, NULL);
+ spin_unlock(&bcom_sram->lock);
+
+ if (IS_ERR_VALUE(offset))
+ return NULL;
+
+ *phys = bcom_sram->base_phys + offset;
+ return bcom_sram->base_virt + offset;
+}
+EXPORT_SYMBOL_GPL(bcom_sram_alloc);
+
+void bcom_sram_free(void *ptr)
+{
+ unsigned long offset;
+
+ if (!ptr)
+ return;
+
+ offset = ptr - bcom_sram->base_virt;
+
+ spin_lock(&bcom_sram->lock);
+ rh_free(bcom_sram->rh, offset);
+ spin_unlock(&bcom_sram->lock);
+}
+EXPORT_SYMBOL_GPL(bcom_sram_free);
+