summaryrefslogtreecommitdiffstats
path: root/drivers/dma/coh901318_lli.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/dma/coh901318_lli.c')
-rw-r--r--drivers/dma/coh901318_lli.c318
1 files changed, 318 insertions, 0 deletions
diff --git a/drivers/dma/coh901318_lli.c b/drivers/dma/coh901318_lli.c
new file mode 100644
index 000000000000..f5120f238a4d
--- /dev/null
+++ b/drivers/dma/coh901318_lli.c
@@ -0,0 +1,318 @@
+/*
+ * driver/dma/coh901318_lli.c
+ *
+ * Copyright (C) 2007-2009 ST-Ericsson
+ * License terms: GNU General Public License (GPL) version 2
+ * Support functions for handling lli for dma
+ * Author: Per Friden <per.friden@stericsson.com>
+ */
+
+#include <linux/dma-mapping.h>
+#include <linux/spinlock.h>
+#include <linux/dmapool.h>
+#include <linux/memory.h>
+#include <mach/coh901318.h>
+
+#include "coh901318_lli.h"
+
+#if (defined(CONFIG_DEBUG_FS) && defined(CONFIG_U300_DEBUG))
+#define DEBUGFS_POOL_COUNTER_RESET(pool) (pool->debugfs_pool_counter = 0)
+#define DEBUGFS_POOL_COUNTER_ADD(pool, add) (pool->debugfs_pool_counter += add)
+#else
+#define DEBUGFS_POOL_COUNTER_RESET(pool)
+#define DEBUGFS_POOL_COUNTER_ADD(pool, add)
+#endif
+
+static struct coh901318_lli *
+coh901318_lli_next(struct coh901318_lli *data)
+{
+ if (data == NULL || data->link_addr == 0)
+ return NULL;
+
+ return (struct coh901318_lli *) data->virt_link_addr;
+}
+
+int coh901318_pool_create(struct coh901318_pool *pool,
+ struct device *dev,
+ size_t size, size_t align)
+{
+ spin_lock_init(&pool->lock);
+ pool->dev = dev;
+ pool->dmapool = dma_pool_create("lli_pool", dev, size, align, 0);
+
+ DEBUGFS_POOL_COUNTER_RESET(pool);
+ return 0;
+}
+
+int coh901318_pool_destroy(struct coh901318_pool *pool)
+{
+
+ dma_pool_destroy(pool->dmapool);
+ return 0;
+}
+
+struct coh901318_lli *
+coh901318_lli_alloc(struct coh901318_pool *pool, unsigned int len)
+{
+ int i;
+ struct coh901318_lli *head;
+ struct coh901318_lli *lli;
+ struct coh901318_lli *lli_prev;
+ dma_addr_t phy;
+
+ if (len == 0)
+ goto err;
+
+ spin_lock(&pool->lock);
+
+ head = dma_pool_alloc(pool->dmapool, GFP_NOWAIT, &phy);
+
+ if (head == NULL)
+ goto err;
+
+ DEBUGFS_POOL_COUNTER_ADD(pool, 1);
+
+ lli = head;
+ lli->phy_this = phy;
+
+ for (i = 1; i < len; i++) {
+ lli_prev = lli;
+
+ lli = dma_pool_alloc(pool->dmapool, GFP_NOWAIT, &phy);
+
+ if (lli == NULL)
+ goto err_clean_up;
+
+ DEBUGFS_POOL_COUNTER_ADD(pool, 1);
+ lli->phy_this = phy;
+
+ lli_prev->link_addr = phy;
+ lli_prev->virt_link_addr = lli;
+ }
+
+ lli->link_addr = 0x00000000U;
+
+ spin_unlock(&pool->lock);
+
+ return head;
+
+ err:
+ spin_unlock(&pool->lock);
+ return NULL;
+
+ err_clean_up:
+ lli_prev->link_addr = 0x00000000U;
+ spin_unlock(&pool->lock);
+ coh901318_lli_free(pool, &head);
+ return NULL;
+}
+
+void coh901318_lli_free(struct coh901318_pool *pool,
+ struct coh901318_lli **lli)
+{
+ struct coh901318_lli *l;
+ struct coh901318_lli *next;
+
+ if (lli == NULL)
+ return;
+
+ l = *lli;
+
+ if (l == NULL)
+ return;
+
+ spin_lock(&pool->lock);
+
+ while (l->link_addr) {
+ next = l->virt_link_addr;
+ dma_pool_free(pool->dmapool, l, l->phy_this);
+ DEBUGFS_POOL_COUNTER_ADD(pool, -1);
+ l = next;
+ }
+ dma_pool_free(pool->dmapool, l, l->phy_this);
+ DEBUGFS_POOL_COUNTER_ADD(pool, -1);
+
+ spin_unlock(&pool->lock);
+ *lli = NULL;
+}
+
+int
+coh901318_lli_fill_memcpy(struct coh901318_pool *pool,
+ struct coh901318_lli *lli,
+ dma_addr_t source, unsigned int size,
+ dma_addr_t destination, u32 ctrl_chained,
+ u32 ctrl_eom)
+{
+ int s = size;
+ dma_addr_t src = source;
+ dma_addr_t dst = destination;
+
+ lli->src_addr = src;
+ lli->dst_addr = dst;
+
+ while (lli->link_addr) {
+ lli->control = ctrl_chained | MAX_DMA_PACKET_SIZE;
+ lli->src_addr = src;
+ lli->dst_addr = dst;
+
+ s -= MAX_DMA_PACKET_SIZE;
+ lli = coh901318_lli_next(lli);
+
+ src += MAX_DMA_PACKET_SIZE;
+ dst += MAX_DMA_PACKET_SIZE;
+ }
+
+ lli->control = ctrl_eom | s;
+ lli->src_addr = src;
+ lli->dst_addr = dst;
+
+ /* One irq per single transfer */
+ return 1;
+}
+
+int
+coh901318_lli_fill_single(struct coh901318_pool *pool,
+ struct coh901318_lli *lli,
+ dma_addr_t buf, unsigned int size,
+ dma_addr_t dev_addr, u32 ctrl_chained, u32 ctrl_eom,
+ enum dma_data_direction dir)
+{
+ int s = size;
+ dma_addr_t src;
+ dma_addr_t dst;
+
+
+ if (dir == DMA_TO_DEVICE) {
+ src = buf;
+ dst = dev_addr;
+
+ } else if (dir == DMA_FROM_DEVICE) {
+
+ src = dev_addr;
+ dst = buf;
+ } else {
+ return -EINVAL;
+ }
+
+ while (lli->link_addr) {
+ size_t block_size = MAX_DMA_PACKET_SIZE;
+ lli->control = ctrl_chained | MAX_DMA_PACKET_SIZE;
+
+ /* If we are on the next-to-final block and there will
+ * be less than half a DMA packet left for the last
+ * block, then we want to make this block a little
+ * smaller to balance the sizes. This is meant to
+ * avoid too small transfers if the buffer size is
+ * (MAX_DMA_PACKET_SIZE*N + 1) */
+ if (s < (MAX_DMA_PACKET_SIZE + MAX_DMA_PACKET_SIZE/2))
+ block_size = MAX_DMA_PACKET_SIZE/2;
+
+ s -= block_size;
+ lli->src_addr = src;
+ lli->dst_addr = dst;
+
+ lli = coh901318_lli_next(lli);
+
+ if (dir == DMA_TO_DEVICE)
+ src += block_size;
+ else if (dir == DMA_FROM_DEVICE)
+ dst += block_size;
+ }
+
+ lli->control = ctrl_eom | s;
+ lli->src_addr = src;
+ lli->dst_addr = dst;
+
+ /* One irq per single transfer */
+ return 1;
+}
+
+int
+coh901318_lli_fill_sg(struct coh901318_pool *pool,
+ struct coh901318_lli *lli,
+ struct scatterlist *sgl, unsigned int nents,
+ dma_addr_t dev_addr, u32 ctrl_chained, u32 ctrl,
+ u32 ctrl_last,
+ enum dma_data_direction dir, u32 ctrl_irq_mask)
+{
+ int i;
+ struct scatterlist *sg;
+ u32 ctrl_sg;
+ dma_addr_t src = 0;
+ dma_addr_t dst = 0;
+ int nbr_of_irq = 0;
+ u32 bytes_to_transfer;
+ u32 elem_size;
+
+ if (lli == NULL)
+ goto err;
+
+ spin_lock(&pool->lock);
+
+ if (dir == DMA_TO_DEVICE)
+ dst = dev_addr;
+ else if (dir == DMA_FROM_DEVICE)
+ src = dev_addr;
+ else
+ goto err;
+
+ for_each_sg(sgl, sg, nents, i) {
+ if (sg_is_chain(sg)) {
+ /* sg continues to the next sg-element don't
+ * send ctrl_finish until the last
+ * sg-element in the chain
+ */
+ ctrl_sg = ctrl_chained;
+ } else if (i == nents - 1)
+ ctrl_sg = ctrl_last;
+ else
+ ctrl_sg = ctrl ? ctrl : ctrl_last;
+
+
+ if ((ctrl_sg & ctrl_irq_mask))
+ nbr_of_irq++;
+
+ if (dir == DMA_TO_DEVICE)
+ /* increment source address */
+ src = sg_dma_address(sg);
+ else
+ /* increment destination address */
+ dst = sg_dma_address(sg);
+
+ bytes_to_transfer = sg_dma_len(sg);
+
+ while (bytes_to_transfer) {
+ u32 val;
+
+ if (bytes_to_transfer > MAX_DMA_PACKET_SIZE) {
+ elem_size = MAX_DMA_PACKET_SIZE;
+ val = ctrl_chained;
+ } else {
+ elem_size = bytes_to_transfer;
+ val = ctrl_sg;
+ }
+
+ lli->control = val | elem_size;
+ lli->src_addr = src;
+ lli->dst_addr = dst;
+
+ if (dir == DMA_FROM_DEVICE)
+ dst += elem_size;
+ else
+ src += elem_size;
+
+ BUG_ON(lli->link_addr & 3);
+
+ bytes_to_transfer -= elem_size;
+ lli = coh901318_lli_next(lli);
+ }
+
+ }
+ spin_unlock(&pool->lock);
+
+ /* There can be many IRQs per sg transfer */
+ return nbr_of_irq;
+ err:
+ spin_unlock(&pool->lock);
+ return -EINVAL;
+}
OpenPOWER on IntegriCloud