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-rw-r--r--arch/arm/mach-davinci/dma.c137
1 files changed, 137 insertions, 0 deletions
diff --git a/arch/arm/mach-davinci/dma.c b/arch/arm/mach-davinci/dma.c
index e6d7e6aca336..f2e57d272958 100644
--- a/arch/arm/mach-davinci/dma.c
+++ b/arch/arm/mach-davinci/dma.c
@@ -509,6 +509,45 @@ static irqreturn_t dma_tc1err_handler(int irq, void *data)
return IRQ_HANDLED;
}
+static int reserve_contiguous_params(int ctlr, unsigned int id,
+ unsigned int num_params,
+ unsigned int start_param)
+{
+ int i, j;
+ unsigned int count = num_params;
+
+ for (i = start_param; i < edma_info[ctlr]->num_slots; ++i) {
+ j = EDMA_CHAN_SLOT(i);
+ if (!test_and_set_bit(j, edma_info[ctlr]->edma_inuse))
+ count--;
+ if (count == 0)
+ break;
+ else if (id == EDMA_CONT_PARAMS_FIXED_EXACT)
+ break;
+ else
+ count = num_params;
+ }
+
+ /*
+ * We have to clear any bits that we set
+ * if we run out parameter RAMs, i.e we do find a set
+ * of contiguous parameter RAMs but do not find the exact number
+ * requested as we may reach the total number of parameter RAMs
+ */
+ if (count) {
+ for (j = i - num_params + count + 1; j <= i ; ++j)
+ clear_bit(j, edma_info[ctlr]->edma_inuse);
+
+ return -EBUSY;
+ }
+
+ for (j = i - num_params + 1; j <= i; ++j)
+ memcpy_toio(edmacc_regs_base[ctlr] + PARM_OFFSET(j),
+ &dummy_paramset, PARM_SIZE);
+
+ return EDMA_CTLR_CHAN(ctlr, i - num_params + 1);
+}
+
/*-----------------------------------------------------------------------*/
/* Resource alloc/free: dma channels, parameter RAM slots */
@@ -700,6 +739,104 @@ void edma_free_slot(unsigned slot)
}
EXPORT_SYMBOL(edma_free_slot);
+
+/**
+ * edma_alloc_cont_slots- alloc contiguous parameter RAM slots
+ * The API will return the starting point of a set of
+ * contiguous PARAM's that have been requested
+ *
+ * @id: can only be EDMA_CONT_PARAMS_ANY or EDMA_CONT_PARAMS_FIXED_EXACT
+ * or EDMA_CONT_PARAMS_FIXED_NOT_EXACT
+ * @count: number of contiguous Paramter RAM's
+ * @param - the start value of Parameter RAM that should be passed if id
+ * is EDMA_CONT_PARAMS_FIXED_EXACT or EDMA_CONT_PARAMS_FIXED_NOT_EXACT
+ *
+ * If id is EDMA_CONT_PARAMS_ANY then the API starts looking for a set of
+ * contiguous Parameter RAMs from parameter RAM 64 in the case of DaVinci SOCs
+ * and 32 in the case of Primus
+ *
+ * If id is EDMA_CONT_PARAMS_FIXED_EXACT then the API starts looking for a
+ * set of contiguous parameter RAMs from the "param" that is passed as an
+ * argument to the API.
+ *
+ * If id is EDMA_CONT_PARAMS_FIXED_NOT_EXACT then the API initially tries
+ * starts looking for a set of contiguous parameter RAMs from the "param"
+ * that is passed as an argument to the API. On failure the API will try to
+ * find a set of contiguous Parameter RAMs in the remaining Parameter RAMs
+ */
+int edma_alloc_cont_slots(unsigned ctlr, unsigned int id, int slot, int count)
+{
+ /*
+ * The start slot requested should be greater than
+ * the number of channels and lesser than the total number
+ * of slots
+ */
+ if (slot < edma_info[ctlr]->num_channels ||
+ slot >= edma_info[ctlr]->num_slots)
+ return -EINVAL;
+
+ /*
+ * The number of parameter RAMs requested cannot be less than 1
+ * and cannot be more than the number of slots minus the number of
+ * channels
+ */
+ if (count < 1 || count >
+ (edma_info[ctlr]->num_slots - edma_info[ctlr]->num_channels))
+ return -EINVAL;
+
+ switch (id) {
+ case EDMA_CONT_PARAMS_ANY:
+ return reserve_contiguous_params(ctlr, id, count,
+ edma_info[ctlr]->num_channels);
+ case EDMA_CONT_PARAMS_FIXED_EXACT:
+ case EDMA_CONT_PARAMS_FIXED_NOT_EXACT:
+ return reserve_contiguous_params(ctlr, id, count, slot);
+ default:
+ return -EINVAL;
+ }
+
+}
+EXPORT_SYMBOL(edma_alloc_cont_slots);
+
+/**
+ * edma_free_cont_slots - deallocate DMA parameter RAMs
+ * @slot: first parameter RAM of a set of parameter RAMs to be freed
+ * @count: the number of contiguous parameter RAMs to be freed
+ *
+ * This deallocates the parameter RAM slots allocated by
+ * edma_alloc_cont_slots.
+ * Callers/applications need to keep track of sets of contiguous
+ * parameter RAMs that have been allocated using the edma_alloc_cont_slots
+ * API.
+ * Callers are responsible for ensuring the slots are inactive, and will
+ * not be activated.
+ */
+int edma_free_cont_slots(unsigned slot, int count)
+{
+ unsigned ctlr;
+ int i;
+
+ ctlr = EDMA_CTLR(slot);
+ slot = EDMA_CHAN_SLOT(slot);
+
+ if (slot < edma_info[ctlr]->num_channels ||
+ slot >= edma_info[ctlr]->num_slots ||
+ count < 1)
+ return -EINVAL;
+
+ for (i = slot; i < slot + count; ++i) {
+ ctlr = EDMA_CTLR(i);
+ slot = EDMA_CHAN_SLOT(i);
+
+ memcpy_toio(edmacc_regs_base[ctlr] + PARM_OFFSET(slot),
+ &dummy_paramset, PARM_SIZE);
+ clear_bit(slot, edma_info[ctlr]->edma_inuse);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(edma_free_cont_slots);
+
/*-----------------------------------------------------------------------*/
/* Parameter RAM operations (i) -- read/write partial slots */