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Subject[PATCH 02/13] DMAENGINE: add generic PrimeCell interface to COH 901 318 v7
Date
This extends the DMA engine driver for the COH 901 318 used in the
U300 platform with the generic PrimeCell interface.

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
---
drivers/dma/coh901318.c | 154 +++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 154 insertions(+), 0 deletions(-)

diff --git a/drivers/dma/coh901318.c b/drivers/dma/coh901318.c
index a724e6b..6b21069 100644
--- a/drivers/dma/coh901318.c
+++ b/drivers/dma/coh901318.c
@@ -21,6 +21,7 @@
#include <linux/uaccess.h>
#include <linux/debugfs.h>
#include <mach/coh901318.h>
+#include <linux/amba/dma.h>

#include "coh901318_lli.h"

@@ -72,6 +73,9 @@ struct coh901318_chan {
unsigned long nbr_active_done;
unsigned long busy;

+ u32 amba_addr;
+ u32 amba_ctrl;
+
struct coh901318_base *base;
};

@@ -190,6 +194,9 @@ static inline struct coh901318_chan *to_coh901318_chan(struct dma_chan *chan)
static inline dma_addr_t
cohc_dev_addr(struct coh901318_chan *cohc)
{
+ /* PrimeCell supplied address will take precedence */
+ if (cohc->amba_addr)
+ return cohc->amba_addr;
return cohc->base->platform->chan_conf[cohc->id].dev_addr;
}

@@ -1055,6 +1062,14 @@ coh901318_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,

params = cohc_chan_param(cohc);
config = params->config;
+ /*
+ * Add primecell-specific control on top, make
+ * sure the bits you set per peripheral channel are
+ * cleared in the default config from the platform.
+ */
+ ctrl_chained |= cohc->amba_ctrl;
+ ctrl_last |= cohc->amba_ctrl;
+ ctrl |= cohc->amba_ctrl;

if (direction == DMA_TO_DEVICE) {
u32 tx_flags = COH901318_CX_CTRL_PRDD_SOURCE |
@@ -1113,6 +1128,12 @@ coh901318_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
if (ret)
goto err_lli_fill;

+ /*
+ * Set the default ctrl for the channel to the one from the lli,
+ * things may have changed due to odd buffer alignment etc.
+ */
+ coh901318_set_ctrl(cohc, lli->control);
+
COH_DBG(coh901318_list_print(cohc, lli));

/* Pick a descriptor to handle this transfer */
@@ -1175,6 +1196,130 @@ coh901318_issue_pending(struct dma_chan *chan)
spin_unlock_irqrestore(&cohc->lock, flags);
}

+/*
+ * Here we wrap in the PrimeCell dma interface
+ */
+struct burst_table {
+ int burst_8bit;
+ int burst_16bit;
+ int burst_32bit;
+ u32 reg;
+};
+
+static const struct burst_table burst_sizes[] = {
+ {
+ .burst_8bit = 64,
+ .burst_16bit = 32,
+ .burst_32bit = 16,
+ .reg = COH901318_CX_CTRL_BURST_COUNT_64_BYTES,
+ },
+ {
+ .burst_8bit = 48,
+ .burst_16bit = 24,
+ .burst_32bit = 12,
+ .reg = COH901318_CX_CTRL_BURST_COUNT_48_BYTES,
+ },
+ {
+ .burst_8bit = 32,
+ .burst_16bit = 16,
+ .burst_32bit = 8,
+ .reg = COH901318_CX_CTRL_BURST_COUNT_32_BYTES,
+ },
+ {
+ .burst_8bit = 16,
+ .burst_16bit = 8,
+ .burst_32bit = 4,
+ .reg = COH901318_CX_CTRL_BURST_COUNT_16_BYTES,
+ },
+ {
+ .burst_8bit = 8,
+ .burst_16bit = 4,
+ .burst_32bit = 2,
+ .reg = COH901318_CX_CTRL_BURST_COUNT_8_BYTES,
+ },
+ {
+ .burst_8bit = 4,
+ .burst_16bit = 2,
+ .burst_32bit = 1,
+ .reg = COH901318_CX_CTRL_BURST_COUNT_4_BYTES,
+ },
+ {
+ .burst_8bit = 2,
+ .burst_16bit = 1,
+ .burst_32bit = 0,
+ .reg = COH901318_CX_CTRL_BURST_COUNT_2_BYTES,
+ },
+ {
+ .burst_8bit = 1,
+ .burst_16bit = 0,
+ .burst_32bit = 0,
+ .reg = COH901318_CX_CTRL_BURST_COUNT_1_BYTE,
+ },
+};
+
+static void coh901318_dma_set_ambaconfig(struct dma_chan *chan,
+ struct amba_dma_channel_config *config)
+{
+ struct coh901318_chan *cohc = to_coh901318_chan(chan);
+ int maxburst = config->maxburst;
+ u32 amba_ctrl = 0;
+ int i = 0;
+
+ dev_dbg(COHC_2_DEV(cohc), "configure channel for %d byte transfers\n",
+ config->addr_width);
+ switch (config->addr_width) {
+ case 1:
+ amba_ctrl |=
+ COH901318_CX_CTRL_SRC_BUS_SIZE_8_BITS |
+ COH901318_CX_CTRL_DST_BUS_SIZE_8_BITS;
+
+ while (i < ARRAY_SIZE(burst_sizes)) {
+ if (burst_sizes[i].burst_8bit <= maxburst)
+ break;
+ i++;
+ }
+
+ break;
+ case 2:
+ amba_ctrl |=
+ COH901318_CX_CTRL_SRC_BUS_SIZE_16_BITS |
+ COH901318_CX_CTRL_DST_BUS_SIZE_16_BITS;
+
+ while (i < ARRAY_SIZE(burst_sizes)) {
+ if (burst_sizes[i].burst_16bit <= maxburst)
+ break;
+ i++;
+ }
+
+ break;
+ case 4:
+ /* Direction doesn't matter here, it's 32/32 bits */
+ amba_ctrl |=
+ COH901318_CX_CTRL_SRC_BUS_SIZE_32_BITS |
+ COH901318_CX_CTRL_DST_BUS_SIZE_32_BITS;
+
+ while (i < ARRAY_SIZE(burst_sizes)) {
+ if (burst_sizes[i].burst_32bit <= maxburst)
+ break;
+ i++;
+ }
+
+ break;
+ default:
+ dev_err(COHC_2_DEV(cohc),
+ "bad ambaconfig: alien address width\n");
+ return;
+ }
+
+ amba_ctrl |= burst_sizes[i].reg;
+ dev_dbg(COHC_2_DEV(cohc),
+ "selected burst size %d bytes for address width %d bytes, maxburst %d\n",
+ burst_sizes[i].burst_8bit, config->addr_width, maxburst);
+
+ cohc->amba_addr = config->addr;
+ cohc->amba_ctrl = amba_ctrl;
+}
+
static int
coh901318_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
unsigned long arg)
@@ -1184,6 +1329,14 @@ coh901318_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
struct coh901318_desc *cohd;
void __iomem *virtbase = cohc->base->virtbase;

+ if (cmd == DMA_CONFIG_AMBA) {
+ struct amba_dma_channel_config *config =
+ (struct amba_dma_channel_config *) arg;
+
+ coh901318_dma_set_ambaconfig(chan, config);
+ return 0;
+ }
+
if (cmd == DMA_PAUSE) {
coh901318_pause(chan);
return 0;
@@ -1240,6 +1393,7 @@ coh901318_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,

return 0;
}
+
void coh901318_base_init(struct dma_device *dma, const int *pick_chans,
struct coh901318_base *base)
{
--
1.6.3.3


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