[PATCH 1/4] dmaengine: pl08x: support dt channel assignment
Joachim Eastwood
manabian at gmail.com
Sat Jul 11 05:12:04 PDT 2015
From: Linus Walleij <linus.walleij at linaro.org>
Add support for assigning DMA channels from a device tree.
[je: remove channel sub-node parsing, dynamic channel creation on xlate]
Signed-off-by: Linus Walleij <linus.walleij at linaro.org>
Signed-off-by: Joachim Eastwood <manabian at gmail.com>
---
drivers/dma/amba-pl08x.c | 192 ++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 189 insertions(+), 3 deletions(-)
diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c
index 5de3cf453f35..9b42c0588550 100644
--- a/drivers/dma/amba-pl08x.c
+++ b/drivers/dma/amba-pl08x.c
@@ -83,6 +83,8 @@
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_dma.h>
#include <linux/pm_runtime.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
@@ -2030,10 +2032,188 @@ static inline void init_pl08x_debugfs(struct pl08x_driver_data *pl08x)
}
#endif
+#ifdef CONFIG_OF
+static struct dma_chan *pl08x_find_chan_id(struct pl08x_driver_data *pl08x,
+ u32 id)
+{
+ struct pl08x_dma_chan *chan;
+
+ list_for_each_entry(chan, &pl08x->slave.channels, vc.chan.device_node) {
+ if (chan->signal == id)
+ return &chan->vc.chan;
+ }
+
+ return NULL;
+}
+
+static struct dma_chan *pl08x_of_xlate(struct of_phandle_args *dma_spec,
+ struct of_dma *ofdma)
+{
+ struct pl08x_driver_data *pl08x = ofdma->of_dma_data;
+ struct pl08x_channel_data *data;
+ struct pl08x_dma_chan *chan;
+ struct dma_chan *dma_chan;
+
+ if (!pl08x)
+ return NULL;
+
+ if (dma_spec->args_count != 2)
+ return NULL;
+
+ dma_chan = pl08x_find_chan_id(pl08x, dma_spec->args[0]);
+ if (dma_chan)
+ return dma_get_slave_channel(dma_chan);
+
+ chan = devm_kzalloc(pl08x->slave.dev, sizeof(*chan) + sizeof(*data),
+ GFP_KERNEL);
+ if (!chan)
+ return NULL;
+
+ data = (void *)&chan[1];
+ data->bus_id = "(none)";
+ data->periph_buses = dma_spec->args[1];
+
+ chan->cd = data;
+ chan->host = pl08x;
+ chan->slave = true;
+ chan->name = data->bus_id;
+ chan->state = PL08X_CHAN_IDLE;
+ chan->signal = dma_spec->args[0];
+ chan->vc.desc_free = pl08x_desc_free;
+
+ vchan_init(&chan->vc, &pl08x->slave);
+
+ return dma_get_slave_channel(&chan->vc.chan);
+}
+
+static int pl08x_of_probe(struct amba_device *adev,
+ struct pl08x_driver_data *pl08x,
+ struct device_node *np)
+{
+ struct pl08x_platform_data *pd;
+ u32 cctl_memcpy = 0;
+ u32 val;
+ int ret;
+
+ pd = devm_kzalloc(&adev->dev, sizeof(*pd), GFP_KERNEL);
+ if (!pd)
+ return -ENOMEM;
+
+ /* Eligible bus masters for fetching LLIs */
+ if (of_property_read_bool(np, "lli-bus-interface-ahb1"))
+ pd->lli_buses |= PL08X_AHB1;
+ if (of_property_read_bool(np, "lli-bus-interface-ahb2"))
+ pd->lli_buses |= PL08X_AHB2;
+ if (!pd->lli_buses) {
+ dev_info(&adev->dev, "no bus masters for LLIs stated, assume all\n");
+ pd->lli_buses |= PL08X_AHB1 | PL08X_AHB2;
+ }
+
+ /* Eligible bus masters for memory access */
+ if (of_property_read_bool(np, "mem-bus-interface-ahb1"))
+ pd->mem_buses |= PL08X_AHB1;
+ if (of_property_read_bool(np, "mem-bus-interface-ahb2"))
+ pd->mem_buses |= PL08X_AHB2;
+ if (!pd->mem_buses) {
+ dev_info(&adev->dev, "no bus masters for memory stated, assume all\n");
+ pd->mem_buses |= PL08X_AHB1 | PL08X_AHB2;
+ }
+
+ /* Parse the memcpy channel properties */
+ ret = of_property_read_u32(np, "memcpy-burst-size", &val);
+ if (ret) {
+ dev_info(&adev->dev, "no memcpy burst size specified, using 1 byte\n");
+ val = 1;
+ }
+ switch (val) {
+ default:
+ dev_err(&adev->dev, "illegal burst size for memcpy, set to 1\n");
+ /* Fall through */
+ case 1:
+ cctl_memcpy |= PL080_BSIZE_1 << PL080_CONTROL_SB_SIZE_SHIFT |
+ PL080_BSIZE_1 << PL080_CONTROL_DB_SIZE_SHIFT;
+ break;
+ case 4:
+ cctl_memcpy |= PL080_BSIZE_4 << PL080_CONTROL_SB_SIZE_SHIFT |
+ PL080_BSIZE_4 << PL080_CONTROL_DB_SIZE_SHIFT;
+ break;
+ case 8:
+ cctl_memcpy |= PL080_BSIZE_8 << PL080_CONTROL_SB_SIZE_SHIFT |
+ PL080_BSIZE_8 << PL080_CONTROL_DB_SIZE_SHIFT;
+ break;
+ case 16:
+ cctl_memcpy |= PL080_BSIZE_16 << PL080_CONTROL_SB_SIZE_SHIFT |
+ PL080_BSIZE_16 << PL080_CONTROL_DB_SIZE_SHIFT;
+ break;
+ case 32:
+ cctl_memcpy |= PL080_BSIZE_32 << PL080_CONTROL_SB_SIZE_SHIFT |
+ PL080_BSIZE_32 << PL080_CONTROL_DB_SIZE_SHIFT;
+ break;
+ case 64:
+ cctl_memcpy |= PL080_BSIZE_64 << PL080_CONTROL_SB_SIZE_SHIFT |
+ PL080_BSIZE_64 << PL080_CONTROL_DB_SIZE_SHIFT;
+ break;
+ case 128:
+ cctl_memcpy |= PL080_BSIZE_128 << PL080_CONTROL_SB_SIZE_SHIFT |
+ PL080_BSIZE_128 << PL080_CONTROL_DB_SIZE_SHIFT;
+ break;
+ case 256:
+ cctl_memcpy |= PL080_BSIZE_256 << PL080_CONTROL_SB_SIZE_SHIFT |
+ PL080_BSIZE_256 << PL080_CONTROL_DB_SIZE_SHIFT;
+ break;
+ }
+
+ ret = of_property_read_u32(np, "memcpy-bus-width", &val);
+ if (ret) {
+ dev_info(&adev->dev, "no memcpy bus width specified, using 8 bits\n");
+ val = 8;
+ }
+ switch (val) {
+ default:
+ dev_err(&adev->dev, "illegal bus width for memcpy, set to 8 bits\n");
+ /* Fall through */
+ case 8:
+ cctl_memcpy |= PL080_WIDTH_8BIT << PL080_CONTROL_SWIDTH_SHIFT |
+ PL080_WIDTH_8BIT << PL080_CONTROL_DWIDTH_SHIFT;
+ break;
+ case 16:
+ cctl_memcpy |= PL080_WIDTH_16BIT << PL080_CONTROL_SWIDTH_SHIFT |
+ PL080_WIDTH_16BIT << PL080_CONTROL_DWIDTH_SHIFT;
+ break;
+ case 32:
+ cctl_memcpy |= PL080_WIDTH_32BIT << PL080_CONTROL_SWIDTH_SHIFT |
+ PL080_WIDTH_32BIT << PL080_CONTROL_DWIDTH_SHIFT;
+ break;
+ }
+
+ /* This is currently the only thing making sense */
+ cctl_memcpy |= PL080_CONTROL_PROT_SYS;
+
+ /* Set up memcpy channel */
+ pd->memcpy_channel.bus_id = "memcpy";
+ pd->memcpy_channel.cctl_memcpy = cctl_memcpy;
+ /* Use the buses that can access memory, obviously */
+ pd->memcpy_channel.periph_buses = pd->mem_buses;
+
+ pl08x->pd = pd;
+
+ return of_dma_controller_register(adev->dev.of_node, pl08x_of_xlate,
+ pl08x);
+}
+#else
+static inline int pl08x_of_probe(struct amba_device *adev,
+ struct pl08x_driver_data *pl08x,
+ struct device_node *np)
+{
+ return -EINVAL;
+}
+#endif
+
static int pl08x_probe(struct amba_device *adev, const struct amba_id *id)
{
struct pl08x_driver_data *pl08x;
const struct vendor_data *vd = id->data;
+ struct device_node *np = adev->dev.of_node;
u32 tsfr_size;
int ret = 0;
int i;
@@ -2093,9 +2273,15 @@ static int pl08x_probe(struct amba_device *adev, const struct amba_id *id)
/* Get the platform data */
pl08x->pd = dev_get_platdata(&adev->dev);
if (!pl08x->pd) {
- dev_err(&adev->dev, "no platform data supplied\n");
- ret = -EINVAL;
- goto out_no_platdata;
+ if (np) {
+ ret = pl08x_of_probe(adev, pl08x, np);
+ if (ret)
+ goto out_no_platdata;
+ } else {
+ dev_err(&adev->dev, "no platform data supplied\n");
+ ret = -EINVAL;
+ goto out_no_platdata;
+ }
}
/* Assign useful pointers to the driver state */
--
1.8.0
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