[PATCH 5/9] dmaengine: pl330: provide ACPI dmaengine interface

From: Wang Hongcheng
Date: Thu Dec 03 2015 - 22:40:35 EST


register acpi_dma controller, so ACPI devices can request pl330 DMA
channel.
A filter is added in private data for Carrizo specific hardware
design

Signed-off-by: Wang Hongcheng <annie.wang@xxxxxxx>
---
drivers/acpi/acpi_apd.c | 12 ++++++++++++
drivers/dma/pl330.c | 38 ++++++++++++++++++++++++++++++++++++++
include/linux/amba/pl330.h | 1 +
3 files changed, 51 insertions(+)

diff --git a/drivers/acpi/acpi_apd.c b/drivers/acpi/acpi_apd.c
index 7a582f5..906a20f 100644
--- a/drivers/acpi/acpi_apd.c
+++ b/drivers/acpi/acpi_apd.c
@@ -38,12 +38,15 @@ struct apd_private_data;

static u8 peri_id[2] = { 0, 1 };

+static int apd_acpi_xlate_filter(int slave_id, struct device *dev);
+
static struct dma_pl330_platdata amd_pl330 = {
.nr_valid_peri = 2,
.peri_id = peri_id,
.has_no_cap_mask = true,
.mcbuf_sz = 0,
.flags = IRQF_SHARED,
+ .acpi_xlate_filter = apd_acpi_xlate_filter,
};

/**
@@ -68,6 +71,15 @@ struct apd_private_data {
const struct apd_device_desc *dev_desc;
};

+int apd_acpi_xlate_filter(int slave_id, struct device *dev)
+{
+ if (((slave_id == 1) && (!strcmp(dev_name(dev), "AMD0020:00DMA")))
+ || ((slave_id == 2) && (!strcmp(dev_name(dev), "AMD0020:01DMA"))))
+ return 0;
+
+ return 1;
+}
+
#ifdef CONFIG_X86_AMD_PLATFORM_DEVICE
#define APD_ADDR(desc) ((unsigned long)&desc)

diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index 8300969..9d7af0d 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -2079,6 +2079,35 @@ static struct dma_chan *of_dma_pl330_xlate(struct of_phandle_args *dma_spec,
return dma_get_slave_channel(&pl330->peripherals[chan_id].chan);
}

+static struct dma_chan *acpi_dma_pl330_xlate(struct acpi_dma_spec *dma_spec,
+ struct acpi_dma *adma)
+{
+ struct pl330_dmac *pl330 = adma->data;
+ struct dma_pl330_platdata *pdat;
+ unsigned int chan_id;
+ int ret;
+
+ if (!dma_spec)
+ return NULL;
+
+ if (!adma)
+ return NULL;
+
+ pdat = dev_get_platdata(adma->dev);
+
+ chan_id = dma_spec->chan_id;
+ if (chan_id >= pl330->num_peripherals)
+ return NULL;
+
+ if (pdat->acpi_xlate_filter) {
+ ret = pdat->acpi_xlate_filter(dma_spec->slave_id, adma->dev);
+ if (ret)
+ return NULL;
+ }
+
+ return dma_get_slave_channel(&pl330->peripherals[chan_id].chan);
+}
+
static int pl330_alloc_chan_resources(struct dma_chan *chan)
{
struct dma_pl330_chan *pch = to_pchan(chan);
@@ -2918,6 +2947,15 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id)
}
}

+ if (ACPI_HANDLE(&adev->dev)) {
+ ret = acpi_dma_controller_register(&adev->dev,
+ acpi_dma_pl330_xlate, pl330);
+ if (ret) {
+ dev_err(&adev->dev,
+ "unable to register DMA to the generic ACPI DMA helpers\n");
+ }
+ }
+
adev->dev.dma_parms = &pl330->dma_parms;

/*
diff --git a/include/linux/amba/pl330.h b/include/linux/amba/pl330.h
index 605d00f..85bebbb 100644
--- a/include/linux/amba/pl330.h
+++ b/include/linux/amba/pl330.h
@@ -32,6 +32,7 @@ struct dma_pl330_platdata {
unsigned mcbuf_sz;
/*flags for irq sharing, default is non-shared*/
unsigned flags;
+ int (*acpi_xlate_filter)(int slave_id, struct device *dev);
};

extern bool pl330_filter(struct dma_chan *chan, void *param);
--
1.9.1

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