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Add device tree support for PL330 dma controller driver

PATCH Superseded Thomas Abraham 3 participants 12 messages Sep 1, 2011 – Sep 19, 2011

Subsystems (5)

v2 of 6 Superseded Latest is v6 →

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#0 lore raw

v2 cover Add device tree support for PL330 dma controller driver

This patchset adds device tree support for PL330 driver and uses it to add device tree support for Samsung platforms, specifically Exynos4.

First patch moves the pl330_filter function from Samsung specific wrappers to pl330 dma driver and also adds a check to ensure that the filter function proceeds only if it the dma channel being investigated belongs to pl330 dma controller instance.

Second patch adds support to infer the direction of the dma transfer using the direction specified with the transfer request instead of including this information in the platform data. This simlifies the addition of device tree support. Third patch simplifies the platform data for Exynos4 pl330 dma controllers. Similar patches simplifying the platform data for other Samsung platforms is under development.

Fourth patch adds device tree support for pl330 dma controller driver. A dma channel is represented using a phandle of the dma controller node and the channel id within that controller. Client driver request a dma channel using the phandle and channel id pair. Correspondingly, the pl330 filter function has been modified to lookup a channel based on this value.

Fifth patch adds device tree support for Samsung's DMA engine wrappers. Client drivers retrive the channel property from their device node and pass it to the wrappers. The wrapper functions use the property value as the filter function parameter. Sixth patch restricts the usage of pl330 device and platform data instances to non-dt platforms.

This patchset is based on Linux 3.1-rc3 with the following patch sets.

* To use DMA generic APIs for Samsung DMA - v7 - (15 patches)
* ARM: Samsung: use dma-pl330 device name for clock (3 patches)
* ARM: S5P64X0: Add the devname for DMA clock.
* ARM: SAMSUNG: register the second instance of PL330 DMAC (3 patches)

Changes since v1:
- Removed "arm,pl330-pdma" and "arm,pl330-mdma" compatible values.
- Removed "arm,primecell-periphid" and "arm,pl330-peri-reqs" property requirements.

Thomas Abraham (6):
DMA: PL330: move filter function into driver
DMA: PL330: Infer transfer direction from transfer request instead of platform data
ARM: EXYNOS4: Modify platform data for pl330 driver
DMA: PL330: Add device tree support
ARM: SAMSUNG: Add device tree support for pl330 dma engine wrappers
ARM: EXYNOS4: Limit usage of pl330 device instance to non-dt build

 .../devicetree/bindings/dma/arm-pl330.txt          |   29 +++
 arch/arm/mach-exynos4/Kconfig                      |    7 +
 arch/arm/mach-exynos4/Makefile                     |    3 +-
 arch/arm/mach-exynos4/dma.c                        |  223 ++++++--------------
 arch/arm/plat-samsung/dma-ops.c                    |   15 +-
 arch/arm/plat-samsung/include/plat/dma-ops.h       |    1 +
 arch/arm/plat-samsung/include/plat/dma-pl330.h     |    3 +-
 drivers/dma/pl330.c                                |  101 +++++----
 include/linux/amba/pl330.h                         |   15 +-
 9 files changed, 170 insertions(+), 227 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/dma/arm-pl330.txt
#1 lore raw

PATCH v2 1/6 DMA: PL330: move filter function into driver

The dma channel selection filter function is moved from plat-samsung into the pl330 driver. In additon to that, a check is added in the filter function to ensure that the channel on which the filter has been invoked is pl330 channel instance (and avoid any incorrect access of chan->private in a system with multiple types of DMA drivers).

---
 arch/arm/plat-samsung/dma-ops.c |    6 ------
 drivers/dma/pl330.c             |   15 +++++++++++++++
 include/linux/amba/pl330.h      |    2 ++
 3 files changed, 17 insertions(+), 6 deletions(-)
arch/arm/plat-samsung/dma-ops.c +0 -6
index 6e3d9ab..8d18425 100644
@@ -17,12 +17,6 @@
 
 #include <mach/dma.h>
 
-static inline bool pl330_filter(struct dma_chan *chan, void *param)
-{
-	struct dma_pl330_peri *peri = chan->private;
-	return peri->peri_id == (unsigned)param;
-}
-
 static unsigned samsung_dmadev_request(enum dma_ch dma_ch,
 				struct samsung_dma_info *info)
 {
drivers/dma/pl330.c +15 -0
index 95976cf..7df2516 100644
@@ -116,6 +116,9 @@ struct dma_pl330_desc {
 	struct dma_pl330_chan *pchan;
 };
 
+/* forward declaration */
+static struct amba_driver pl330_driver;
+
 static inline struct dma_pl330_chan *
 to_pchan(struct dma_chan *ch)
 {
@@ -267,6 +270,18 @@ static void dma_pl330_rqcb(void *token, enum pl330_op_err err)
 	tasklet_schedule(&pch->task);
 }
 
+bool pl330_filter(struct dma_chan *chan, void *param)
+{
+	struct dma_pl330_peri *peri;
+
+	if (chan->device->dev->driver != &pl330_driver.drv)
+		return false;
+
+	peri = chan->private;
+	return peri->peri_id == (unsigned)param;
+}
+EXPORT_SYMBOL(pl330_filter);
+
 static int pl330_alloc_chan_resources(struct dma_chan *chan)
 {
 	struct dma_pl330_chan *pch = to_pchan(chan);
include/linux/amba/pl330.h +2 -0
index d12f077..6db72da 100644
@@ -12,6 +12,7 @@
 #ifndef	__AMBA_PL330_H_
 #define	__AMBA_PL330_H_
 
+#include <linux/dmaengine.h>
 #include <asm/hardware/pl330.h>
 
 struct dma_pl330_peri {
@@ -38,4 +39,5 @@ struct dma_pl330_platdata {
 	unsigned mcbuf_sz;
 };
 
+extern bool pl330_filter(struct dma_chan *chan, void *param);
 #endif	/* __AMBA_PL330_H_ */
Signature · 1 line
1.6.6.rc2
#2 lore raw

PATCH v2 2/6 DMA: PL330: Infer transfer direction from transfer request instead of platform data

The transfer direction for a channel can be inferred from the transfer request and the need for specifying transfer direction in platfrom data can be eliminated. So the structure definition 'struct dma_pl330_peri' is no longer required.

The channel's private data is set to point to a channel id specified in the platform data (instead of an instance of type 'struct dma_pl330_peri'). The filter function is correspondingly modified to match the channel id.

With the 'struct dma_pl330_peri' removed from platform data, the dma controller transfer capabilities cannot be inferred any more. Hence, the dma controller capabilities is specified using platform data.

---
 drivers/dma/pl330.c        |   65 +++++++++++---------------------------------
 include/linux/amba/pl330.h |   13 ++-------
 2 files changed, 19 insertions(+), 59 deletions(-)
drivers/dma/pl330.c +16 -49
index 7df2516..9732995 100644
@@ -272,13 +272,13 @@ static void dma_pl330_rqcb(void *token, enum pl330_op_err err)
 
 bool pl330_filter(struct dma_chan *chan, void *param)
 {
-	struct dma_pl330_peri *peri;
+	u8 *peri_id;
 
 	if (chan->device->dev->driver != &pl330_driver.drv)
 		return false;
 
-	peri = chan->private;
-	return peri->peri_id == (unsigned)param;
+	peri_id = chan->private;
+	return *peri_id == (unsigned)param;
 }
 EXPORT_SYMBOL(pl330_filter);
 
@@ -514,7 +514,7 @@ pluck_desc(struct dma_pl330_dmac *pdmac)
 static struct dma_pl330_desc *pl330_get_desc(struct dma_pl330_chan *pch)
 {
 	struct dma_pl330_dmac *pdmac = pch->dmac;
-	struct dma_pl330_peri *peri = pch->chan.private;
+	u8 *peri_id = pch->chan.private;
 	struct dma_pl330_desc *desc;
 
 	/* Pluck one desc from the pool of DMAC */
@@ -539,13 +539,7 @@ static struct dma_pl330_desc *pl330_get_desc(struct dma_pl330_chan *pch)
 	desc->txd.cookie = 0;
 	async_tx_ack(&desc->txd);
 
-	if (peri) {
-		desc->req.rqtype = peri->rqtype;
-		desc->req.peri = pch->chan.chan_id;
-	} else {
-		desc->req.rqtype = MEMTOMEM;
-		desc->req.peri = 0;
-	}
+	desc->req.peri = peri_id ? pch->chan.chan_id : 0;
 
 	dma_async_tx_descriptor_init(&desc->txd, &pch->chan);
 
@@ -632,12 +626,14 @@ static struct dma_async_tx_descriptor *pl330_prep_dma_cyclic(
 	case DMA_TO_DEVICE:
 		desc->rqcfg.src_inc = 1;
 		desc->rqcfg.dst_inc = 0;
+		desc->req.rqtype = MEMTODEV;
 		src = dma_addr;
 		dst = pch->fifo_addr;
 		break;
 	case DMA_FROM_DEVICE:
 		desc->rqcfg.src_inc = 0;
 		desc->rqcfg.dst_inc = 1;
+		desc->req.rqtype = DEVTOMEM;
 		src = pch->fifo_addr;
 		dst = dma_addr;
 		break;
@@ -663,16 +659,12 @@ pl330_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dst,
 {
 	struct dma_pl330_desc *desc;
 	struct dma_pl330_chan *pch = to_pchan(chan);
-	struct dma_pl330_peri *peri = chan->private;
 	struct pl330_info *pi;
 	int burst;
 
 	if (unlikely(!pch || !len))
 		return NULL;
 
-	if (peri && peri->rqtype != MEMTOMEM)
-		return NULL;
-
 	pi = &pch->dmac->pif;
 
 	desc = __pl330_prep_dma_memcpy(pch, dst, src, len);
@@ -681,6 +673,7 @@ pl330_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dst,
 
 	desc->rqcfg.src_inc = 1;
 	desc->rqcfg.dst_inc = 1;
+	desc->req.rqtype = MEMTOMEM;
 
 	/* Select max possible burst size */
 	burst = pi->pcfg.data_bus_width / 8;
@@ -709,24 +702,13 @@ pl330_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
 {
 	struct dma_pl330_desc *first, *desc = NULL;
 	struct dma_pl330_chan *pch = to_pchan(chan);
-	struct dma_pl330_peri *peri = chan->private;
 	struct scatterlist *sg;
 	unsigned long flags;
 	int i;
 	dma_addr_t addr;
 
-	if (unlikely(!pch || !sgl || !sg_len || !peri))
-		return NULL;
-
-	/* Make sure the direction is consistent */
-	if ((direction == DMA_TO_DEVICE &&
-				peri->rqtype != MEMTODEV) ||
-			(direction == DMA_FROM_DEVICE &&
-				peri->rqtype != DEVTOMEM)) {
-		dev_err(pch->dmac->pif.dev, "%s:%d Invalid Direction\n",
-				__func__, __LINE__);
+	if (unlikely(!pch || !sgl || !sg_len))
 		return NULL;
-	}
 
 	addr = pch->fifo_addr;
 
@@ -767,11 +749,13 @@ pl330_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
 		if (direction == DMA_TO_DEVICE) {
 			desc->rqcfg.src_inc = 1;
 			desc->rqcfg.dst_inc = 0;
+			desc->req.rqtype = MEMTODEV;
 			fill_px(&desc->px,
 				addr, sg_dma_address(sg), sg_dma_len(sg));
 		} else {
 			desc->rqcfg.src_inc = 0;
 			desc->rqcfg.dst_inc = 1;
+			desc->req.rqtype = DEVTOMEM;
 			fill_px(&desc->px,
 				sg_dma_address(sg), addr, sg_dma_len(sg));
 		}
@@ -878,28 +862,7 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id)
 
 	for (i = 0; i < num_chan; i++) {
 		pch = &pdmac->peripherals[i];
-		if (pdat) {
-			struct dma_pl330_peri *peri = &pdat->peri[i];
-
-			switch (peri->rqtype) {
-			case MEMTOMEM:
-				dma_cap_set(DMA_MEMCPY, pd->cap_mask);
-				break;
-			case MEMTODEV:
-			case DEVTOMEM:
-				dma_cap_set(DMA_SLAVE, pd->cap_mask);
-				dma_cap_set(DMA_CYCLIC, pd->cap_mask);
-				break;
-			default:
-				dev_err(&adev->dev, "DEVTODEV Not Supported\n");
-				continue;
-			}
-			pch->chan.private = peri;
-		} else {
-			dma_cap_set(DMA_MEMCPY, pd->cap_mask);
-			pch->chan.private = NULL;
-		}
-
+		pch->chan.private = pdat ? &pdat->peri_id[i] : NULL;
 		INIT_LIST_HEAD(&pch->work_list);
 		spin_lock_init(&pch->lock);
 		pch->pl330_chid = NULL;
@@ -913,6 +876,10 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id)
 	}
 
 	pd->dev = &adev->dev;
+	if (pdat)
+		pd->cap_mask = pdat->cap_mask;
+	else
+		dma_cap_set(DMA_MEMCPY, pd->cap_mask);
 
 	pd->device_alloc_chan_resources = pl330_alloc_chan_resources;
 	pd->device_free_chan_resources = pl330_free_chan_resources;
include/linux/amba/pl330.h +3 -10
index 6db72da..12e023c 100644
@@ -15,15 +15,6 @@
 #include <linux/dmaengine.h>
 #include <asm/hardware/pl330.h>
 
-struct dma_pl330_peri {
-	/*
-	 * Peri_Req i/f of the DMAC that is
-	 * peripheral could be reached from.
-	 */
-	u8 peri_id; /* specific dma id */
-	enum pl330_reqtype rqtype;
-};
-
 struct dma_pl330_platdata {
 	/*
 	 * Number of valid peripherals connected to DMAC.
@@ -34,7 +25,9 @@ struct dma_pl330_platdata {
 	 */
 	u8 nr_valid_peri;
 	/* Array of valid peripherals */
-	struct dma_pl330_peri *peri;
+	u8 *peri_id;
+	/* Operational capabilities */
+	dma_cap_mask_t cap_mask;
 	/* Bytes to allocate for MC buffer */
 	unsigned mcbuf_sz;
 };
Signature · 1 line
1.6.6.rc2
#3 lore raw

PATCH v2 3/6 ARM: EXYNOS4: Modify platform data for pl330 driver

With the 'struct dma_pl330_peri' removed, the platfrom data for dma driver can be simplified to a simple list of peripheral request ids.

---
 arch/arm/mach-exynos4/dma.c |  223 ++++++++++++-------------------------------
 1 files changed, 62 insertions(+), 161 deletions(-)
arch/arm/mach-exynos4/dma.c +62 -161
index 9667c61..c3c0d17 100644
@@ -35,95 +35,40 @@
 
 static u64 dma_dmamask = DMA_BIT_MASK(32);
 
-struct dma_pl330_peri pdma0_peri[28] = {
-	{
-		.peri_id = (u8)DMACH_PCM0_RX,
-		.rqtype = DEVTOMEM,
-	}, {
-		.peri_id = (u8)DMACH_PCM0_TX,
-		.rqtype = MEMTODEV,
-	}, {
-		.peri_id = (u8)DMACH_PCM2_RX,
-		.rqtype = DEVTOMEM,
-	}, {
-		.peri_id = (u8)DMACH_PCM2_TX,
-		.rqtype = MEMTODEV,
-	}, {
-		.peri_id = (u8)DMACH_MSM_REQ0,
-	}, {
-		.peri_id = (u8)DMACH_MSM_REQ2,
-	}, {
-		.peri_id = (u8)DMACH_SPI0_RX,
-		.rqtype = DEVTOMEM,
-	}, {
-		.peri_id = (u8)DMACH_SPI0_TX,
-		.rqtype = MEMTODEV,
-	}, {
-		.peri_id = (u8)DMACH_SPI2_RX,
-		.rqtype = DEVTOMEM,
-	}, {
-		.peri_id = (u8)DMACH_SPI2_TX,
-		.rqtype = MEMTODEV,
-	}, {
-		.peri_id = (u8)DMACH_I2S0S_TX,
-		.rqtype = MEMTODEV,
-	}, {
-		.peri_id = (u8)DMACH_I2S0_RX,
-		.rqtype = DEVTOMEM,
-	}, {
-		.peri_id = (u8)DMACH_I2S0_TX,
-		.rqtype = MEMTODEV,
-	}, {
-		.peri_id = (u8)DMACH_UART0_RX,
-		.rqtype = DEVTOMEM,
-	}, {
-		.peri_id = (u8)DMACH_UART0_TX,
-		.rqtype = MEMTODEV,
-	}, {
-		.peri_id = (u8)DMACH_UART2_RX,
-		.rqtype = DEVTOMEM,
-	}, {
-		.peri_id = (u8)DMACH_UART2_TX,
-		.rqtype = MEMTODEV,
-	}, {
-		.peri_id = (u8)DMACH_UART4_RX,
-		.rqtype = DEVTOMEM,
-	}, {
-		.peri_id = (u8)DMACH_UART4_TX,
-		.rqtype = MEMTODEV,
-	}, {
-		.peri_id = (u8)DMACH_SLIMBUS0_RX,
-		.rqtype = DEVTOMEM,
-	}, {
-		.peri_id = (u8)DMACH_SLIMBUS0_TX,
-		.rqtype = MEMTODEV,
-	}, {
-		.peri_id = (u8)DMACH_SLIMBUS2_RX,
-		.rqtype = DEVTOMEM,
-	}, {
-		.peri_id = (u8)DMACH_SLIMBUS2_TX,
-		.rqtype = MEMTODEV,
-	}, {
-		.peri_id = (u8)DMACH_SLIMBUS4_RX,
-		.rqtype = DEVTOMEM,
-	}, {
-		.peri_id = (u8)DMACH_SLIMBUS4_TX,
-		.rqtype = MEMTODEV,
-	}, {
-		.peri_id = (u8)DMACH_AC97_MICIN,
-		.rqtype = DEVTOMEM,
-	}, {
-		.peri_id = (u8)DMACH_AC97_PCMIN,
-		.rqtype = DEVTOMEM,
-	}, {
-		.peri_id = (u8)DMACH_AC97_PCMOUT,
-		.rqtype = MEMTODEV,
-	},
+u8 pdma0_peri[] = {
+	DMACH_PCM0_RX,
+	DMACH_PCM0_TX,
+	DMACH_PCM2_RX,
+	DMACH_PCM2_TX,
+	DMACH_MSM_REQ0,
+	DMACH_MSM_REQ2,
+	DMACH_SPI0_RX,
+	DMACH_SPI0_TX,
+	DMACH_SPI2_RX,
+	DMACH_SPI2_TX,
+	DMACH_I2S0S_TX,
+	DMACH_I2S0_RX,
+	DMACH_I2S0_TX,
+	DMACH_UART0_RX,
+	DMACH_UART0_TX,
+	DMACH_UART2_RX,
+	DMACH_UART2_TX,
+	DMACH_UART4_RX,
+	DMACH_UART4_TX,
+	DMACH_SLIMBUS0_RX,
+	DMACH_SLIMBUS0_TX,
+	DMACH_SLIMBUS2_RX,
+	DMACH_SLIMBUS2_TX,
+	DMACH_SLIMBUS4_RX,
+	DMACH_SLIMBUS4_TX,
+	DMACH_AC97_MICIN,
+	DMACH_AC97_PCMIN,
+	DMACH_AC97_PCMOUT,
 };
 
 struct dma_pl330_platdata exynos4_pdma0_pdata = {
 	.nr_valid_peri = ARRAY_SIZE(pdma0_peri),
-	.peri = pdma0_peri,
+	.peri_id = pdma0_peri,
 };
 
 struct amba_device exynos4_device_pdma0 = {
@@ -142,86 +87,37 @@ struct amba_device exynos4_device_pdma0 = {
 	.periphid = 0x00041330,
 };
 
-struct dma_pl330_peri pdma1_peri[25] = {
-	{
-		.peri_id = (u8)DMACH_PCM0_RX,
-		.rqtype = DEVTOMEM,
-	}, {
-		.peri_id = (u8)DMACH_PCM0_TX,
-		.rqtype = MEMTODEV,
-	}, {
-		.peri_id = (u8)DMACH_PCM1_RX,
-		.rqtype = DEVTOMEM,
-	}, {
-		.peri_id = (u8)DMACH_PCM1_TX,
-		.rqtype = MEMTODEV,
-	}, {
-		.peri_id = (u8)DMACH_MSM_REQ1,
-	}, {
-		.peri_id = (u8)DMACH_MSM_REQ3,
-	}, {
-		.peri_id = (u8)DMACH_SPI1_RX,
-		.rqtype = DEVTOMEM,
-	}, {
-		.peri_id = (u8)DMACH_SPI1_TX,
-		.rqtype = MEMTODEV,
-	}, {
-		.peri_id = (u8)DMACH_I2S0S_TX,
-		.rqtype = MEMTODEV,
-	}, {
-		.peri_id = (u8)DMACH_I2S0_RX,
-		.rqtype = DEVTOMEM,
-	}, {
-		.peri_id = (u8)DMACH_I2S0_TX,
-		.rqtype = MEMTODEV,
-	}, {
-		.peri_id = (u8)DMACH_I2S1_RX,
-		.rqtype = DEVTOMEM,
-	}, {
-		.peri_id = (u8)DMACH_I2S1_TX,
-		.rqtype = MEMTODEV,
-	}, {
-		.peri_id = (u8)DMACH_UART0_RX,
-		.rqtype = DEVTOMEM,
-	}, {
-		.peri_id = (u8)DMACH_UART0_TX,
-		.rqtype = MEMTODEV,
-	}, {
-		.peri_id = (u8)DMACH_UART1_RX,
-		.rqtype = DEVTOMEM,
-	}, {
-		.peri_id = (u8)DMACH_UART1_TX,
-		.rqtype = MEMTODEV,
-	}, {
-		.peri_id = (u8)DMACH_UART3_RX,
-		.rqtype = DEVTOMEM,
-	}, {
-		.peri_id = (u8)DMACH_UART3_TX,
-		.rqtype = MEMTODEV,
-	}, {
-		.peri_id = (u8)DMACH_SLIMBUS1_RX,
-		.rqtype = DEVTOMEM,
-	}, {
-		.peri_id = (u8)DMACH_SLIMBUS1_TX,
-		.rqtype = MEMTODEV,
-	}, {
-		.peri_id = (u8)DMACH_SLIMBUS3_RX,
-		.rqtype = DEVTOMEM,
-	}, {
-		.peri_id = (u8)DMACH_SLIMBUS3_TX,
-		.rqtype = MEMTODEV,
-	}, {
-		.peri_id = (u8)DMACH_SLIMBUS5_RX,
-		.rqtype = DEVTOMEM,
-	}, {
-		.peri_id = (u8)DMACH_SLIMBUS5_TX,
-		.rqtype = MEMTODEV,
-	},
+u8 pdma1_peri[] = {
+	DMACH_PCM0_RX,
+	DMACH_PCM0_TX,
+	DMACH_PCM1_RX,
+	DMACH_PCM1_TX,
+	DMACH_MSM_REQ1,
+	DMACH_MSM_REQ3,
+	DMACH_SPI1_RX,
+	DMACH_SPI1_TX,
+	DMACH_I2S0S_TX,
+	DMACH_I2S0_RX,
+	DMACH_I2S0_TX,
+	DMACH_I2S1_RX,
+	DMACH_I2S1_TX,
+	DMACH_UART0_RX,
+	DMACH_UART0_TX,
+	DMACH_UART1_RX,
+	DMACH_UART1_TX,
+	DMACH_UART3_RX,
+	DMACH_UART3_TX,
+	DMACH_SLIMBUS1_RX,
+	DMACH_SLIMBUS1_TX,
+	DMACH_SLIMBUS3_RX,
+	DMACH_SLIMBUS3_TX,
+	DMACH_SLIMBUS5_RX,
+	DMACH_SLIMBUS5_TX,
 };
 
 struct dma_pl330_platdata exynos4_pdma1_pdata = {
 	.nr_valid_peri = ARRAY_SIZE(pdma1_peri),
-	.peri = pdma1_peri,
+	.peri_id = pdma1_peri,
 };
 
 struct amba_device exynos4_device_pdma1 = {
@@ -242,7 +138,12 @@ struct amba_device exynos4_device_pdma1 = {
 
 static int __init exynos4_dma_init(void)
 {
+	dma_cap_set(DMA_SLAVE, exynos4_pdma0_pdata.cap_mask);
+	dma_cap_set(DMA_CYCLIC, exynos4_pdma0_pdata.cap_mask);
 	amba_device_register(&exynos4_device_pdma0, &iomem_resource);
+
+	dma_cap_set(DMA_SLAVE, exynos4_pdma1_pdata.cap_mask);
+	dma_cap_set(DMA_CYCLIC, exynos4_pdma1_pdata.cap_mask);
 	amba_device_register(&exynos4_device_pdma1, &iomem_resource);
 
 	return 0;
Signature · 1 line
1.6.6.rc2
#4 lore raw

PATCH v2 4/6 DMA: PL330: Add device tree support

For PL330 dma controllers instantiated from device tree, the channel lookup is based on phandle of the dma controller and dma request id specified by the client node. During probe, the private data of each channel of the controller is set to point to the device node of the dma controller. The 'chan_id' of the each channel is used as the dma request id.

Client driver requesting dma channels specify the phandle of the dma controller and the request id. The pl330 filter function converts the phandle to the device node pointer and matches that with channel's private data. If a match is found, the request id from the client node and the 'chan_id' of the channel is matched. A channel is found if both the values match.

---
 .../devicetree/bindings/dma/arm-pl330.txt          |   29 ++++++++++++++++
 drivers/dma/pl330.c                                |   35 +++++++++++++++++---
 2 files changed, 59 insertions(+), 5 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/dma/arm-pl330.txt
Documentation/devicetree/bindings/dma/arm-pl330.txt new file +29 -0
new file mode 100644
index 0000000..69e6c02
@@ -0,0 +1,29 @@
+* ARM PrimeCell PL330 DMA Controller
+
+The ARM PrimeCell PL330 DMA controller can move blocks of memory contents
+between memory and peripherals or memory to memory.
+
+Required properties:
+  - compatible: should include both "arm,pl330" and "arm,primecell".
+  - reg: physical base address of the controller and length of memory mapped
+    region.
+  - interrupts: interrupt number to the cpu.
+
+Example: (from Samsung's Exynos4 processor dtsi file)
+
+	pdma0: pdma at 12680000 {
+		compatible = "arm,pl330", "arm,primecell";
+		reg = <0x12680000 0x1000>;
+		interrupts = <99>;
+	};
+
+Client drivers (device nodes requiring dma transfers from dev-to-mem or
+mem-to-dev) should specify the DMA channel numbers using a two-value pair
+as shown below.
+
+  [property name]  = <[phandle of the dma controller] [dma request id]>;
+
+      where 'dma request id' is the dma request number which is connected
+      to the client controller.
+
+  Example:  tx-dma-channel = <&pdma0 12>;
drivers/dma/pl330.c +30 -5
index 9732995..0c55de4 100644
@@ -19,6 +19,7 @@
 #include <linux/amba/pl330.h>
 #include <linux/pm_runtime.h>
 #include <linux/scatterlist.h>
+#include <linux/of.h>
 
 #define NR_DEFAULT_DESC	16
 
@@ -277,6 +278,20 @@ bool pl330_filter(struct dma_chan *chan, void *param)
 	if (chan->device->dev->driver != &pl330_driver.drv)
 		return false;
 
+#ifdef CONFIG_OF
+	if (chan->device->dev->of_node) {
+		const __be32 *prop_value;
+		phandle phandle;
+		struct device_node *node;
+
+		prop_value = ((struct property *)param)->value;
+		phandle = be32_to_cpup(prop_value++);
+		node = of_find_node_by_phandle(phandle);
+		return ((chan->private == node) &&
+				(chan->chan_id == be32_to_cpup(prop_value)));
+	}
+#endif
+
 	peri_id = chan->private;
 	return *peri_id == (unsigned)param;
 }
@@ -857,12 +872,17 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id)
 	INIT_LIST_HEAD(&pd->channels);
 
 	/* Initialize channel parameters */
-	num_chan = max(pdat ? pdat->nr_valid_peri : 0, (u8)pi->pcfg.num_chan);
+	num_chan = max(pdat ? pdat->nr_valid_peri : (u8)pi->pcfg.num_peri,
+			(u8)pi->pcfg.num_chan);
 	pdmac->peripherals = kzalloc(num_chan * sizeof(*pch), GFP_KERNEL);
 
 	for (i = 0; i < num_chan; i++) {
 		pch = &pdmac->peripherals[i];
-		pch->chan.private = pdat ? &pdat->peri_id[i] : NULL;
+		if (!adev->dev.of_node)
+			pch->chan.private = pdat ? &pdat->peri_id[i] : NULL;
+		else
+			pch->chan.private = adev->dev.of_node;
+
 		INIT_LIST_HEAD(&pch->work_list);
 		spin_lock_init(&pch->lock);
 		pch->pl330_chid = NULL;
@@ -876,11 +896,16 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id)
 	}
 
 	pd->dev = &adev->dev;
-	if (pdat)
+	if (pdat) {
 		pd->cap_mask = pdat->cap_mask;
-	else
+	} else {
 		dma_cap_set(DMA_MEMCPY, pd->cap_mask);
-
+		if (pi->pcfg.num_peri) {
+			dma_cap_set(DMA_SLAVE, pd->cap_mask);
+			dma_cap_set(DMA_CYCLIC, pd->cap_mask);
+		}
+	}
+
 	pd->device_alloc_chan_resources = pl330_alloc_chan_resources;
 	pd->device_free_chan_resources = pl330_free_chan_resources;
 	pd->device_prep_dma_memcpy = pl330_prep_dma_memcpy;
Signature · 1 line
1.6.6.rc2
#5 lore raw

PATCH v2 5/6 ARM: SAMSUNG: Add device tree support for pl330 dma engine wrappers

A new dma request id 'DMACH_DT_PROP' is introduced for client drivers requesting a dma channel. This request indicates that a device tree node property represting the dma channel is available in 'struct samsung_dma_info'. The dma channel request wrapper uses the node property value as the value for the filter parameter.

---
 arch/arm/plat-samsung/dma-ops.c                |    9 ++++++++-
 arch/arm/plat-samsung/include/plat/dma-ops.h   |    1 +
 arch/arm/plat-samsung/include/plat/dma-pl330.h |    3 ++-
 3 files changed, 11 insertions(+), 2 deletions(-)
arch/arm/plat-samsung/dma-ops.c +8 -1
index 8d18425..b1135dd 100644
@@ -23,11 +23,18 @@ static unsigned samsung_dmadev_request(enum dma_ch dma_ch,
 	struct dma_chan *chan;
 	dma_cap_mask_t mask;
 	struct dma_slave_config slave_config;
+	void *filter_param;
 
 	dma_cap_zero(mask);
 	dma_cap_set(info->cap, mask);
 
-	chan = dma_request_channel(mask, pl330_filter, (void *)dma_ch);
+	/*
+	 * If a dma channel property of a device node from device tree is
+	 * specified, use that as the fliter parameter.
+	 */
+	filter_param = (dma_ch == DMACH_DT_PROP) ? (void *)info->dt_dmach_prop :
+				(void *)dma_ch;
+	chan = dma_request_channel(mask, pl330_filter, filter_param);
 
 	if (info->direction == DMA_FROM_DEVICE) {
 		memset(&slave_config, 0, sizeof(struct dma_slave_config));
arch/arm/plat-samsung/include/plat/dma-ops.h +1 -0
index 4c1a363..22eafc3 100644
@@ -31,6 +31,7 @@ struct samsung_dma_info {
 	enum dma_slave_buswidth width;
 	dma_addr_t fifo;
 	struct s3c2410_dma_client *client;
+	struct property *dt_dmach_prop;
 };
 
 struct samsung_dma_ops {
arch/arm/plat-samsung/include/plat/dma-pl330.h +2 -1
index 2e55e59..c5eaad5 100644
@@ -21,7 +21,8 @@
  * use these just as IDs.
  */
 enum dma_ch {
-	DMACH_UART0_RX,
+	DMACH_DT_PROP = -1,
+	DMACH_UART0_RX = 0,
 	DMACH_UART0_TX,
 	DMACH_UART1_RX,
 	DMACH_UART1_TX,
Signature · 1 line
1.6.6.rc2
#6 lore raw

PATCH v2 6/6 ARM: EXYNOS4: Limit usage of pl330 device instance to non-dt build

The pl330 device instances and associated platform data is required only for non-device-tree builds. With device tree, all of this information is obtained from the device tree.

---
 arch/arm/mach-exynos4/Kconfig  |    7 +++++++
 arch/arm/mach-exynos4/Makefile |    3 ++-
 2 files changed, 9 insertions(+), 1 deletions(-)
arch/arm/mach-exynos4/Kconfig +7 -0
index d4d401c..3edbf37 100644
@@ -21,6 +21,13 @@ config EXYNOS4_MCT
 	help
 	  Use MCT (Multi Core Timer) as kernel timers
 
+config EXYNOS4_DEV_DMA
+	bool
+	default y if !OF
+	help
+	  Compile in amba device definitions for DMA controller if OF
+	  is not enabled.
+
 config EXYNOS4_DEV_AHCI
 	bool
 	help
arch/arm/mach-exynos4/Makefile +2 -1
index d2bf5bf..a2f33dc 100644
@@ -13,7 +13,8 @@ obj-				:=
 # Core support for EXYNOS4 system
 
 obj-$(CONFIG_CPU_EXYNOS4210)	+= cpu.o init.o clock.o irq-combiner.o
-obj-$(CONFIG_CPU_EXYNOS4210)	+= setup-i2c0.o irq-eint.o dma.o pmu.o
+obj-$(CONFIG_CPU_EXYNOS4210)	+= setup-i2c0.o irq-eint.o pmu.o
+obj-$(CONFIG_EXYNOS4_DEV_DMA)	+= dma.o
 obj-$(CONFIG_PM)		+= pm.o sleep.o
 obj-$(CONFIG_CPU_IDLE)		+= cpuidle.o
 
Signature · 1 line
1.6.6.rc2
#7 lore raw

PATCH v2 6/6 ARM: EXYNOS4: Limit usage of pl330 device instance to non-dt build

Quoted 5 lines

-----Original Message-----
From: Thomas Abraham [mailto:thomas.abraham at linaro.org]
Sent: Thursday, September 01, 2011 6:05 PM
To: devicetree-discuss at lists.ozlabs.org
Cc: grant.likely at secretlab.ca; linux-arm-kernel at lists.infradead.org;

linux-samsung-

Quoted 4 lines

soc at vger.kernel.org; kgene.kim at samsung.com; robherring2 at gmail.com; vinod.koul at intel.com; patches at linaro.org; jassisinghbrar at gmail.com; boojin.kim at samsung.com
Subject: [PATCH v2 6/6] ARM: EXYNOS4: Limit usage of pl330 device instance

to

Review

Quoted 31 lines

non-dt build

The pl330 device instances and associated platform data is required only for non-device-tree builds. With device tree, all of this information is obtained from the device tree.

---
 arch/arm/mach-exynos4/Kconfig  |    7 +++++++
 arch/arm/mach-exynos4/Makefile |    3 ++-
 2 files changed, 9 insertions(+), 1 deletions(-)
arch/arm/mach-exynos4/Kconfig +7 -0
index d4d401c..3edbf37 100644
@@ -21,6 +21,13 @@ config EXYNOS4_MCT
 	help
 	  Use MCT (Multi Core Timer) as kernel timers
 
+config EXYNOS4_DEV_DMA
+	bool
+	default y if !OF
+	help
+	  Compile in amba device definitions for DMA controller if OF
+	  is not enabled.
+
 config EXYNOS4_DEV_AHCI
 	bool
 	help
(quoted diff) +0 -0

b/arch/arm/mach-exynos4/Makefile

arch/arm/mach-exynos4/Makefile obj- := · line 17

Quoted 11 lines

index d2bf5bf..a2f33dc 100644

arch/arm/mach-exynos4/Makefile +0 -1
@@ -13,7 +13,8 @@ obj-				:=
 # Core support for EXYNOS4 system
 
 obj-$(CONFIG_CPU_EXYNOS4210)	+= cpu.o init.o clock.o irq-combiner.o
-obj-$(CONFIG_CPU_EXYNOS4210)	+= setup-i2c0.o irq-eint.o dma.o

pmu.o

arch/arm/mach-exynos4/Makefile +2 -0
+obj-$(CONFIG_CPU_EXYNOS4210)	+= setup-i2c0.o irq-eint.o pmu.o
+obj-$(CONFIG_EXYNOS4_DEV_DMA)	+= dma.o

Do we need _really_ EXYNOS4_DEV_DMA here?
How about to use like following?

+obj-$(!CONFIG_OF) += dma.o

If any problems, let me know.

Thanks.

Best regards,
Kgene.
--
Kukjin Kim <[email protected]>, Senior Engineer, SW Solution Development Team, Samsung Electronics Co., Ltd.

Quoted 5 lines

obj-$(CONFIG_PM) += pm.o sleep.o
obj-$(CONFIG_CPU_IDLE) += cpuidle.o

--
1.6.6.rc2

#8 lore raw

PATCH v2 6/6 ARM: EXYNOS4: Limit usage of pl330 device instance to non-dt build

Dear Mr. Kim,

Quoted 58 lines · Kukjin Kim
Quoted 5 lines

-----Original Message-----
From: Thomas Abraham [mailto:thomas.abraham at linaro.org]
Sent: Thursday, September 01, 2011 6:05 PM
To: devicetree-discuss at lists.ozlabs.org
Cc: grant.likely at secretlab.ca; linux-arm-kernel at lists.infradead.org;

linux-samsung-

Quoted 4 lines

soc at vger.kernel.org; kgene.kim at samsung.com; robherring2 at gmail.com; vinod.koul at intel.com; patches at linaro.org; jassisinghbrar at gmail.com; boojin.kim at samsung.com
Subject: [PATCH v2 6/6] ARM: EXYNOS4: Limit usage of pl330 device instance

to

Quoted 30 lines

non-dt build

The pl330 device instances and associated platform data is required only for non-device-tree builds. With device tree, all of this information is obtained from the device tree.

---
?arch/arm/mach-exynos4/Kconfig ?| ? ?7 +++++++
?arch/arm/mach-exynos4/Makefile | ? ?3 ++-
?2 files changed, 9 insertions(+), 1 deletions(-)

arch/arm/mach-exynos4/Kconfig +0 -0
index d4d401c..3edbf37 100644
@@ -21,6 +21,13 @@ config EXYNOS4_MCT

? ? ? help
? ? ? ? Use MCT (Multi Core Timer) as kernel timers

arch/arm/mach-exynos4/Kconfig +7 -0
+config EXYNOS4_DEV_DMA
+ ? ? bool
+ ? ? default y if !OF
+ ? ? help
+ ? ? ? Compile in amba device definitions for DMA controller if OF
+ ? ? ? is not enabled.
+

?config EXYNOS4_DEV_AHCI
? ? ? bool
? ? ? help

Review

Quoted 1 line
(quoted diff) +0 -0

b/arch/arm/mach-exynos4/Makefile

arch/arm/mach-exynos4/Makefile

Quoted 11 lines

index d2bf5bf..a2f33dc 100644

arch/arm/mach-exynos4/Makefile +0 -0
@@ -13,7 +13,8 @@ obj- ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?:=

?# Core support for EXYNOS4 system

?obj-$(CONFIG_CPU_EXYNOS4210) += cpu.o init.o clock.o irq-combiner.o -obj-$(CONFIG_CPU_EXYNOS4210) += setup-i2c0.o irq-eint.o dma.o pmu.o

arch/arm/mach-exynos4/Makefile +2 -0
+obj-$(CONFIG_CPU_EXYNOS4210) += setup-i2c0.o irq-eint.o pmu.o
+obj-$(CONFIG_EXYNOS4_DEV_DMA) ? ? ? ?+= dma.o

Do we need _really_ EXYNOS4_DEV_DMA here?
How about to use like following?

Quoted 1 line

+obj-$(!CONFIG_OF) ? ? ? ? ? ? ?+= dma.o

Thanks for the suggestion. I will try it and resubmit the patch.

Thanks,
Thomas.

Quoted 19 lines

If any problems, let me know.

Thanks.

Best regards,
Kgene.
--
Kukjin Kim <[email protected]>, Senior Engineer, SW Solution Development Team, Samsung Electronics Co., Ltd.

Quoted 5 lines

?obj-$(CONFIG_PM) ? ? ? ? ? ? += pm.o sleep.o ?obj-$(CONFIG_CPU_IDLE) ? ? ? ? ? ? ? += cpuidle.o

--
1.6.6.rc2

#9 lore raw

PATCH v2 6/6 ARM: EXYNOS4: Limit usage of pl330 device instance to non-dt build

In reply to Kukjin Kim

Dear Mr. Kim,

Quoted 49 lines · Kukjin Kim
Quoted 1 line

Subject: [PATCH v2 6/6] ARM: EXYNOS4: Limit usage of pl330 device instance

to

Quoted 30 lines

non-dt build

The pl330 device instances and associated platform data is required only for non-device-tree builds. With device tree, all of this information is obtained from the device tree.

---
?arch/arm/mach-exynos4/Kconfig ?| ? ?7 +++++++
?arch/arm/mach-exynos4/Makefile | ? ?3 ++-
?2 files changed, 9 insertions(+), 1 deletions(-)

arch/arm/mach-exynos4/Kconfig +0 -0
index d4d401c..3edbf37 100644
@@ -21,6 +21,13 @@ config EXYNOS4_MCT

? ? ? help
? ? ? ? Use MCT (Multi Core Timer) as kernel timers

arch/arm/mach-exynos4/Kconfig +7 -0
+config EXYNOS4_DEV_DMA
+ ? ? bool
+ ? ? default y if !OF
+ ? ? help
+ ? ? ? Compile in amba device definitions for DMA controller if OF
+ ? ? ? is not enabled.
+

?config EXYNOS4_DEV_AHCI
? ? ? bool
? ? ? help

Review

Quoted 1 line
(quoted diff) +0 -0

b/arch/arm/mach-exynos4/Makefile

arch/arm/mach-exynos4/Makefile

Quoted 11 lines

index d2bf5bf..a2f33dc 100644

arch/arm/mach-exynos4/Makefile +0 -0
@@ -13,7 +13,8 @@ obj- ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?:=

?# Core support for EXYNOS4 system

?obj-$(CONFIG_CPU_EXYNOS4210) += cpu.o init.o clock.o irq-combiner.o -obj-$(CONFIG_CPU_EXYNOS4210) += setup-i2c0.o irq-eint.o dma.o pmu.o

arch/arm/mach-exynos4/Makefile +2 -0
+obj-$(CONFIG_CPU_EXYNOS4210) += setup-i2c0.o irq-eint.o pmu.o
+obj-$(CONFIG_EXYNOS4_DEV_DMA) ? ? ? ?+= dma.o

Do we need _really_ EXYNOS4_DEV_DMA here?
How about to use like following?

Quoted 3 lines

+obj-$(!CONFIG_OF) ? ? ? ? ? ? ?+= dma.o

If any problems, let me know.

While trying out your suggestion, I found a issue with this patch related to compiling a kernel with both dt and non-dt board files included in the build.

When compiling a single kernel image with mach-smdkv310.c file and exynos4 device tree enabled machine file, since CONFIG_OF is enabled, dma platform data does not get compiled which is required for mach-smdkv310. So, I would like to resubmit this patch and the updated diff is listed below. Could you please review the following diff.

arch/arm/mach-exynos4/Kconfig +9 -0
index d4d401c..953ead7 100644
@@ -21,6 +21,11 @@ config EXYNOS4_MCT
 	help
 	  Use MCT (Multi Core Timer) as kernel timers
 
+config EXYNOS4_DEV_DMA
+	bool
+	help
+	  Compile in amba device definitions for DMA controller
+
 config EXYNOS4_DEV_AHCI
 	bool
 	help
@@ -129,6 +134,7 @@ config MACH_SMDKC210
 	select EXYNOS4_SETUP_FIMD0
 	select EXYNOS4_SETUP_I2C1
 	select EXYNOS4_SETUP_SDHCI
+	select EXYNOS4_DEV_DMA
 	help
 	  Machine support for Samsung SMDKC210
 
@@ -153,6 +159,7 @@ config MACH_SMDKV310
 	select EXYNOS4_SETUP_I2C1
 	select EXYNOS4_SETUP_KEYPAD
 	select EXYNOS4_SETUP_SDHCI
+	select EXYNOS4_DEV_DMA
 	help
 	  Machine support for Samsung SMDKV310
 
@@ -191,6 +198,7 @@ config MACH_UNIVERSAL_C210
 	select EXYNOS4_SETUP_I2C3
 	select EXYNOS4_SETUP_I2C5
 	select EXYNOS4_SETUP_SDHCI
+	select EXYNOS4_DEV_DMA
 	help
 	  Machine support for Samsung Mobile Universal S5PC210 Reference
 	  Board.
@@ -215,6 +223,7 @@ config MACH_NURI
 	select EXYNOS4_SETUP_USB_PHY
 	select SAMSUNG_DEV_PWM
 	select SAMSUNG_DEV_ADC
+	select EXYNOS4_DEV_DMA
 	help
 	  Machine support for Samsung Mobile NURI Board.
 
arch/arm/mach-exynos4/Makefile +2 -1
index 929262a..a2f33dc 100644
@@ -14,7 +14,8 @@ obj-				:=
 
 obj-$(CONFIG_CPU_EXYNOS4210)	+= cpu.o init.o clock.o irq-combiner.o
-obj-$(CONFIG_CPU_EXYNOS4210)	+= setup-i2c0.o irq-eint.o dma.o pmu.o
+obj-$(CONFIG_CPU_EXYNOS4210)	+= setup-i2c0.o irq-eint.o pmu.o
+obj-$(CONFIG_EXYNOS4_DEV_DMA)	+= dma.o
 obj-$(CONFIG_PM)		+= pm.o sleep.o
 obj-$(CONFIG_CPU_IDLE)		+= cpuidle.o
 
 

Thanks,
Thomas.

#10 lore raw

PATCH v2 6/6 ARM: EXYNOS4: Limit usage of pl330 device instance to non-dt build

Quoted 5 lines · Thomas Abraham

Dear Mr. Kim,

Quoted 1 line · Kukjin Kim
Quoted 1 line

Subject: [PATCH v2 6/6] ARM: EXYNOS4: Limit usage of pl330 device

instance

Quoted 4 lines
Quoted 4 lines

to

Quoted 3 lines

non-dt build

The pl330 device instances and associated platform data is required

only

Quoted 1 line
Quoted 1 line
Quoted 1 line

for non-device-tree builds. With device tree, all of this information

is

Quoted 9 lines
Quoted 9 lines

Review

Quoted 9 lines

obtained from the device tree.

---
?arch/arm/mach-exynos4/Kconfig ?| ? ?7 +++++++
?arch/arm/mach-exynos4/Makefile | ? ?3 ++-
?2 files changed, 9 insertions(+), 1 deletions(-)

(quoted diff) +0 -0

b/arch/arm/mach-exynos4/Kconfig

Quoted 42 lines
Quoted 34 lines
Quoted 17 lines

index d4d401c..3edbf37 100644

arch/arm/mach-exynos4/Kconfig +0 -0
@@ -21,6 +21,13 @@ config EXYNOS4_MCT

? ? ? help
? ? ? ? Use MCT (Multi Core Timer) as kernel timers

arch/arm/mach-exynos4/Kconfig +7 -0
+config EXYNOS4_DEV_DMA
+ ? ? bool
+ ? ? default y if !OF
+ ? ? help
+ ? ? ? Compile in amba device definitions for DMA controller if OF
+ ? ? ? is not enabled.
+

?config EXYNOS4_DEV_AHCI
? ? ? bool
? ? ? help

Review

Quoted 1 line
(quoted diff) +0 -0

b/arch/arm/mach-exynos4/Makefile

arch/arm/mach-exynos4/Makefile

Quoted 11 lines

index d2bf5bf..a2f33dc 100644

arch/arm/mach-exynos4/Makefile +0 -0
@@ -13,7 +13,8 @@ obj- ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?:=

?# Core support for EXYNOS4 system

?obj-$(CONFIG_CPU_EXYNOS4210) += cpu.o init.o clock.o irq-combiner.o -obj-$(CONFIG_CPU_EXYNOS4210) += setup-i2c0.o irq-eint.o dma.o pmu.o

arch/arm/mach-exynos4/Makefile +2 -0
+obj-$(CONFIG_CPU_EXYNOS4210) += setup-i2c0.o irq-eint.o pmu.o
+obj-$(CONFIG_EXYNOS4_DEV_DMA) ? ? ? ?+= dma.o

Do we need _really_ EXYNOS4_DEV_DMA here?
How about to use like following?

Quoted 3 lines

+obj-$(!CONFIG_OF) ? ? ? ? ? ? ?+= dma.o

If any problems, let me know.

While trying out your suggestion, I found a issue with this patch related to compiling a kernel with both dt and non-dt board files included in the build.

Quoted 6 lines

When compiling a single kernel image with mach-smdkv310.c file and exynos4 device tree enabled machine file, since CONFIG_OF is enabled, dma platform data does not get compiled which is required for mach-smdkv310. So, I would like to resubmit this patch and the updated diff is listed below. Could you please review the following diff.

Hi Thomas,

Oops, you're right...so following is ok to me but you need to rebase this based on latest my tree.

If any problems, please let me know.

Thanks.

Best regards,
Kgene.
--
Kukjin Kim <[email protected]>, Senior Engineer, SW Solution Development Team, Samsung Electronics Co., Ltd.

Review

Quoted 50 lines
arch/arm/mach-exynos4/Kconfig +9 -0
index d4d401c..953ead7 100644
@@ -21,6 +21,11 @@ config EXYNOS4_MCT
 	help
 	  Use MCT (Multi Core Timer) as kernel timers
 
+config EXYNOS4_DEV_DMA
+	bool
+	help
+	  Compile in amba device definitions for DMA controller
+
 config EXYNOS4_DEV_AHCI
 	bool
 	help
@@ -129,6 +134,7 @@ config MACH_SMDKC210
 	select EXYNOS4_SETUP_FIMD0
 	select EXYNOS4_SETUP_I2C1
 	select EXYNOS4_SETUP_SDHCI
+	select EXYNOS4_DEV_DMA
 	help
 	  Machine support for Samsung SMDKC210
 
@@ -153,6 +159,7 @@ config MACH_SMDKV310
 	select EXYNOS4_SETUP_I2C1
 	select EXYNOS4_SETUP_KEYPAD
 	select EXYNOS4_SETUP_SDHCI
+	select EXYNOS4_DEV_DMA
 	help
 	  Machine support for Samsung SMDKV310
 
@@ -191,6 +198,7 @@ config MACH_UNIVERSAL_C210
 	select EXYNOS4_SETUP_I2C3
 	select EXYNOS4_SETUP_I2C5
 	select EXYNOS4_SETUP_SDHCI
+	select EXYNOS4_DEV_DMA
 	help
 	  Machine support for Samsung Mobile Universal S5PC210 Reference
 	  Board.
@@ -215,6 +223,7 @@ config MACH_NURI
 	select EXYNOS4_SETUP_USB_PHY
 	select SAMSUNG_DEV_PWM
 	select SAMSUNG_DEV_ADC
+	select EXYNOS4_DEV_DMA
 	help
 	  Machine support for Samsung Mobile NURI Board.
 
(quoted diff) +0 -0

b/arch/arm/mach-exynos4/Makefile

Quoted 17 lines

index 929262a..a2f33dc 100644

arch/arm/mach-exynos4/Makefile +0 -1
@@ -14,7 +14,8 @@ obj-				:=
 
 obj-$(CONFIG_CPU_EXYNOS4210)	+= cpu.o init.o clock.o irq-combiner.o
-obj-$(CONFIG_CPU_EXYNOS4210)	+= setup-i2c0.o irq-eint.o dma.o

pmu.o

arch/arm/mach-exynos4/Makefile +2 -0
+obj-$(CONFIG_CPU_EXYNOS4210)	+= setup-i2c0.o irq-eint.o pmu.o
+obj-$(CONFIG_EXYNOS4_DEV_DMA)	+= dma.o
 obj-$(CONFIG_PM)		+= pm.o sleep.o
 obj-$(CONFIG_CPU_IDLE)		+= cpuidle.o

Thanks,
Thomas.

#11 lore raw

PATCH v2 4/6 DMA: PL330: Add device tree support

In reply to Thomas Abraham
Quoted 14 lines · Thomas Abraham

For PL330 dma controllers instantiated from device tree, the channel lookup is based on phandle of the dma controller and dma request id specified by the client node. During probe, the private data of each channel of the controller is set to point to the device node of the dma controller. The 'chan_id' of the each channel is used as the dma request id.

Client driver requesting dma channels specify the phandle of the dma controller and the request id. The pl330 filter function converts the phandle to the device node pointer and matches that with channel's private data. If a match is found, the request id from the client node and the 'chan_id' of the channel is matched. A channel is found if both the values match.

Quoted 3 lines

Looks good.

Quoted 114 lines
---
 .../devicetree/bindings/dma/arm-pl330.txt          |   29 ++++++++++++++++
 drivers/dma/pl330.c                                |   35 +++++++++++++++++---
 2 files changed, 59 insertions(+), 5 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/dma/arm-pl330.txt
Documentation/devicetree/bindings/dma/arm-pl330.txt new file +29 -0
new file mode 100644
index 0000000..69e6c02
@@ -0,0 +1,29 @@
+* ARM PrimeCell PL330 DMA Controller
+
+The ARM PrimeCell PL330 DMA controller can move blocks of memory contents
+between memory and peripherals or memory to memory.
+
+Required properties:
+  - compatible: should include both "arm,pl330" and "arm,primecell".
+  - reg: physical base address of the controller and length of memory mapped
+    region.
+  - interrupts: interrupt number to the cpu.
+
+Example: (from Samsung's Exynos4 processor dtsi file)
+
+	pdma0: pdma at 12680000 {
+		compatible = "arm,pl330", "arm,primecell";
+		reg = <0x12680000 0x1000>;
+		interrupts = <99>;
+	};
+
+Client drivers (device nodes requiring dma transfers from dev-to-mem or
+mem-to-dev) should specify the DMA channel numbers using a two-value pair
+as shown below.
+
+  [property name]  = <[phandle of the dma controller] [dma request id]>;
+
+      where 'dma request id' is the dma request number which is connected
+      to the client controller.
+
+  Example:  tx-dma-channel = <&pdma0 12>;
drivers/dma/pl330.c +30 -5
index 9732995..0c55de4 100644
@@ -19,6 +19,7 @@
 #include <linux/amba/pl330.h>
 #include <linux/pm_runtime.h>
 #include <linux/scatterlist.h>
+#include <linux/of.h>
 
 #define NR_DEFAULT_DESC	16
 
@@ -277,6 +278,20 @@ bool pl330_filter(struct dma_chan *chan, void *param)
 	if (chan->device->dev->driver != &pl330_driver.drv)
 		return false;
 
+#ifdef CONFIG_OF
+	if (chan->device->dev->of_node) {
+		const __be32 *prop_value;
+		phandle phandle;
+		struct device_node *node;
+
+		prop_value = ((struct property *)param)->value;
+		phandle = be32_to_cpup(prop_value++);
+		node = of_find_node_by_phandle(phandle);
+		return ((chan->private == node) &&
+				(chan->chan_id == be32_to_cpup(prop_value)));
+	}
+#endif
+
 	peri_id = chan->private;
 	return *peri_id == (unsigned)param;
 }
@@ -857,12 +872,17 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id)
 	INIT_LIST_HEAD(&pd->channels);
 
 	/* Initialize channel parameters */
-	num_chan = max(pdat ? pdat->nr_valid_peri : 0, (u8)pi->pcfg.num_chan);
+	num_chan = max(pdat ? pdat->nr_valid_peri : (u8)pi->pcfg.num_peri,
+			(u8)pi->pcfg.num_chan);
 	pdmac->peripherals = kzalloc(num_chan * sizeof(*pch), GFP_KERNEL);
 
 	for (i = 0; i < num_chan; i++) {
 		pch = &pdmac->peripherals[i];
-		pch->chan.private = pdat ? &pdat->peri_id[i] : NULL;
+		if (!adev->dev.of_node)
+			pch->chan.private = pdat ? &pdat->peri_id[i] : NULL;
+		else
+			pch->chan.private = adev->dev.of_node;
+
 		INIT_LIST_HEAD(&pch->work_list);
 		spin_lock_init(&pch->lock);
 		pch->pl330_chid = NULL;
@@ -876,11 +896,16 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id)
 	}
 
 	pd->dev = &adev->dev;
-	if (pdat)
+	if (pdat) {
 		pd->cap_mask = pdat->cap_mask;
-	else
+	} else {
 		dma_cap_set(DMA_MEMCPY, pd->cap_mask);
-
+		if (pi->pcfg.num_peri) {
+			dma_cap_set(DMA_SLAVE, pd->cap_mask);
+			dma_cap_set(DMA_CYCLIC, pd->cap_mask);
+		}
+	}
+
 	pd->device_alloc_chan_resources = pl330_alloc_chan_resources;
 	pd->device_free_chan_resources = pl330_free_chan_resources;
 	pd->device_prep_dma_memcpy = pl330_prep_dma_memcpy;