[PATCH v9 0/4] Add generic driver for on-chip SRAM

[PATCH v9 0/4] Add generic driver for on-chip SRAM

[Philipp Zabel]

These patches add support to configure on-chip SRAM via device-tree
node or platform data and to obtain the resulting genalloc pool from
the struct device pointer or a phandle pointing at the device tree node.
This allows drivers to allocate SRAM with the genalloc API without
hard-coding the genalloc pool pointer.

The on-chip SRAM on i.MX53 and i.MX6q can be registered via device tree
and changed to use the simple generic SRAM driver:

                ocram: ocram@00900000 {
                        compatible = "fsl,imx-ocram", "mmio-sram";
                        reg = <0x00900000 0x3f000>;
                };

A driver that needs to allocate SRAM buffers, like the video processing
unit on i.MX53, can retrieve the genalloc pool from a phandle in the
device tree using of_get_named_gen_pool(node, "iram", 0) from patch 1:

                vpu@63ff4000 {
                        /* ... */
                        iram = <&ocram>;
                };

Changes since v8:
 - The sram driver now matches against the "mmio-sram" compatible string.
 - Removed a whitespace error in the device tree binding documentation.

regards
Philipp

---
 Documentation/devicetree/bindings/media/coda.txt |   30 ++++++
 Documentation/devicetree/bindings/misc/sram.txt  |   16 +++
 arch/arm/boot/dts/imx53.dtsi                     |    5 +
 arch/arm/boot/dts/imx6q.dtsi                     |    6 ++
 drivers/media/platform/Kconfig                   |    1 -
 drivers/media/platform/coda.c                    |   45 +++++---
 drivers/misc/Kconfig                             |    9 ++
 drivers/misc/Makefile                            |    1 +
 drivers/misc/sram.c                              |  121 ++++++++++++++++++++++
 include/linux/genalloc.h                         |   15 +++
 include/linux/platform_data/coda.h               |   18 ++++
 lib/genalloc.c                                   |   81 +++++++++++++++
 12 files changed, 333 insertions(+), 15 deletions(-)

[PATCH v9 1/4] genalloc: add devres support, allow to find a managed pool by device

[Philipp Zabel]

This patch adds three exported functions to lib/genalloc.c:
devm_gen_pool_create, dev_get_gen_pool, and of_get_named_gen_pool.

devm_gen_pool_create is a managed version of gen_pool_create that keeps
track of the pool via devres and allows the management code to automatically
destroy it after device removal.

dev_get_gen_pool retrieves the gen_pool for a given device, if it was
created with devm_gen_pool_create, using devres_find.

of_get_named_gen_pool retrieves the gen_pool for a given device node and
property name, where the property must contain a phandle pointing to a
platform device node. The corresponding platform device is then fed into
dev_get_gen_pool and the resulting gen_pool is returned.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
---
 include/linux/genalloc.h |   15 +++++++++
 lib/genalloc.c           |   81 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 96 insertions(+)

diff --git a/include/linux/genalloc.h b/include/linux/genalloc.h
index dd7c569..383e8f4 100644
--- a/include/linux/genalloc.h
+++ b/include/linux/genalloc.h
@@ -105,4 +105,19 @@ extern unsigned long gen_pool_first_fit(unsigned long *map, unsigned long size,
 extern unsigned long gen_pool_best_fit(unsigned long *map, unsigned long size,
 		unsigned long start, unsigned int nr, void *data);
 
+extern struct gen_pool *devm_gen_pool_create(struct device *dev,
+		int min_alloc_order, int nid);
+extern struct gen_pool *dev_get_gen_pool(struct device *dev);
+
+struct device_node;
+#ifdef CONFIG_OF
+extern struct gen_pool *of_get_named_gen_pool(struct device_node *np,
+	const char *propname, int index);
+#else
+inline struct gen_pool *of_get_named_gen_pool(struct device_node *np,
+	const char *propname, int index)
+{
+	return NULL;
+}
+#endif
 #endif /* __GENALLOC_H__ */
diff --git a/lib/genalloc.c b/lib/genalloc.c
index 5492043..b35cfa9 100644
--- a/lib/genalloc.c
+++ b/lib/genalloc.c
@@ -34,6 +34,8 @@
 #include <linux/rculist.h>
 #include <linux/interrupt.h>
 #include <linux/genalloc.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
 
 static int set_bits_ll(unsigned long *addr, unsigned long mask_to_set)
 {
@@ -480,3 +482,82 @@ unsigned long gen_pool_best_fit(unsigned long *map, unsigned long size,
 	return start_bit;
 }
 EXPORT_SYMBOL(gen_pool_best_fit);
+
+static void devm_gen_pool_release(struct device *dev, void *res)
+{
+	gen_pool_destroy(*(struct gen_pool **)res);
+}
+
+/**
+ * devm_gen_pool_create - managed gen_pool_create
+ * @dev: device that provides the gen_pool
+ * @min_alloc_order: log base 2 of number of bytes each bitmap bit represents
+ * @nid: node id of the node the pool structure should be allocated on, or -1
+ *
+ * Create a new special memory pool that can be used to manage special purpose
+ * memory not managed by the regular kmalloc/kfree interface. The pool will be
+ * automatically destroyed by the device management code.
+ */
+struct gen_pool *devm_gen_pool_create(struct device *dev, int min_alloc_order,
+		int nid)
+{
+	struct gen_pool **ptr, *pool;
+
+	ptr = devres_alloc(devm_gen_pool_release, sizeof(*ptr), GFP_KERNEL);
+
+	pool = gen_pool_create(min_alloc_order, nid);
+	if (pool) {
+		*ptr = pool;
+		devres_add(dev, ptr);
+	} else {
+		devres_free(ptr);
+	}
+
+	return pool;
+}
+
+/**
+ * dev_get_gen_pool - Obtain the gen_pool (if any) for a device
+ * @dev: device to retrieve the gen_pool from
+ * @name: Optional name for the gen_pool, usually NULL
+ *
+ * Returns the gen_pool for the device if one is present, or NULL.
+ */
+struct gen_pool *dev_get_gen_pool(struct device *dev)
+{
+	struct gen_pool **p = devres_find(dev, devm_gen_pool_release, NULL,
+					NULL);
+
+	if (!p)
+		return NULL;
+	return *p;
+}
+EXPORT_SYMBOL_GPL(dev_get_gen_pool);
+
+#ifdef CONFIG_OF
+/**
+ * of_get_named_gen_pool - find a pool by phandle property
+ * @np: device node
+ * @propname: property name containing phandle(s)
+ * @index: index into the phandle array
+ *
+ * Returns the pool that contains the chunk starting at the physical
+ * address of the device tree node pointed at by the phandle property,
+ * or NULL if not found.
+ */
+struct gen_pool *of_get_named_gen_pool(struct device_node *np,
+	const char *propname, int index)
+{
+	struct platform_device *pdev;
+	struct device_node *np_pool;
+
+	np_pool = of_parse_phandle(np, propname, index);
+	if (!np_pool)
+		return NULL;
+	pdev = of_find_device_by_node(np_pool);
+	if (!pdev)
+		return NULL;
+	return dev_get_gen_pool(&pdev->dev);
+}
+EXPORT_SYMBOL_GPL(of_get_named_gen_pool);
+#endif /* CONFIG_OF */
-- 
1.7.10.4

[PATCH v9 2/4] misc: Generic on-chip SRAM allocation driver

[Philipp Zabel]

This driver requests and remaps a memory region as configured in the
device tree. It serves memory from this region via the genalloc API.
It optionally enables the SRAM clock.

Other drivers can retrieve the genalloc pool from a phandle pointing
to this drivers' device node in the device tree.

The allocation granularity is hard-coded to 32 bytes for now,
to make the SRAM driver useful for the 6502 remoteproc driver.
There is overhead for bigger SRAMs, where only a much coarser
allocation granularity is needed: At 32 bytes minimum allocation
size, a 256 KiB SRAM needs a 1 KiB bitmap to track allocations.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
---
Changes since v8:
 - Changed device tree compatible string to "mmio-sram"
---
 Documentation/devicetree/bindings/misc/sram.txt |   16 +++
 drivers/misc/Kconfig                            |    9 ++
 drivers/misc/Makefile                           |    1 +
 drivers/misc/sram.c                             |  121 +++++++++++++++++++++++
 4 files changed, 147 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/misc/sram.txt
 create mode 100644 drivers/misc/sram.c

diff --git a/Documentation/devicetree/bindings/misc/sram.txt b/Documentation/devicetree/bindings/misc/sram.txt
new file mode 100644
index 0000000..4d0a00e
--- /dev/null
+++ b/Documentation/devicetree/bindings/misc/sram.txt
@@ -0,0 +1,16 @@
+Generic on-chip SRAM
+
+Simple IO memory regions to be managed by the genalloc API.
+
+Required properties:
+
+- compatible : mmio-sram
+
+- reg : SRAM iomem address range
+
+Example:
+
+sram: sram@5c000000 {
+	compatible = "mmio-sram";
+	reg = <0x5c000000 0x40000>; /* 256 KiB SRAM at address 0x5c000000 */
+};
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index e83fdfe..4878507 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -510,6 +510,15 @@ config LATTICE_ECP3_CONFIG
 
 	  If unsure, say N.
 
+config SRAM
+	bool "Generic on-chip SRAM driver"
+	depends on HAS_IOMEM
+	select GENERIC_ALLOCATOR
+	help
+	  This driver allows to declare a memory region to be managed
+	  by the genalloc API. It is supposed to be used for small
+	  on-chip SRAM areas found on many SoCs.
+
 source "drivers/misc/c2port/Kconfig"
 source "drivers/misc/eeprom/Kconfig"
 source "drivers/misc/cb710/Kconfig"
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 35a1463..08e2007 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -52,3 +52,4 @@ obj-$(CONFIG_INTEL_MEI)		+= mei/
 obj-$(CONFIG_MAX8997_MUIC)	+= max8997-muic.o
 obj-$(CONFIG_VMWARE_VMCI)	+= vmw_vmci/
 obj-$(CONFIG_LATTICE_ECP3_CONFIG)	+= lattice-ecp3-config.o
+obj-$(CONFIG_SRAM)		+= sram.o
diff --git a/drivers/misc/sram.c b/drivers/misc/sram.c
new file mode 100644
index 0000000..7858c62
--- /dev/null
+++ b/drivers/misc/sram.c
@@ -0,0 +1,121 @@
+/*
+ * Generic on-chip SRAM allocation driver
+ *
+ * Copyright (C) 2012 Philipp Zabel, Pengutronix
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301, USA.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/genalloc.h>
+
+#define SRAM_GRANULARITY	32
+
+struct sram_dev {
+	struct gen_pool *pool;
+	struct clk *clk;
+};
+
+static int sram_probe(struct platform_device *pdev)
+{
+	void __iomem *virt_base;
+	struct sram_dev *sram;
+	struct resource *res;
+	unsigned long size;
+	int ret;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -EINVAL;
+
+	size = resource_size(res);
+
+	virt_base = devm_request_and_ioremap(&pdev->dev, res);
+	if (!virt_base)
+		return -EADDRNOTAVAIL;
+
+	sram = devm_kzalloc(&pdev->dev, sizeof(*sram), GFP_KERNEL);
+	if (!sram)
+		return -ENOMEM;
+
+	sram->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(sram->clk))
+		sram->clk = NULL;
+	else
+		clk_prepare_enable(sram->clk);
+
+	sram->pool = devm_gen_pool_create(&pdev->dev, ilog2(SRAM_GRANULARITY), -1);
+	if (!sram->pool)
+		return -ENOMEM;
+
+	ret = gen_pool_add_virt(sram->pool, (unsigned long)virt_base,
+				res->start, size, -1);
+	if (ret < 0) {
+		gen_pool_destroy(sram->pool);
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, sram);
+
+	dev_dbg(&pdev->dev, "SRAM pool: %ld KiB @ 0x%p\n", size / 1024, virt_base);
+
+	return 0;
+}
+
+static int sram_remove(struct platform_device *pdev)
+{
+	struct sram_dev *sram = platform_get_drvdata(pdev);
+
+	if (gen_pool_avail(sram->pool) < gen_pool_size(sram->pool))
+		dev_dbg(&pdev->dev, "removed while SRAM allocated\n");
+
+	gen_pool_destroy(sram->pool);
+
+	if (sram->clk)
+		clk_disable_unprepare(sram->clk);
+
+	return 0;
+}
+
+#ifdef CONFIG_OF
+static struct of_device_id sram_dt_ids[] = {
+	{ .compatible = "mmio-sram" },
+	{}
+};
+#endif
+
+static struct platform_driver sram_driver = {
+	.driver = {
+		.name = "sram",
+		.of_match_table = of_match_ptr(sram_dt_ids),
+	},
+	.probe = sram_probe,
+	.remove = sram_remove,
+};
+
+int __init sram_init(void)
+{
+	return platform_driver_register(&sram_driver);
+}
+
+postcore_initcall(sram_init);
-- 
1.7.10.4

[PATCH v9 3/4] media: coda: use genalloc API

[Philipp Zabel]

This patch depends on "genalloc: add devres support, allow to find
a managed pool by device", which provides the of_get_named_gen_pool
and dev_get_gen_pool functions.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-By: Javier Martin <javier.martin@vista-silicon.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
---
 Documentation/devicetree/bindings/media/coda.txt |   30 +++++++++++++++
 drivers/media/platform/Kconfig                   |    1 -
 drivers/media/platform/coda.c                    |   45 +++++++++++++++-------
 include/linux/platform_data/coda.h               |   18 +++++++++
 4 files changed, 79 insertions(+), 15 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/media/coda.txt
 create mode 100644 include/linux/platform_data/coda.h

diff --git a/Documentation/devicetree/bindings/media/coda.txt b/Documentation/devicetree/bindings/media/coda.txt
new file mode 100644
index 0000000..2865d04
--- /dev/null
+++ b/Documentation/devicetree/bindings/media/coda.txt
@@ -0,0 +1,30 @@
+Chips&Media Coda multi-standard codec IP
+========================================
+
+Coda codec IPs are present in i.MX SoCs in various versions,
+called VPU (Video Processing Unit).
+
+Required properties:
+- compatible : should be "fsl,<chip>-src" for i.MX SoCs:
+  (a) "fsl,imx27-vpu" for CodaDx6 present in i.MX27
+  (b) "fsl,imx53-vpu" for CODA7541 present in i.MX53
+  (c) "fsl,imx6q-vpu" for CODA960 present in i.MX6q
+- reg: should be register base and length as documented in the
+  SoC reference manual
+- interrupts : Should contain the VPU interrupt. For CODA960,
+  a second interrupt is needed for the MJPEG unit.
+- clocks : Should contain the ahb and per clocks, in the order
+  determined by the clock-names property.
+- clock-names : Should be "ahb", "per"
+- iram : phandle pointing to the SRAM device node
+
+Example:
+
+vpu: vpu@63ff4000 {
+	compatible = "fsl,imx53-vpu";
+	reg = <0x63ff4000 0x1000>;
+	interrupts = <9>;
+	clocks = <&clks 63>, <&clks 63>;
+	clock-names = "ahb", "per";
+	iram = <&ocram>;
+};
diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
index 05d7b63..bbf83c1 100644
--- a/drivers/media/platform/Kconfig
+++ b/drivers/media/platform/Kconfig
@@ -145,7 +145,6 @@ config VIDEO_CODA
 	depends on VIDEO_DEV && VIDEO_V4L2 && ARCH_MXC
 	select VIDEOBUF2_DMA_CONTIG
 	select V4L2_MEM2MEM_DEV
-	select IRAM_ALLOC if SOC_IMX53
 	---help---
 	   Coda is a range of video codec IPs that supports
 	   H.264, MPEG-4, and other video formats.
diff --git a/drivers/media/platform/coda.c b/drivers/media/platform/coda.c
index 20827ba..b931c2a 100644
--- a/drivers/media/platform/coda.c
+++ b/drivers/media/platform/coda.c
@@ -14,6 +14,7 @@
 #include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/firmware.h>
+#include <linux/genalloc.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/irq.h>
@@ -23,7 +24,7 @@
 #include <linux/slab.h>
 #include <linux/videodev2.h>
 #include <linux/of.h>
-#include <linux/platform_data/imx-iram.h>
+#include <linux/platform_data/coda.h>
 
 #include <media/v4l2-ctrls.h>
 #include <media/v4l2-device.h>
@@ -43,6 +44,7 @@
 #define CODA7_WORK_BUF_SIZE	(512 * 1024 + CODA_FMO_BUF_SIZE * 8 * 1024)
 #define CODA_PARA_BUF_SIZE	(10 * 1024)
 #define CODA_ISRAM_SIZE	(2048 * 2)
+#define CODADX6_IRAM_SIZE	0xb000
 #define CODA7_IRAM_SIZE		0x14000 /* 81920 bytes */
 
 #define CODA_MAX_FRAMEBUFFERS	2
@@ -128,7 +130,10 @@ struct coda_dev {
 
 	struct coda_aux_buf	codebuf;
 	struct coda_aux_buf	workbuf;
+	struct gen_pool		*iram_pool;
+	long unsigned int	iram_vaddr;
 	long unsigned int	iram_paddr;
+	unsigned long		iram_size;
 
 	spinlock_t		irqlock;
 	struct mutex		dev_mutex;
@@ -1926,6 +1931,9 @@ static int coda_probe(struct platform_device *pdev)
 	const struct of_device_id *of_id =
 			of_match_device(of_match_ptr(coda_dt_ids), &pdev->dev);
 	const struct platform_device_id *pdev_id;
+	struct coda_platform_data *pdata = pdev->dev.platform_data;
+	struct device_node *np = pdev->dev.of_node;
+	struct gen_pool *pool;
 	struct coda_dev *dev;
 	struct resource *res;
 	int ret, irq;
@@ -1988,6 +1996,16 @@ static int coda_probe(struct platform_device *pdev)
 		return -ENOENT;
 	}
 
+	/* Get IRAM pool from device tree or platform data */
+	pool = of_get_named_gen_pool(np, "iram", 0);
+	if (!pool && pdata)
+		pool = dev_get_gen_pool(pdata->iram_dev);
+	if (!pool) {
+		dev_err(&pdev->dev, "iram pool not available\n");
+		return -ENOMEM;
+	}
+	dev->iram_pool = pool;
+
 	ret = v4l2_device_register(&pdev->dev, &dev->v4l2_dev);
 	if (ret)
 		return ret;
@@ -2022,18 +2040,17 @@ static int coda_probe(struct platform_device *pdev)
 		return -ENOMEM;
 	}
 
-	if (dev->devtype->product == CODA_DX6) {
-		dev->iram_paddr = 0xffff4c00;
-	} else {
-		void __iomem *iram_vaddr;
-
-		iram_vaddr = iram_alloc(CODA7_IRAM_SIZE,
-					&dev->iram_paddr);
-		if (!iram_vaddr) {
-			dev_err(&pdev->dev, "unable to alloc iram\n");
-			return -ENOMEM;
-		}
+	if (dev->devtype->product == CODA_DX6)
+		dev->iram_size = CODADX6_IRAM_SIZE;
+	else
+		dev->iram_size = CODA7_IRAM_SIZE;
+	dev->iram_vaddr = gen_pool_alloc(dev->iram_pool, dev->iram_size);
+	if (!dev->iram_vaddr) {
+		dev_err(&pdev->dev, "unable to alloc iram\n");
+		return -ENOMEM;
 	}
+	dev->iram_paddr = gen_pool_virt_to_phys(dev->iram_pool,
+						dev->iram_vaddr);
 
 	platform_set_drvdata(pdev, dev);
 
@@ -2050,8 +2067,8 @@ static int coda_remove(struct platform_device *pdev)
 	if (dev->alloc_ctx)
 		vb2_dma_contig_cleanup_ctx(dev->alloc_ctx);
 	v4l2_device_unregister(&dev->v4l2_dev);
-	if (dev->iram_paddr)
-		iram_free(dev->iram_paddr, CODA7_IRAM_SIZE);
+	if (dev->iram_vaddr)
+		gen_pool_free(dev->iram_pool, dev->iram_vaddr, dev->iram_size);
 	if (dev->codebuf.vaddr)
 		dma_free_coherent(&pdev->dev, dev->codebuf.size,
 				  &dev->codebuf.vaddr, dev->codebuf.paddr);
diff --git a/include/linux/platform_data/coda.h b/include/linux/platform_data/coda.h
new file mode 100644
index 0000000..6ad4410
--- /dev/null
+++ b/include/linux/platform_data/coda.h
@@ -0,0 +1,18 @@
+/*
+ * Copyright (C) 2013 Philipp Zabel, Pengutronix
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+#ifndef PLATFORM_CODA_H
+#define PLATFORM_CODA_H
+
+struct device;
+
+struct coda_platform_data {
+	struct device *iram_dev;
+};
+
+#endif
-- 
1.7.10.4

[PATCH v9 4/4] ARM: dts: add sram for imx53 and imx6q

[Philipp Zabel]

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
---
Changes since v8:
 - Changed device tree compatible string to "mmio-sram"
---
 arch/arm/boot/dts/imx53.dtsi |    5 +++++
 arch/arm/boot/dts/imx6q.dtsi |    6 ++++++
 2 files changed, 11 insertions(+)

diff --git a/arch/arm/boot/dts/imx53.dtsi b/arch/arm/boot/dts/imx53.dtsi
index edc3f1e..69d0680 100644
--- a/arch/arm/boot/dts/imx53.dtsi
+++ b/arch/arm/boot/dts/imx53.dtsi
@@ -664,5 +664,10 @@
 				status = "disabled";
 			};
 		};
+
+		ocram: ocram@f8000000 {
+			compatible = "fsl,imx-ocram", "mmio-sram";
+			reg = <0xf8000000 0x20000>;
+		};
 	};
 };
diff --git a/arch/arm/boot/dts/imx6q.dtsi b/arch/arm/boot/dts/imx6q.dtsi
index ff1205e..73302db 100644
--- a/arch/arm/boot/dts/imx6q.dtsi
+++ b/arch/arm/boot/dts/imx6q.dtsi
@@ -124,6 +124,12 @@
 			status = "disabled";
 		};
 
+		ocram: ocram@00900000 {
+			compatible = "fsl,imx-ocram", "mmio-sram";
+			reg = <0x00900000 0x3f000>;
+			clocks = <&clks 142>;
+		};
+
 		timer@00a00600 {
 			compatible = "arm,cortex-a9-twd-timer";
 			reg = <0x00a00600 0x20>;
-- 
1.7.10.4

Re: [PATCH v9 4/4] ARM: dts: add sram for imx53 and imx6q

[Shawn Guo]

On Wed, Feb 13, 2013 at 04:46:42PM +0100, Philipp Zabel wrote:
> Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
> Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
> Acked-by: Grant Likely <grant.likely@secretlab.ca>
> ---
> Changes since v8:
>  - Changed device tree compatible string to "mmio-sram"

Will apply it on imx tree after driver part gets applied.

Shawn

> ---
>  arch/arm/boot/dts/imx53.dtsi |    5 +++++
>  arch/arm/boot/dts/imx6q.dtsi |    6 ++++++
>  2 files changed, 11 insertions(+)
> 
> diff --git a/arch/arm/boot/dts/imx53.dtsi b/arch/arm/boot/dts/imx53.dtsi
> index edc3f1e..69d0680 100644
> --- a/arch/arm/boot/dts/imx53.dtsi
> +++ b/arch/arm/boot/dts/imx53.dtsi
> @@ -664,5 +664,10 @@
>  				status = "disabled";
>  			};
>  		};
> +
> +		ocram: ocram@f8000000 {
> +			compatible = "fsl,imx-ocram", "mmio-sram";
> +			reg = <0xf8000000 0x20000>;
> +		};
>  	};
>  };
> diff --git a/arch/arm/boot/dts/imx6q.dtsi b/arch/arm/boot/dts/imx6q.dtsi
> index ff1205e..73302db 100644
> --- a/arch/arm/boot/dts/imx6q.dtsi
> +++ b/arch/arm/boot/dts/imx6q.dtsi
> @@ -124,6 +124,12 @@
>  			status = "disabled";
>  		};
>  
> +		ocram: ocram@00900000 {
> +			compatible = "fsl,imx-ocram", "mmio-sram";
> +			reg = <0x00900000 0x3f000>;
> +			clocks = <&clks 142>;
> +		};
> +
>  		timer@00a00600 {
>  			compatible = "arm,cortex-a9-twd-timer";
>  			reg = <0x00a00600 0x20>;
> -- 
> 1.7.10.4
> 

Re: [PATCH v9 0/4] Add generic driver for on-chip SRAM

[Dinh Nguyen]

Hi Philipp,

On Wed, 2013-02-13 at 16:46 +0100, Philipp Zabel wrote:
> These patches add support to configure on-chip SRAM via device-tree
> node or platform data and to obtain the resulting genalloc pool from
> the struct device pointer or a phandle pointing at the device tree node.
> This allows drivers to allocate SRAM with the genalloc API without
> hard-coding the genalloc pool pointer.
> 
> The on-chip SRAM on i.MX53 and i.MX6q can be registered via device tree
> and changed to use the simple generic SRAM driver:
> 
>                 ocram: ocram@00900000 {
>                         compatible = "fsl,imx-ocram", "mmio-sram";
>                         reg = <0x00900000 0x3f000>;
>                 };
> 
> A driver that needs to allocate SRAM buffers, like the video processing
> unit on i.MX53, can retrieve the genalloc pool from a phandle in the
> device tree using of_get_named_gen_pool(node, "iram", 0) from patch 1:
> 
>                 vpu@63ff4000 {
>                         /* ... */
>                         iram = <&ocram>;
>                 };
> 
> Changes since v8:
>  - The sram driver now matches against the "mmio-sram" compatible string.
>  - Removed a whitespace error in the device tree binding documentation.
> 
> regards
> Philipp
> 
> ---
>  Documentation/devicetree/bindings/media/coda.txt |   30 ++++++
>  Documentation/devicetree/bindings/misc/sram.txt  |   16 +++
>  arch/arm/boot/dts/imx53.dtsi                     |    5 +
>  arch/arm/boot/dts/imx6q.dtsi                     |    6 ++
>  drivers/media/platform/Kconfig                   |    1 -
>  drivers/media/platform/coda.c                    |   45 +++++---
>  drivers/misc/Kconfig                             |    9 ++
>  drivers/misc/Makefile                            |    1 +
>  drivers/misc/sram.c                              |  121 ++++++++++++++++++++++
>  include/linux/genalloc.h                         |   15 +++
>  include/linux/platform_data/coda.h               |   18 ++++
>  lib/genalloc.c                                   |   81 +++++++++++++++
>  12 files changed, 333 insertions(+), 15 deletions(-)
> 

Sorry the late comment, with this patch I think you can probably remove:

linux/platform_data/imx-iram.himx-iram.h
mach-imx/iram_alloc.c


I don't see any usage of iram_init except for coda.

Dinh


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