These patches add support to configure on-chip SRAM via device-tree
node and to obtain the resulting genalloc pool from a phandle pointing
at the node.
This allows drivers to allocate SRAM with the genalloc API without
hard-coding the genalloc pool address.
The on-chip SRAM on i.MX53 and i.MX6q is registered via device tree and
changed to use the simple generic SRAM driver:
ocram: ocram@00900000 {
compatible = "fsl,imx-ocram", "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 5:
vpu@63ff4000 {
/* ... */
iram = <&ocram>;
};
Changes since v1:
- Added a generic SRAM driver in drivers/misc that does nothing but
request/ioremap its given memory region and serve it via the genalloc
API.
- Renamed the i.MX device tree nodes from "iram" to "ocram".
regards
Philipp
---
arch/arm/boot/dts/imx53.dtsi | 5 ++
arch/arm/boot/dts/imx6q.dtsi | 5 ++
arch/arm/plat-mxc/Kconfig | 4 --
arch/arm/plat-mxc/Makefile | 1 -
arch/arm/plat-mxc/include/mach/iram.h | 41 -------------
arch/arm/plat-mxc/iram_alloc.c | 73 -----------------------
drivers/misc/Kconfig | 8 +++
drivers/misc/Makefile | 1 +
drivers/misc/sram.c | 105 +++++++++++++++++++++++++++++++++
include/linux/genalloc.h | 14 +++++
lib/genalloc.c | 77 ++++++++++++++++++++++++
11 files changed, 215 insertions(+), 119 deletions(-)
Signed-off-by: Philipp Zabel <[email protected]>
---
arch/arm/boot/dts/imx53.dtsi | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/arm/boot/dts/imx53.dtsi b/arch/arm/boot/dts/imx53.dtsi
index 5da342a..2767a92 100644
--- a/arch/arm/boot/dts/imx53.dtsi
+++ b/arch/arm/boot/dts/imx53.dtsi
@@ -338,8 +338,8 @@
};
};
- ocram@f8000000 {
- compatible = "fsl,imx-ocram";
+ ocram: ocram@f8000000 {
+ compatible = "fsl,imx-ocram", "sram";
reg = <0xf8000000 0x20000>;
};
};
--
1.7.10.4
Signed-off-by: Philipp Zabel <[email protected]>
---
arch/arm/boot/dts/imx6q.dtsi | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/arm/boot/dts/imx6q.dtsi b/arch/arm/boot/dts/imx6q.dtsi
index 9cb0b50..1e463c4 100644
--- a/arch/arm/boot/dts/imx6q.dtsi
+++ b/arch/arm/boot/dts/imx6q.dtsi
@@ -111,8 +111,8 @@
status = "disabled";
};
- ocram@00900000 {
- compatible = "fsl,imx-ocram";
+ ocram: ocram@00900000 {
+ compatible = "fsl,imx-ocram", "sram";
reg = <0x00900000 0x3f000>;
};
--
1.7.10.4
Signed-off-by: Philipp Zabel <[email protected]>
---
arch/arm/plat-mxc/include/mach/iram.h | 6 -----
arch/arm/plat-mxc/iram_alloc.c | 44 ++++++++++++++++++++++++++++++---
2 files changed, 41 insertions(+), 9 deletions(-)
diff --git a/arch/arm/plat-mxc/include/mach/iram.h b/arch/arm/plat-mxc/include/mach/iram.h
index 022690c..d5c863f 100644
--- a/arch/arm/plat-mxc/include/mach/iram.h
+++ b/arch/arm/plat-mxc/include/mach/iram.h
@@ -20,17 +20,11 @@
#ifdef CONFIG_IRAM_ALLOC
-int __init iram_init(unsigned long base, unsigned long size);
void __iomem *iram_alloc(unsigned int size, unsigned long *dma_addr);
void iram_free(unsigned long dma_addr, unsigned int size);
#else
-static inline int __init iram_init(unsigned long base, unsigned long size)
-{
- return -ENOMEM;
-}
-
static inline void __iomem *iram_alloc(unsigned int size, unsigned long *dma_addr)
{
return NULL;
diff --git a/arch/arm/plat-mxc/iram_alloc.c b/arch/arm/plat-mxc/iram_alloc.c
index 074c386..673deb4 100644
--- a/arch/arm/plat-mxc/iram_alloc.c
+++ b/arch/arm/plat-mxc/iram_alloc.c
@@ -22,6 +22,8 @@
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/genalloc.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
#include <mach/iram.h>
static unsigned long iram_phys_base;
@@ -55,15 +57,26 @@ void iram_free(unsigned long addr, unsigned int size)
}
EXPORT_SYMBOL(iram_free);
-int __init iram_init(unsigned long base, unsigned long size)
+static int __devinit iram_probe(struct platform_device *pdev)
{
- iram_phys_base = base;
+ struct resource *res;
+ unsigned long size;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -EINVAL;
+
+ if (iram_phys_base)
+ return -EBUSY;
+
+ iram_phys_base = res->start;
+ size = resource_size(res);
iram_pool = gen_pool_create(PAGE_SHIFT, -1);
if (!iram_pool)
return -ENOMEM;
- gen_pool_add(iram_pool, base, size, -1);
+ gen_pool_add(iram_pool, res->start, size, -1);
iram_virt_base = ioremap(iram_phys_base, size);
if (!iram_virt_base)
return -EIO;
@@ -71,3 +84,28 @@ int __init iram_init(unsigned long base, unsigned long size)
pr_debug("i.MX IRAM pool: %ld KB@0x%p\n", size / 1024, iram_virt_base);
return 0;
}
+
+static int __devexit iram_remove(struct platform_device *pdev)
+{
+ gen_pool_destroy(iram_pool);
+ iram_pool = NULL;
+ return 0;
+}
+
+#ifdef CONFIG_OF
+static struct of_device_id iram_dt_ids[] = {
+ { .compatible = "fsl,imx-iram" },
+ { /* sentinel */ }
+};
+#endif
+
+static struct platform_driver iram_driver = {
+ .driver = {
+ .name = "imx-iram",
+ .of_match_table = of_match_ptr(iram_dt_ids),
+ },
+ .probe = iram_probe,
+ .remove = __devexit_p(iram_remove),
+};
+
+module_platform_driver(iram_driver);
--
1.7.10.4
This driver requests and remaps a memory region as configured in the
device tree. It serves memory from this region via the genalloc API.
Other drivers can retrieve the genalloc pool from a phandle pointing
to this drivers' device node in the device tree.
Signed-off-by: Philipp Zabel <[email protected]>
---
drivers/misc/Kconfig | 8 ++++
drivers/misc/Makefile | 1 +
drivers/misc/sram.c | 105 +++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 114 insertions(+)
create mode 100644 drivers/misc/sram.c
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 98a442d..8a55284 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -509,6 +509,14 @@ config USB_SWITCH_FSA9480
stereo and mono audio, video, microphone and UART data to use
a common connector port.
+config SRAM
+ bool "Generic on-chip SRAM driver\n"
+ 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 ARM 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 b88df7a..ccc759a 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -50,3 +50,4 @@ obj-y += carma/
obj-$(CONFIG_USB_SWITCH_FSA9480) += fsa9480.o
obj-$(CONFIG_ALTERA_STAPL) +=altera-stapl/
obj-$(CONFIG_INTEL_MEI) += mei/
+obj-$(CONFIG_SRAM) += sram.o
diff --git a/drivers/misc/sram.c b/drivers/misc/sram.c
new file mode 100644
index 0000000..c5cf67e
--- /dev/null
+++ b/drivers/misc/sram.c
@@ -0,0 +1,105 @@
+/*
+ * 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/module.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+#include <linux/genalloc.h>
+
+struct sram_dev {
+ struct gen_pool *pool;
+};
+
+static int __devinit 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 -ENOMEM;
+
+ sram = devm_kzalloc(&pdev->dev, sizeof(*sram), GFP_KERNEL);
+ if (!sram)
+ return -ENOMEM;
+
+ sram->pool = gen_pool_create(PAGE_SHIFT, -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 __devexit 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);
+
+ return 0;
+}
+
+#ifdef CONFIG_OF
+static struct of_device_id sram_dt_ids[] = {
+ { .compatible = "sram" },
+ { /* sentinel */ }
+};
+#endif
+
+static struct platform_driver sram_driver = {
+ .driver = {
+ .name = "sram",
+ .of_match_table = of_match_ptr(sram_dt_ids),
+ },
+ .probe = sram_probe,
+ .remove = __devexit_p(sram_remove),
+};
+
+module_platform_driver(sram_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Philipp Zabel, Pengutronix");
+MODULE_DESCRIPTION("Generic SRAM allocator driver");
--
1.7.10.4
A generic on-chip SRAM allocator driver can be used instead.
Users of the iram_alloc/free API should convert to the genalloc API:
- virt = iram_alloc(SIZE, &phys);
+ gen_pool_alloc(iram_pool, SIZE);
+ phys = gen_pool_virt_to_phys(iram_pool, virt);
/* ... */
- iram_free(virt, SIZE);
+ gen_pool_free(iram_pool, virt, SIZE);
Signed-off-by: Philipp Zabel <[email protected]>
---
arch/arm/plat-mxc/Kconfig | 4 --
arch/arm/plat-mxc/Makefile | 1 -
arch/arm/plat-mxc/include/mach/iram.h | 35 ----------
arch/arm/plat-mxc/iram_alloc.c | 116 ---------------------------------
4 files changed, 156 deletions(-)
delete mode 100644 arch/arm/plat-mxc/include/mach/iram.h
delete mode 100644 arch/arm/plat-mxc/iram_alloc.c
diff --git a/arch/arm/plat-mxc/Kconfig b/arch/arm/plat-mxc/Kconfig
index baf9064..8e63f10 100644
--- a/arch/arm/plat-mxc/Kconfig
+++ b/arch/arm/plat-mxc/Kconfig
@@ -82,8 +82,4 @@ config IMX_HAVE_IOMUX_V1
config ARCH_MXC_IOMUX_V3
bool
-config IRAM_ALLOC
- bool
- select GENERIC_ALLOCATOR
-
endif
diff --git a/arch/arm/plat-mxc/Makefile b/arch/arm/plat-mxc/Makefile
index 6ac7200..bdf370f 100644
--- a/arch/arm/plat-mxc/Makefile
+++ b/arch/arm/plat-mxc/Makefile
@@ -10,7 +10,6 @@ obj-$(CONFIG_MXC_AVIC) += avic.o
obj-$(CONFIG_IMX_HAVE_IOMUX_V1) += iomux-v1.o
obj-$(CONFIG_ARCH_MXC_IOMUX_V3) += iomux-v3.o
-obj-$(CONFIG_IRAM_ALLOC) += iram_alloc.o
obj-$(CONFIG_MXC_ULPI) += ulpi.o
obj-$(CONFIG_MXC_USE_EPIT) += epit.o
obj-$(CONFIG_MXC_DEBUG_BOARD) += 3ds_debugboard.o
diff --git a/arch/arm/plat-mxc/include/mach/iram.h b/arch/arm/plat-mxc/include/mach/iram.h
deleted file mode 100644
index d5c863f..0000000
--- a/arch/arm/plat-mxc/include/mach/iram.h
+++ /dev/null
@@ -1,35 +0,0 @@
-/*
- * Copyright (C) 2010 Freescale Semiconductor, Inc. All Rights Reserved.
- *
- * 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/errno.h>
-
-#ifdef CONFIG_IRAM_ALLOC
-
-void __iomem *iram_alloc(unsigned int size, unsigned long *dma_addr);
-void iram_free(unsigned long dma_addr, unsigned int size);
-
-#else
-
-static inline void __iomem *iram_alloc(unsigned int size, unsigned long *dma_addr)
-{
- return NULL;
-}
-
-static inline void iram_free(unsigned long base, unsigned long size) {}
-
-#endif
diff --git a/arch/arm/plat-mxc/iram_alloc.c b/arch/arm/plat-mxc/iram_alloc.c
deleted file mode 100644
index 343e96d..0000000
--- a/arch/arm/plat-mxc/iram_alloc.c
+++ /dev/null
@@ -1,116 +0,0 @@
-/*
- * Copyright (C) 2010 Freescale Semiconductor, Inc. All Rights Reserved.
- *
- * 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/io.h>
-#include <linux/module.h>
-#include <linux/spinlock.h>
-#include <linux/genalloc.h>
-#include <linux/of.h>
-#include <linux/platform_device.h>
-#include <mach/iram.h>
-
-static struct gen_pool *iram_pool;
-
-void __iomem *iram_alloc(unsigned int size, unsigned long *dma_addr)
-{
- unsigned long virt;
-
- if (!iram_pool)
- return NULL;
-
- virt = gen_pool_alloc(iram_pool, size);
- pr_debug("iram alloc - %dB@0x%lX\n", size, *dma_addr);
- if (!virt)
- return NULL;
-
- *dma_addr = gen_pool_virt_to_phys(iram_pool, virt);
- return (void __iomem *)virt;
-}
-EXPORT_SYMBOL(iram_alloc);
-
-void iram_free(unsigned long addr, unsigned int size)
-{
- if (!iram_pool)
- return;
-
- gen_pool_free(iram_pool, addr, size);
-}
-EXPORT_SYMBOL(iram_free);
-
-static int __devinit iram_probe(struct platform_device *pdev)
-{
- void __iomem *virt_base;
- struct resource *res;
- unsigned long size;
- int ret;
-
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (!res)
- return -EINVAL;
-
- if (iram_pool)
- return -EBUSY;
-
- size = resource_size(res);
-
- virt_base = devm_ioremap(&pdev->dev, res->start, size);
- if (!virt_base)
- return -ENOMEM;
-
- iram_pool = gen_pool_create(PAGE_SHIFT, -1);
- if (!iram_pool)
- return -ENOMEM;
-
- ret = gen_pool_add_virt(iram_pool, (unsigned long)virt_base,
- res->start, size, -1);
- if (ret < 0) {
- gen_pool_destroy(iram_pool);
- iram_pool = NULL;
- return ret;
- }
-
- pr_debug("i.MX IRAM pool: %ld KB@0x%p\n", size / 1024, virt_base);
- return 0;
-}
-
-static int __devexit iram_remove(struct platform_device *pdev)
-{
- gen_pool_destroy(iram_pool);
- iram_pool = NULL;
- return 0;
-}
-
-#ifdef CONFIG_OF
-static struct of_device_id iram_dt_ids[] = {
- { .compatible = "fsl,imx-iram" },
- { /* sentinel */ }
-};
-#endif
-
-static struct platform_driver iram_driver = {
- .driver = {
- .name = "imx-iram",
- .of_match_table = of_match_ptr(iram_dt_ids),
- },
- .probe = iram_probe,
- .remove = __devexit_p(iram_remove),
-};
-
-module_platform_driver(iram_driver);
--
1.7.10.4
This patch keeps all created pools in a global list and adds two
functions that allow to retrieve the gen_pool pointer from a known
physical address and from a device tree node.
Signed-off-by: Philipp Zabel <[email protected]>
---
include/linux/genalloc.h | 14 +++++++++
lib/genalloc.c | 77 ++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 91 insertions(+)
diff --git a/include/linux/genalloc.h b/include/linux/genalloc.h
index 5e98eeb..46ff435 100644
--- a/include/linux/genalloc.h
+++ b/include/linux/genalloc.h
@@ -33,6 +33,7 @@
* General purpose special memory pool descriptor.
*/
struct gen_pool {
+ struct list_head next_pool; /* pool in global list */
spinlock_t lock;
struct list_head chunks; /* list of chunks in this pool */
int min_alloc_order; /* minimum allocation order */
@@ -78,4 +79,17 @@ extern void gen_pool_for_each_chunk(struct gen_pool *,
void (*)(struct gen_pool *, struct gen_pool_chunk *, void *), void *);
extern size_t gen_pool_avail(struct gen_pool *);
extern size_t gen_pool_size(struct gen_pool *);
+extern struct gen_pool *gen_pool_find_by_phys(phys_addr_t phys);
+
+#ifdef CONFIG_OF
+struct device_node;
+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 6bc04aa..df2d8f9 100644
--- a/lib/genalloc.c
+++ b/lib/genalloc.c
@@ -34,6 +34,11 @@
#include <linux/rculist.h>
#include <linux/interrupt.h>
#include <linux/genalloc.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+
+static LIST_HEAD(pools);
+static DEFINE_SPINLOCK(list_lock);
static int set_bits_ll(unsigned long *addr, unsigned long mask_to_set)
{
@@ -152,6 +157,9 @@ struct gen_pool *gen_pool_create(int min_alloc_order, int nid)
spin_lock_init(&pool->lock);
INIT_LIST_HEAD(&pool->chunks);
pool->min_alloc_order = min_alloc_order;
+ spin_lock(&list_lock);
+ list_add_rcu(&pool->next_pool, &pools);
+ spin_unlock(&list_lock);
}
return pool;
}
@@ -234,6 +242,9 @@ void gen_pool_destroy(struct gen_pool *pool)
int order = pool->min_alloc_order;
int bit, end_bit;
+ spin_lock(&list_lock);
+ list_del_rcu(&pool->next_pool);
+ spin_unlock(&list_lock);
list_for_each_safe(_chunk, _next_chunk, &pool->chunks) {
chunk = list_entry(_chunk, struct gen_pool_chunk, next_chunk);
list_del(&chunk->next_chunk);
@@ -400,3 +411,69 @@ size_t gen_pool_size(struct gen_pool *pool)
return size;
}
EXPORT_SYMBOL_GPL(gen_pool_size);
+
+/**
+ * gen_pool_find_by_phys - find a pool by physical start address
+ * @phys: physical address as added with gen_pool_add_virt
+ *
+ * Returns the pool that contains the chunk starting at phys,
+ * or NULL if not found.
+ */
+struct gen_pool *gen_pool_find_by_phys(phys_addr_t phys)
+{
+ struct gen_pool *pool, *found = NULL;
+ struct gen_pool_chunk *chunk;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(pool, &pools, next_pool) {
+ list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk) {
+ if (phys == chunk->phys_addr) {
+ found = pool;
+ break;
+ }
+ }
+ }
+ rcu_read_unlock();
+
+ return found;
+}
+EXPORT_SYMBOL_GPL(gen_pool_find_by_phys);
+
+#ifdef CONFIG_OF
+/**
+ * of_get_named_gen_pool - find a pool by the physical address in
+ * @np: device node
+ *
+ * Returns the pool that contains the chunk starting at the physical
+ * address of the np device node, or NULL if not found.
+ */
+struct gen_pool *of_get_named_gen_pool(struct device_node *np,
+ const char *propname, int index)
+{
+ struct property *prop;
+ const __be32 *list;
+ int size;
+ phandle phandle;
+ struct device_node *np_pool;
+ const u32 *reg;
+ u64 addr;
+
+ prop = of_find_property(np, propname, &size);
+ if (!prop)
+ return NULL;
+ list = prop->value;
+ size /= sizeof(*list);
+ phandle = be32_to_cpup(list);
+ np_pool = of_find_node_by_phandle(phandle);
+ if (!np_pool)
+ return NULL;
+ reg = of_get_property(np_pool, "reg", NULL);
+ if (!reg)
+ return NULL;
+ addr = of_translate_address(np_pool, reg);
+ if (addr == OF_BAD_ADDR)
+ return NULL;
+ return gen_pool_find_by_phys((phys_addr_t) addr);
+}
+EXPORT_SYMBOL_GPL(of_get_named_gen_pool);
+#endif /* CONFIG_OF */
--
1.7.10.4
This improves the symmetry of iram_alloc and iram_free in that
iram_free has to be called with the virtual address now.
Also, gen_pool_virt_to_phys is now functional.
Signed-off-by: Philipp Zabel <[email protected]>
---
arch/arm/plat-mxc/iram_alloc.c | 39 ++++++++++++++++++++++-----------------
1 file changed, 22 insertions(+), 17 deletions(-)
diff --git a/arch/arm/plat-mxc/iram_alloc.c b/arch/arm/plat-mxc/iram_alloc.c
index 673deb4..343e96d 100644
--- a/arch/arm/plat-mxc/iram_alloc.c
+++ b/arch/arm/plat-mxc/iram_alloc.c
@@ -26,25 +26,22 @@
#include <linux/platform_device.h>
#include <mach/iram.h>
-static unsigned long iram_phys_base;
-static void __iomem *iram_virt_base;
static struct gen_pool *iram_pool;
-static inline void __iomem *iram_phys_to_virt(unsigned long p)
-{
- return iram_virt_base + (p - iram_phys_base);
-}
-
void __iomem *iram_alloc(unsigned int size, unsigned long *dma_addr)
{
+ unsigned long virt;
+
if (!iram_pool)
return NULL;
- *dma_addr = gen_pool_alloc(iram_pool, size);
+ virt = gen_pool_alloc(iram_pool, size);
pr_debug("iram alloc - %dB@0x%lX\n", size, *dma_addr);
- if (!*dma_addr)
+ if (!virt)
return NULL;
- return iram_phys_to_virt(*dma_addr);
+
+ *dma_addr = gen_pool_virt_to_phys(iram_pool, virt);
+ return (void __iomem *)virt;
}
EXPORT_SYMBOL(iram_alloc);
@@ -59,29 +56,37 @@ EXPORT_SYMBOL(iram_free);
static int __devinit iram_probe(struct platform_device *pdev)
{
+ void __iomem *virt_base;
struct resource *res;
unsigned long size;
+ int ret;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
return -EINVAL;
- if (iram_phys_base)
+ if (iram_pool)
return -EBUSY;
- iram_phys_base = res->start;
size = resource_size(res);
+ virt_base = devm_ioremap(&pdev->dev, res->start, size);
+ if (!virt_base)
+ return -ENOMEM;
+
iram_pool = gen_pool_create(PAGE_SHIFT, -1);
if (!iram_pool)
return -ENOMEM;
- gen_pool_add(iram_pool, res->start, size, -1);
- iram_virt_base = ioremap(iram_phys_base, size);
- if (!iram_virt_base)
- return -EIO;
+ ret = gen_pool_add_virt(iram_pool, (unsigned long)virt_base,
+ res->start, size, -1);
+ if (ret < 0) {
+ gen_pool_destroy(iram_pool);
+ iram_pool = NULL;
+ return ret;
+ }
- pr_debug("i.MX IRAM pool: %ld KB@0x%p\n", size / 1024, iram_virt_base);
+ pr_debug("i.MX IRAM pool: %ld KB@0x%p\n", size / 1024, virt_base);
return 0;
}
--
1.7.10.4
Signed-off-by: Philipp Zabel <[email protected]>
---
Changes since v1:
- Renamed "iram" to "ocram" as it appears in the processor
reference manuals.
---
arch/arm/boot/dts/imx6q.dtsi | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/arch/arm/boot/dts/imx6q.dtsi b/arch/arm/boot/dts/imx6q.dtsi
index fd57079..9cb0b50 100644
--- a/arch/arm/boot/dts/imx6q.dtsi
+++ b/arch/arm/boot/dts/imx6q.dtsi
@@ -111,6 +111,11 @@
status = "disabled";
};
+ ocram@00900000 {
+ compatible = "fsl,imx-ocram";
+ reg = <0x00900000 0x3f000>;
+ };
+
timer@00a00600 {
compatible = "arm,cortex-a9-twd-timer";
reg = <0x00a00600 0x20>;
--
1.7.10.4
Signed-off-by: Philipp Zabel <[email protected]>
---
- Renamed "iram" to "ocram" as it appears in the processor
reference manuals.
---
arch/arm/boot/dts/imx53.dtsi | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/arch/arm/boot/dts/imx53.dtsi b/arch/arm/boot/dts/imx53.dtsi
index cd37165..5da342a 100644
--- a/arch/arm/boot/dts/imx53.dtsi
+++ b/arch/arm/boot/dts/imx53.dtsi
@@ -337,5 +337,10 @@
status = "disabled";
};
};
+
+ ocram@f8000000 {
+ compatible = "fsl,imx-ocram";
+ reg = <0xf8000000 0x20000>;
+ };
};
};
--
1.7.10.4
On Fri, 2012-08-31 at 11:27 +0200, Philipp Zabel wrote:
> This driver requests and remaps a memory region as configured in the
> device tree. It serves memory from this region via the genalloc API.
>
> Other drivers can retrieve the genalloc pool from a phandle pointing
> to this drivers' device node in the device tree.
>
> Signed-off-by: Philipp Zabel <[email protected]>
> ---
> drivers/misc/Kconfig | 8 ++++
> drivers/misc/Makefile | 1 +
> drivers/misc/sram.c | 105 +++++++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 114 insertions(+)
> create mode 100644 drivers/misc/sram.c
We now have drivers/memory, which seems to be a good place for this.
Regards,
Jan
--
Pengutronix e.K. | |
Industrial Linux Solutions | http://www.pengutronix.de/ |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
On Fri, Aug 31, 2012 at 2:37 AM, Jan L?bbe <[email protected]> wrote:
>
> On Fri, 2012-08-31 at 11:27 +0200, Philipp Zabel wrote:
> > This driver requests and remaps a memory region as configured in the
> > device tree. It serves memory from this region via the genalloc API.
> >
> > Other drivers can retrieve the genalloc pool from a phandle pointing
> > to this drivers' device node in the device tree.
> >
> > Signed-off-by: Philipp Zabel <[email protected]>
> > ---
> > drivers/misc/Kconfig | 8 ++++
> > drivers/misc/Makefile | 1 +
> > drivers/misc/sram.c | 105
> > +++++++++++++++++++++++++++++++++++++++++++++++++
> > 3 files changed, 114 insertions(+)
> > create mode 100644 drivers/misc/sram.c
>
> We now have drivers/memory, which seems to be a good place for this.
>
drivers/memory is created for Memory controller device drivers. SRAM is
just pool of memory and should belong to some other place.
Regards
Santosh