Add support for handling 'shared-dma-pool' reserved-memory nodes.
Cc: Benjamin Herrenschmidt <b...@kernel.crashing.org>
Cc: Laura Abbott <lau...@codeaurora.org>
Cc: Marek Szyprowski <m.szyprow...@samsung.com>
Signed-off-by: Josh Cartwright <jo...@codeaurora.org>
---
drivers/of/Kconfig | 7 ++
drivers/of/Makefile | 1 +
drivers/of/of_reserved_mem_dma.c | 178 +++++++++++++++++++++++++++++++++++++++
3 files changed, 186 insertions(+)
create mode 100644 drivers/of/of_reserved_mem_dma.c
diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
index aba13df..ca58fb3e 100644
--- a/drivers/of/Kconfig
+++ b/drivers/of/Kconfig
@@ -81,4 +81,11 @@ config OF_RESERVED_MEM
help
Helpers to allow for reservation of memory regions
+config OF_RESERVED_MEM_DMA
+ depends on OF_RESERVED_MEM
+ depends on DMA_CMA || HAVE_GENERIC_DMA_COHERENT
+ def_bool y
+ help
+ Helpers for reserving memory regions for DMA use
+
endmenu # OF
diff --git a/drivers/of/Makefile b/drivers/of/Makefile
index ed9660a..6142227 100644
--- a/drivers/of/Makefile
+++ b/drivers/of/Makefile
@@ -10,3 +10,4 @@ obj-$(CONFIG_OF_PCI) += of_pci.o
obj-$(CONFIG_OF_PCI_IRQ) += of_pci_irq.o
obj-$(CONFIG_OF_MTD) += of_mtd.o
obj-$(CONFIG_OF_RESERVED_MEM) += of_reserved_mem.o
+obj-$(CONFIG_OF_RESERVED_MEM_DMA) += of_reserved_mem_dma.o
diff --git a/drivers/of/of_reserved_mem_dma.c b/drivers/of/of_reserved_mem_dma.c
new file mode 100644
index 0000000..e24f02d
--- /dev/null
+++ b/drivers/of/of_reserved_mem_dma.c
@@ -0,0 +1,178 @@
+/*
+ * Device tree based initialization code for DMA reserved regions.
+ *
+ * Copyright (c) 2013, The Linux Foundation. All Rights Reserved.
+ * Copyright (c) 2013 Samsung Electronics Co., Ltd.
+ * http://www.samsung.com
+ * Author: Marek Szyprowski <m.szyprow...@samsung.com>
+ * Author: Josh Cartwright <jo...@codeaurora.org>
+ *
+ * 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 optional) any later version of the license.
+ */
+#include <linux/memblock.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/of_platform.h>
+#include <linux/mm.h>
+#include <linux/sizes.h>
+#include <linux/mm_types.h>
+#include <linux/dma-contiguous.h>
+#include <linux/dma-mapping.h>
+#include <linux/of_reserved_mem.h>
+
+static void rmem_dma_device_init(struct reserved_mem *rmem,
+ struct platform_device *pdev,
+ struct of_phandle_args *args)
+{
+ dma_declare_coherent_memory(&pdev->dev, rmem->base, rmem->base,
+ rmem->size, DMA_MEMORY_MAP | DMA_MEMORY_EXCLUSIVE);
+}
+
+static void rmem_dma_device_release(struct reserved_mem *rmem,
+ struct platform_device *pdev)
+{
+ dma_release_declared_memory(&pdev->dev);
+}
+
+static const struct reserved_mem_ops rmem_dma_ops = {
+ .device_init = rmem_dma_device_init,
+ .device_release = rmem_dma_device_release,
+};
+
+static int __init rmem_dma_get_reg(unsigned long node, const char *uname,
+ phys_addr_t *base, phys_addr_t *size)
+{
+ unsigned long len;
+ __be32 *prop;
+
+ prop = of_get_flat_dt_prop(node, "reg", &len);
+ if (!prop)
+ return -EINVAL;
+
+ if (len < (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32)) {
+ pr_err("Malformed 'shared-dma-pool' reserved-mem node '%s'.\n",
+ uname);
+ return -EINVAL;
+ }
+
+ *base = dt_mem_next_cell(dt_root_addr_cells, &prop);
+ *size = dt_mem_next_cell(dt_root_size_cells, &prop);
+ return 0;
+}
+
+static int __init rmem_dma_get_size(unsigned long node, const char *uname,
+ phys_addr_t *size)
+{
+ unsigned long len;
+ __be32 *prop;
+
+ prop = of_get_flat_dt_prop(node, "size", &len);
+ if (!prop)
+ return -EINVAL;
+
+ if (len < dt_root_size_cells * sizeof(__be32)) {
+ pr_err("Malformed 'shared-dma-pool' reserved-mem node '%s'.\n",
+ uname);
+ return -EINVAL;
+ }
+
+ *size = dt_mem_next_cell(dt_root_size_cells, &prop);
+ return 0;
+}
+
+static void rmem_cma_device_init(struct reserved_mem *rmem,
+ struct platform_device *pdev,
+ struct of_phandle_args *args)
+{
+ dev_set_cma_area(&pdev->dev, rmem->cma);
+}
+
+static const struct reserved_mem_ops rmem_cma_ops = {
+ .device_init = rmem_cma_device_init,
+};
+
+static int __init rmem_cma_reserve_area(struct reserved_mem *rmem,
+ unsigned long node, const char *uname)
+{
+ int err;
+
+ err = dma_contiguous_reserve_area(rmem->size, rmem->base, 0,
+ &rmem->cma);
+ if (err) {
+ pr_err("Unable to setup CMA reserved-mem region for '%s'.\n",
+ uname);
+ return err;
+ }
+
+ if (of_get_flat_dt_prop(node, "linux,cma-default", NULL))
+ dma_contiguous_set_default(rmem->cma);
+
+ rmem->ops = &rmem_cma_ops;
+ return 0;
+}
+
+static int __init rmem_cma_setup(struct reserved_mem *rmem,
+ unsigned long node,
+ const char *uname)
+{
+ int err;
+
+ err = rmem_dma_get_reg(node, uname, &rmem->base, &rmem->size);
+ if (!err)
+ goto out_done;
+
+ rmem->base = 0;
+ err = rmem_dma_get_size(node, uname, &rmem->size);
+ if (err)
+ goto out_err;
+
+out_done:
+ return rmem_cma_reserve_area(rmem, node, uname);
+
+out_err:
+ pr_err("Malformed 'shared-dma-pool' node '%s'.\n", uname);
+ return err;
+}
+
+static int __init rmem_dma_excl_setup(struct reserved_mem *rmem,
+ unsigned long node,
+ const char *uname)
+{
+ int err;
+
+ err = rmem_dma_get_reg(node, uname, &rmem->base, &rmem->size);
+ if (!err)
+ goto out_done;
+
+ err = rmem_dma_get_size(node, uname, &rmem->size);
+ if (err)
+ goto out_err;
+
+ rmem->base = memblock_alloc_base(rmem->size, PAGE_SIZE,
+ MEMBLOCK_ALLOC_ANYWHERE);
+ memblock_free(rmem->base, rmem->size);
+
+out_done:
+ rmem->ops = &rmem_dma_ops;
+ return memblock_remove(rmem->base, rmem->size);
+
+out_err:
+ pr_err("Unable to setup reserved-mem region '%s' for DMA.\n", uname);
+ return err;
+}
+
+static int __init rmem_dma_setup(struct reserved_mem *rmem,
+ unsigned long node,
+ const char *uname)
+{
+ if (IS_ENABLED(CONFIG_DMA_CMA) &&
+ of_get_flat_dt_prop(node, "reusable", NULL))
+ return rmem_cma_setup(rmem, node, uname);
+
+ return rmem_dma_excl_setup(rmem, node, uname);
+}
+RESERVEDMEM_OF_DECLARE(dma, "shared-dma-pool", rmem_dma_setup);
--
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
hosted by The Linux Foundation
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
