Add support for handling 'shared-dma-pool' reserved-memory nodes. Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: Laura Abbott <lauraa@xxxxxxxxxxxxxx> Cc: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> Signed-off-by: Josh Cartwright <joshc@xxxxxxxxxxxxxx> --- 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.szyprowski@xxxxxxxxxxx> + * Author: Josh Cartwright <joshc@xxxxxxxxxxxxxx> + * + * 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 devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
