Commit d552ddea authored by Jim Quinlan's avatar Jim Quinlan Committed by Thomas Bogendoerfer
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MIPS: bmips: Remove obsolete DMA mapping support 



The code in 'arch/mips/bmips/dma.c' performed DMA mapping for inbound
regions.  This mapping was and is required for the Broadcom STB PCIe
controller HW.  This code is removed as the current 'struct device' has a
@dma_range_map field which performs the same functionality by processing
the "dma-ranges" DT property.

Subsequently, ARCH_HAS_PHYS_TO_DMA is now unset since the dma_to_phys()
and phys_to_dma() functions are removed.

Signed-off-by: default avatarJim Quinlan <jim2101024@gmail.com>
Acked-by: default avatarFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: default avatarThomas Bogendoerfer <tsbogend@alpha.franken.de>
parent 6fffb01e

arch/mips/Kconfig

+0 −1
Original line number Diff line number Diff line
@@ -264,7 +264,6 @@ config BMIPS_GENERIC 
	bool "Broadcom Generic BMIPS kernel"

	select ARCH_HAS_RESET_CONTROLLER

	select ARCH_HAS_SYNC_DMA_FOR_CPU_ALL

	select ARCH_HAS_PHYS_TO_DMA

	select BOOT_RAW

	select NO_EXCEPT_FILL

	select USE_OF

arch/mips/bmips/dma.c

+2 −104
Original line number Diff line number Diff line 
/*

 * This file is subject to the terms and conditions of the GNU General Public

 * License.  See the file "COPYING" in the main directory of this archive

 * for more details.

 *

 * Copyright (C) 2014 Kevin Cernekee <cernekee@gmail.com>

 */

// SPDX-License-Identifier: GPL-2.0+



#define pr_fmt(fmt)		"bmips-dma: " fmt



#include <linux/device.h>

#include <linux/dma-direction.h>

#include <linux/dma-direct.h>

#include <linux/init.h>

#include <linux/io.h>

#include <linux/of.h>

#include <linux/printk.h>

#include <linux/slab.h>

#include <linux/types.h>

#include <asm/bmips.h>



/*

 * BCM338x has configurable address translation windows which allow the

 * peripherals' DMA addresses to be different from the Zephyr-visible

 * physical addresses.  e.g. usb_dma_addr = zephyr_pa ^ 0x08000000

 *

 * If the "brcm,ubus" node has a "dma-ranges" property we will enable this

 * translation globally using the provided information.  This implements a

 * very limited subset of "dma-ranges" support and it will probably be

 * replaced by a more generic version later.

 */



struct bmips_dma_range {

	u32			child_addr;

	u32			parent_addr;

	u32			size;

};



static struct bmips_dma_range *bmips_dma_ranges;



#define FLUSH_RAC		0x100



dma_addr_t phys_to_dma(struct device *dev, phys_addr_t pa)

{

	struct bmips_dma_range *r;



	for (r = bmips_dma_ranges; r && r->size; r++) {

		if (pa >= r->child_addr &&

		    pa < (r->child_addr + r->size))

			return pa - r->child_addr + r->parent_addr;

	}

	return pa;

}



phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dma_addr)

{

	struct bmips_dma_range *r;



	for (r = bmips_dma_ranges; r && r->size; r++) {

		if (dma_addr >= r->parent_addr &&

		    dma_addr < (r->parent_addr + r->size))

			return dma_addr - r->parent_addr + r->child_addr;

	}

	return dma_addr;

}

#include <asm/io.h>



void arch_sync_dma_for_cpu_all(void)

{
@@ -79,45 +19,3 @@ void arch_sync_dma_for_cpu_all(void) 
	__raw_writel(cfg | 0x100, cbr + BMIPS_RAC_CONFIG);

	__raw_readl(cbr + BMIPS_RAC_CONFIG);

}
 


static int __init bmips_init_dma_ranges(void)

{

	struct device_node *np =

		of_find_compatible_node(NULL, NULL, "brcm,ubus");

	const __be32 *data;

	struct bmips_dma_range *r;

	int len;



	if (!np)

		return 0;



	data = of_get_property(np, "dma-ranges", &len);

	if (!data)

		goto out_good;



	len /= sizeof(*data) * 3;

	if (!len)

		goto out_bad;



	/* add a dummy (zero) entry at the end as a sentinel */

	bmips_dma_ranges = kcalloc(len + 1, sizeof(struct bmips_dma_range),

				   GFP_KERNEL);

	if (!bmips_dma_ranges)

		goto out_bad;



	for (r = bmips_dma_ranges; len; len--, r++) {

		r->child_addr = be32_to_cpup(data++);

		r->parent_addr = be32_to_cpup(data++);

		r->size = be32_to_cpup(data++);

	}



out_good:

	of_node_put(np);

	return 0;



out_bad:

	pr_err("error parsing dma-ranges property\n");

	of_node_put(np);

	return -EINVAL;

}

arch_initcall(bmips_init_dma_ranges);