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c2fc6b6947
The DT of_device.h and of_platform.h date back to the separate of_platform_bus_type before it was merged into the regular platform bus. As part of that merge prepping Arm DT support 13 years ago, they "temporarily" include each other. They also include platform_device.h and of.h. As a result, there's a pretty much random mix of those include files used throughout the tree. In order to detangle these headers and replace the implicit includes with struct declarations, users need to explicitly include the correct includes. Signed-off-by: Rob Herring <robh@kernel.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Link: https://lore.kernel.org/linux-mtd/20230714174751.4060439-1-robh@kernel.org
125 lines
2.9 KiB
C
125 lines
2.9 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Copyright (C) 2020 BAIKAL ELECTRONICS, JSC
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*
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* Authors:
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* Serge Semin <Sergey.Semin@baikalelectronics.ru>
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*
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* Baikal-T1 Physically Mapped Internal ROM driver
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*/
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#include <linux/bits.h>
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#include <linux/device.h>
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#include <linux/kernel.h>
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#include <linux/mtd/map.h>
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#include <linux/mtd/xip.h>
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#include <linux/mux/consumer.h>
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#include <linux/of.h>
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#include <linux/platform_device.h>
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#include <linux/string.h>
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#include <linux/types.h>
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#include "physmap-bt1-rom.h"
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/*
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* Baikal-T1 SoC ROMs are only accessible by the dword-aligned instructions.
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* We have to take this into account when implementing the data read-methods.
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* Note there is no need in bothering with endianness, since both Baikal-T1
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* CPU and MMIO are LE.
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*/
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static map_word __xipram bt1_rom_map_read(struct map_info *map,
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unsigned long ofs)
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{
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void __iomem *src = map->virt + ofs;
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unsigned int shift;
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map_word ret;
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u32 data;
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/* Read data within offset dword. */
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shift = (uintptr_t)src & 0x3;
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data = readl_relaxed(src - shift);
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if (!shift) {
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ret.x[0] = data;
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return ret;
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}
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ret.x[0] = data >> (shift * BITS_PER_BYTE);
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/* Read data from the next dword. */
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shift = 4 - shift;
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if (ofs + shift >= map->size)
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return ret;
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data = readl_relaxed(src + shift);
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ret.x[0] |= data << (shift * BITS_PER_BYTE);
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return ret;
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}
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static void __xipram bt1_rom_map_copy_from(struct map_info *map,
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void *to, unsigned long from,
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ssize_t len)
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{
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void __iomem *src = map->virt + from;
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unsigned int shift, chunk;
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u32 data;
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if (len <= 0 || from >= map->size)
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return;
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/* Make sure we don't go over the map limit. */
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len = min_t(ssize_t, map->size - from, len);
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/*
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* Since requested data size can be pretty big we have to implement
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* the copy procedure as optimal as possible. That's why it's split
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* up into the next three stages: unaligned head, aligned body,
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* unaligned tail.
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*/
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shift = (uintptr_t)src & 0x3;
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if (shift) {
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chunk = min_t(ssize_t, 4 - shift, len);
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data = readl_relaxed(src - shift);
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memcpy(to, (char *)&data + shift, chunk);
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src += chunk;
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to += chunk;
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len -= chunk;
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}
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while (len >= 4) {
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data = readl_relaxed(src);
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memcpy(to, &data, 4);
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src += 4;
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to += 4;
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len -= 4;
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}
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if (len) {
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data = readl_relaxed(src);
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memcpy(to, &data, len);
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}
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}
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int of_flash_probe_bt1_rom(struct platform_device *pdev,
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struct device_node *np,
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struct map_info *map)
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{
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struct device *dev = &pdev->dev;
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/* It's supposed to be read-only MTD. */
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if (!of_device_is_compatible(np, "mtd-rom")) {
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dev_info(dev, "No mtd-rom compatible string\n");
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return 0;
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}
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/* Multiplatform guard. */
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if (!of_device_is_compatible(np, "baikal,bt1-int-rom"))
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return 0;
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/* Sanity check the device parameters retrieved from DTB. */
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if (map->bankwidth != 4)
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dev_warn(dev, "Bank width is supposed to be 32 bits wide\n");
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map->read = bt1_rom_map_read;
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map->copy_from = bt1_rom_map_copy_from;
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return 0;
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}
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