Files
android/drivers/mtd/maps/physmap_of_gemini.c
T
threeeye bc1d038eac REVVL 6 Pro kernel bring-up: full working tree snapshot (2026-09-12)
Squashed backup commit (no shallow-clone history issues) of
xiaomi-mt6833-dev/kernel_xiaomi_mt6833 (lineage-23.2 branch, upstream
commit 9eece662e) plus all fixes applied to get everpal_defconfig building
clean against a modern (GCC 15.2.0) toolchain -- see the previous commit
message on the lineage-23.2 branch (also in this repo history is not
available here since this is a squashed snapshot; full incremental history
lives in the local DL380 checkout and the upstream GitHub remote).

Upstream: https://github.com/xiaomi-mt6833-dev/kernel_xiaomi_mt6833 (lineage-23.2)
2026-09-12 13:36:46 +00:00

103 lines
2.8 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Cortina Systems Gemini OF physmap add-on
* Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org>
*
* This SoC has an elaborate flash control register, so we need to
* detect and set it up when booting on this platform.
*/
#include <linux/export.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/mtd/map.h>
#include <linux/mfd/syscon.h>
#include <linux/regmap.h>
#include <linux/bitops.h>
#include "physmap_of_gemini.h"
/*
* The Flash-relevant parts of the global status register
* These would also be relevant for a NAND driver.
*/
#define GLOBAL_STATUS 0x04
#define FLASH_TYPE_MASK (0x3 << 24)
#define FLASH_TYPE_NAND_2K (0x3 << 24)
#define FLASH_TYPE_NAND_512 (0x2 << 24)
#define FLASH_TYPE_PARALLEL (0x1 << 24)
#define FLASH_TYPE_SERIAL (0x0 << 24)
/* if parallel */
#define FLASH_WIDTH_16BIT (1 << 23) /* else 8 bit */
/* if serial */
#define FLASH_ATMEL (1 << 23) /* else STM */
#define FLASH_SIZE_MASK (0x3 << 21)
#define NAND_256M (0x3 << 21) /* and more */
#define NAND_128M (0x2 << 21)
#define NAND_64M (0x1 << 21)
#define NAND_32M (0x0 << 21)
#define ATMEL_16M (0x3 << 21) /* and more */
#define ATMEL_8M (0x2 << 21)
#define ATMEL_4M_2M (0x1 << 21)
#define ATMEL_1M (0x0 << 21) /* and less */
#define STM_32M (1 << 22) /* and more */
#define STM_16M (0 << 22) /* and less */
#define FLASH_PARALLEL_HIGH_PIN_CNT (1 << 20) /* else low pin cnt */
static const struct of_device_id syscon_match[] = {
{ .compatible = "cortina,gemini-syscon" },
{ },
};
int of_flash_probe_gemini(struct platform_device *pdev,
struct device_node *np,
struct map_info *map)
{
struct regmap *rmap;
struct device *dev = &pdev->dev;
u32 val;
int ret;
/* Multiplatform guard */
if (!of_device_is_compatible(np, "cortina,gemini-flash"))
return 0;
rmap = syscon_regmap_lookup_by_phandle(np, "syscon");
if (IS_ERR(rmap)) {
dev_err(dev, "no syscon\n");
return PTR_ERR(rmap);
}
ret = regmap_read(rmap, GLOBAL_STATUS, &val);
if (ret) {
dev_err(dev, "failed to read global status register\n");
return -ENODEV;
}
dev_dbg(dev, "global status reg: %08x\n", val);
/*
* It would be contradictory if a physmap flash was NOT parallel.
*/
if ((val & FLASH_TYPE_MASK) != FLASH_TYPE_PARALLEL) {
dev_err(dev, "flash is not parallel\n");
return -ENODEV;
}
/*
* Complain if DT data and hardware definition is different.
*/
if (val & FLASH_WIDTH_16BIT) {
if (map->bankwidth != 2)
dev_warn(dev, "flash hardware say flash is 16 bit wide but DT says it is %d bits wide\n",
map->bankwidth * 8);
} else {
if (map->bankwidth != 1)
dev_warn(dev, "flash hardware say flash is 8 bit wide but DT says it is %d bits wide\n",
map->bankwidth * 8);
}
dev_info(&pdev->dev, "initialized Gemini-specific physmap control\n");
return 0;
}