u-boot/drivers/mtd/spi/sf_internal.h
Simon Glass b3b60f5912 sf: Support querying write-protect
This feature was dropped from U-Boot some time ago:

   f12f96cfaf (sf: Drop spl_flash_get_sw_write_prot")

However, we do need a way to see if a flash device is write-protected,
since if it is, it may not be possible to write to do (i.e. failing to
write is expected).

I am not sure of the correct layer to implement this, so this patch is a
stab at it. If spi-flash makes sense then I will add to the 'sf' also.

Re the points mentioned in the removal commit:

    1) This kind of requirement can be achieved using existing
       flash operations and flash locking API calls instead of
       making a separate flash API.

Which uclass is this?

    2) Technically there is no real hardware user for this API to
       use in the source tree.

I do want coral (at least) to support this.

    3) Having a flash operations API for simple register read bits
       also make difficult to extend the flash operations.

This new patch only mentions write-protect being on or off, rather than
the actual mechanism.

    4) Instead of touching generic code, it is possible to have
       this functionality inside spinor operations in the form of
       flash hooks or fixups for associated flash chips.

That sounds to me like what drivers are for. But we still need some sort
of API for it to be accessible.

Signed-off-by: Simon Glass <sjg@chromium.org>
2021-03-27 15:04:31 +13:00

96 lines
2.7 KiB
C

/* SPDX-License-Identifier: GPL-2.0+ */
/*
* SPI flash internal definitions
*
* Copyright (C) 2008 Atmel Corporation
* Copyright (C) 2013 Jagannadha Sutradharudu Teki, Xilinx Inc.
*/
#ifndef _SF_INTERNAL_H_
#define _SF_INTERNAL_H_
#include <linux/bitops.h>
#include <linux/types.h>
#include <linux/compiler.h>
#define SPI_NOR_MAX_ID_LEN 6
#define SPI_NOR_MAX_ADDR_WIDTH 4
struct flash_info {
#if !CONFIG_IS_ENABLED(SPI_FLASH_TINY)
char *name;
#endif
/*
* This array stores the ID bytes.
* The first three bytes are the JEDIC ID.
* JEDEC ID zero means "no ID" (mostly older chips).
*/
u8 id[SPI_NOR_MAX_ID_LEN];
u8 id_len;
/* The size listed here is what works with SPINOR_OP_SE, which isn't
* necessarily called a "sector" by the vendor.
*/
unsigned int sector_size;
u16 n_sectors;
u16 page_size;
u16 addr_width;
u32 flags;
#define SECT_4K BIT(0) /* SPINOR_OP_BE_4K works uniformly */
#define SPI_NOR_NO_ERASE BIT(1) /* No erase command needed */
#define SST_WRITE BIT(2) /* use SST byte programming */
#define SPI_NOR_NO_FR BIT(3) /* Can't do fastread */
#define SECT_4K_PMC BIT(4) /* SPINOR_OP_BE_4K_PMC works uniformly */
#define SPI_NOR_DUAL_READ BIT(5) /* Flash supports Dual Read */
#define SPI_NOR_QUAD_READ BIT(6) /* Flash supports Quad Read */
#define USE_FSR BIT(7) /* use flag status register */
#define SPI_NOR_HAS_LOCK BIT(8) /* Flash supports lock/unlock via SR */
#define SPI_NOR_HAS_TB BIT(9) /*
* Flash SR has Top/Bottom (TB) protect
* bit. Must be used with
* SPI_NOR_HAS_LOCK.
*/
#define SPI_S3AN BIT(10) /*
* Xilinx Spartan 3AN In-System Flash
* (MFR cannot be used for probing
* because it has the same value as
* ATMEL flashes)
*/
#define SPI_NOR_4B_OPCODES BIT(11) /*
* Use dedicated 4byte address op codes
* to support memory size above 128Mib.
*/
#define NO_CHIP_ERASE BIT(12) /* Chip does not support chip erase */
#define SPI_NOR_SKIP_SFDP BIT(13) /* Skip parsing of SFDP tables */
#define USE_CLSR BIT(14) /* use CLSR command */
#define SPI_NOR_HAS_SST26LOCK BIT(15) /* Flash supports lock/unlock via BPR */
#define SPI_NOR_OCTAL_READ BIT(16) /* Flash supports Octal Read */
};
extern const struct flash_info spi_nor_ids[];
#define JEDEC_MFR(info) ((info)->id[0])
#define JEDEC_ID(info) (((info)->id[1]) << 8 | ((info)->id[2]))
/* Get software write-protect value (BP bits) */
int spi_flash_cmd_get_sw_write_prot(struct spi_flash *flash);
#if CONFIG_IS_ENABLED(SPI_FLASH_MTD)
int spi_flash_mtd_register(struct spi_flash *flash);
void spi_flash_mtd_unregister(void);
#else
static inline int spi_flash_mtd_register(struct spi_flash *flash)
{
return 0;
}
static inline void spi_flash_mtd_unregister(void)
{
}
#endif
#endif /* _SF_INTERNAL_H_ */