[U-Boot] [V4 2/2] sf: Turn SPI flash into 3-Byte address mode on Micron chips

[Hou Zhiqiang]

> -----Original Message-----
> From: Jagan Teki [mailto:jteki at openedev.com]
> Sent: 2015年8月11日 1:10
> To: Hou Zhiqiang-B48286
> Cc: u-boot at lists.denx.de; Sun York-R58495
> Subject: Re: [U-Boot] [V4 2/2] sf: Turn SPI flash into 3-Byte address
> mode on Micron chips
> 
> On 10 August 2015 at 08:28, Hou Zhiqiang <B48286 at freescale.com> wrote:
> > Hi Jagan,
> >
> > Do you have any feedback?
> >
> >> -----Original Message-----
> >> From: Zhiqiang Hou [mailto:B48286 at freescale.com]
> >> Sent: 2015年7月23日 17:54
> >> To: u-boot at lists.denx.de; jteki at openedev.com
> >> Cc: Sun York-R58495; Hu Mingkai-B21284; Hou Zhiqiang-B48286
> >> Subject: [V4 2/2] sf: Turn SPI flash into 3-Byte address mode on
> >> Micron chips
> >>
> >> From: Hou Zhiqiang <B48286 at freescale.com>
> >>
> >> For more than 16MiB Micron chips, there are 3-Byte and 4-Byte address
> >> mode, and only the 3-Byte address mode is supported in u-boot.
> >> So, reset the SPI flash to 3-Byte address mode in probe to ensure the
> >> SPI flash work correctly, because it may be in 4-Byte address mode
> >> after warm boot.
> >>
> >> Signed-off-by: Hou Zhiqiang <B48286 at freescale.com>
> >> ---
> >>  drivers/mtd/spi/sf_internal.h |  8 ++++++++
> >>  drivers/mtd/spi/sf_ops.c      | 24 ++++++++++++++++++++++++
> >>  drivers/mtd/spi/sf_probe.c    |  5 +++++
> >>  3 files changed, 37 insertions(+)
> >>
> >> diff --git a/drivers/mtd/spi/sf_internal.h
> >> b/drivers/mtd/spi/sf_internal.h index 703d4a7..3d7ed24 100644
> >> --- a/drivers/mtd/spi/sf_internal.h
> >> +++ b/drivers/mtd/spi/sf_internal.h
> >> @@ -75,6 +75,10 @@ enum {
> >>  #define CMD_FLAG_STATUS                      0x70
> >>  #define CMD_CLEAR_FLAG_STATUS                0x50
> >>
> >> +/* Used for Macronix and Winbond flashes */
> >> +#define      CMD_ENTER_4B_ADDR               0xB7
> >> +#define      CMD_EXIT_4B_ADDR                0xE9
> >> +
> >>  /* Read commands */
> >>  #define CMD_READ_ARRAY_SLOW          0x03
> >>  #define CMD_READ_ARRAY_FAST          0x0b
> >> @@ -227,6 +231,10 @@ int spi_flash_read_common(struct spi_flash
> >> *flash, const u8 *cmd,  int spi_flash_cmd_read_ops(struct spi_flash
> >> *flash, u32 offset,
> >>               size_t len, void *data);
> >>
> >> +#if defined(CONFIG_SPI_FLASH_STMICRO) int
> >> +spi_flash_cmd_4B_addr_switch(struct spi_flash *flash, int enable);
> >> +#endif
> >> +
> >>  #ifdef CONFIG_SPI_FLASH_MTD
> >>  int spi_flash_mtd_register(struct spi_flash *flash);  void
> >> spi_flash_mtd_unregister(void); diff --git a/drivers/mtd/spi/sf_ops.c
> >> b/drivers/mtd/spi/sf_ops.c index cbb9f00..1ce14d1 100644
> >> --- a/drivers/mtd/spi/sf_ops.c
> >> +++ b/drivers/mtd/spi/sf_ops.c
> >> @@ -93,6 +93,30 @@ int spi_flash_cmd_write_config(struct spi_flash
> >> *flash,
> >> u8 wc)  }  #endif
> >>
> >> +#if defined(CONFIG_SPI_FLASH_STMICRO) int
> >> +spi_flash_cmd_4B_addr_switch(struct spi_flash *flash, int enable) {
> >> +     int ret;
> >> +     u8 cmd;
> >> +
> >> +     cmd = enable ? CMD_ENTER_4B_ADDR : CMD_EXIT_4B_ADDR;
> >> +
> >> +     ret = spi_claim_bus(flash->spi);
> >> +     if (ret) {
> >> +             debug("SF: unable to claim SPI bus\n");
> >> +             return ret;
> >> +     }
> >> +
> >> +     ret = spi_flash_cmd_write_enable(flash);
> >> +     if (ret < 0) {
> >> +             debug("SF: enabling write failed\n");
> >> +             return ret;
> >> +     }
> >> +
> >> +     return spi_flash_cmd(flash->spi, cmd, NULL, 0); } #endif
> >> +
> >>  #ifdef CONFIG_SPI_FLASH_BAR
> >>  static int spi_flash_cmd_bankaddr_write(struct spi_flash *flash, u8
> >> bank_sel)  { diff --git a/drivers/mtd/spi/sf_probe.c
> >> b/drivers/mtd/spi/sf_probe.c index e0283dc..5ba7dde 100644
> >> --- a/drivers/mtd/spi/sf_probe.c
> >> +++ b/drivers/mtd/spi/sf_probe.c
> >> @@ -231,6 +231,11 @@ static int spi_flash_validate_params(struct
> >> spi_slave *spi, u8 *idcode,  #ifdef CONFIG_SPI_FLASH_STMICRO
> >>       if (params->flags & E_FSR)
> >>               flash->poll_cmd = CMD_FLAG_STATUS;
> >> +
> >> +     if (flash->size > SPI_FLASH_16MB_BOUN) {
> >> +             if (spi_flash_cmd_4B_addr_switch(flash, 0) < 0)
> >> +                     debug("SF: enter 3B address mode failed\n");
> >> +     }
> 
> Don't add STMICRO specific macro, add something like 1. define a macro
> CONFIG_SF_EN4B 2. probe check for size > 16MiB, and try to set the 4byte
> addressing.
> 

Thanks for your suggestions and Patch version 5 has been pushed to upstream.
In patch version 5:
Removed the STMICRO specific macro and add Spansion chips address mode switch
support.

Force the chips (>16MiB) switch to 3-Byte address mode in probe, due to the 4-Byte
Mode isn't supported so far in U-Boot, so didn't define a macro CONFIG_SF_EN4B,
and read/write >16MiB chips by the extend address register.

> >>  #endif
> >>
> >>       /* Configure the BAR - discover bank cmds and read current bank
> >> */
> >> --
> >> 2.1.0.27.g96db324
> >
> 
> thanks!
> --
> Jagan | openedev.

Thanks,
Zhiqiang