RE: [PATCH 1/2] riscv: defconfig: enable spi nor on Hifive Unleashed A00 board.

[Palmer Dabbelt]

On Tue, 05 May 2020 00:18:45 PDT (-0700), sagar.kadam@xxxxxxxxxx wrote:
> Hello Palmer,
>
> > -----Original Message-----
> > From: Palmer Dabbelt <palmer@xxxxxxxxxxx>
> > Sent: Tuesday, May 5, 2020 3:40 AM
> > To: Sagar Kadam <sagar.kadam@xxxxxxxxxx>
> > Cc: tudor.ambarus@xxxxxxxxxxxxx; miquel.raynal@xxxxxxxxxxx;
> > richard@xxxxxx; vigneshr@xxxxxx; Paul Walmsley
> > <paul.walmsley@xxxxxxxxxx>; linux-riscv@xxxxxxxxxxxxxxxxxxx; linux-
> > kernel@xxxxxxxxxxxxxxx; linux-mtd@xxxxxxxxxxxxxxxxxxx; Sagar Kadam
> > <sagar.kadam@xxxxxxxxxx>
> > Subject: Re: [PATCH 1/2] riscv: defconfig: enable spi nor on Hifive Unleashed
> > A00 board.
> >
> > [External Email] Do not click links or attachments unless you recognize the
> > sender and know the content is safe
> >
> > On Thu, 30 Apr 2020 02:58:51 PDT (-0700), sagar.kadam@xxxxxxxxxx wrote:
> > > Enable MTD based SPI-NOR framework in order to use spi flash available
> > > on HiFive Unleashed A00 board.
> > >
> > > Signed-off-by: Sagar Shrikant Kadam <sagar.kadam@xxxxxxxxxx>
> > > ---
> > >  arch/riscv/configs/defconfig | 2 ++
> > >  1 file changed, 2 insertions(+)
> > >
> > > diff --git a/arch/riscv/configs/defconfig
> > > b/arch/riscv/configs/defconfig index 4da4886..970580b 100644
> > > --- a/arch/riscv/configs/defconfig
> > > +++ b/arch/riscv/configs/defconfig
> > > @@ -80,6 +80,8 @@ CONFIG_USB_STORAGE=y  CONFIG_USB_UAS=y
> > CONFIG_MMC=y
> > > CONFIG_MMC_SPI=y
> > > +CONFIG_MTD=y
> > > +CONFIG_MTD_SPI_NOR=y
> > >  CONFIG_RTC_CLASS=y
> > >  CONFIG_VIRTIO_PCI=y
> > >  CONFIG_VIRTIO_BALLOON=y
> >
> > From the second patch's description I'm assuming that MTD still functions
> > correctly without that change?
>
> Yes Palmer, the second patch is to enable QUAD write to nor flash..
> MTD  function's correctly without second patch.
>
> Using the character interface (/dev/mtd0) mtd_utils (mtd_debug : erase/read/write) work fine.
> We might require CONFIG_MTD_BLOCK, CONFIG_MTD_CMDLINE_PARTS  in order to use MTD partitioning.
> IMHO it can be at user's choice weather to use flash partitions or not, so I have not enabled. Please let me 
> know if I should enable these features as well.

Looks like arm64 has these:

arch/arm64/configs/defconfig:CONFIG_MTD=y
arch/arm64/configs/defconfig:CONFIG_MTD_BLOCK=y
arch/arm64/configs/defconfig:CONFIG_MTD_CFI=y
arch/arm64/configs/defconfig:CONFIG_MTD_CFI_ADV_OPTIONS=y
arch/arm64/configs/defconfig:CONFIG_MTD_CFI_INTELEXT=y
arch/arm64/configs/defconfig:CONFIG_MTD_CFI_AMDSTD=y
arch/arm64/configs/defconfig:CONFIG_MTD_CFI_STAA=y
arch/arm64/configs/defconfig:CONFIG_MTD_PHYSMAP=y
arch/arm64/configs/defconfig:CONFIG_MTD_PHYSMAP_OF=y
arch/arm64/configs/defconfig:CONFIG_MTD_DATAFLASH=y
arch/arm64/configs/defconfig:CONFIG_MTD_SST25L=y
arch/arm64/configs/defconfig:CONFIG_MTD_RAW_NAND=y
arch/arm64/configs/defconfig:CONFIG_MTD_NAND_DENALI_DT=y
arch/arm64/configs/defconfig:CONFIG_MTD_NAND_MARVELL=y
arch/arm64/configs/defconfig:CONFIG_MTD_NAND_FSL_IFC=y
arch/arm64/configs/defconfig:CONFIG_MTD_NAND_QCOM=y
arch/arm64/configs/defconfig:CONFIG_MTD_SPI_NOR=y

so I think we're good with just what you have here: MTD_BLOCK doesn't seem that
useful, and the rest are drivers.  That said, these (along with SPI and
SPI_SIFIVE) should really be in Kconfig.socs rather than defconfig.  Can you
send a patch that does that?

> To demonstrate a bit more with linux 5.7-rc3 
>
> Specify on U-boot prompt:
> # setenv bootargs "root=/dev/ram rw console=ttySIF0 mtdparts=spi0.0:1024k(loader1),4096K(loader2),26M(rootfs)"
>
> After booting linux will enumerate mtd partitions:
> # cat /proc/mtd
> dev:    size   erasesize  name
> mtd0: 00100000 00001000 "loader1"
> mtd1: 00400000 00001000 "loader2"
> mtd2: 01a00000 00001000 "rootfs"
>
> # cat /proc/partitions
> major minor  #blocks  name
>   31        0       1024 mtdblock0
>   31        1       4096 mtdblock1
>   31        2      26624 mtdblock2
>
> #Format mtdblock2 with mkfs.ext3/4 and mount results in
> # mkfs.ext3 /dev/mtdblock2
> mke2fs 1.44.5 (15-Dec-2018)
> /dev/mtdblock2 contains a ext3 file system
>         last mounted on /mnt on Thu Jan  1 00:00:14 1970
> Proceed anyway? (y,N) y
> Creating filesystem with 26624 1k blocks and 6656 inodes
> Filesystem UUID: 1b09252d-e313-430c-9ecb-79b0cef003ca
> Superblock backups stored on blocks:
>         8193, 24577
>
> Allocating group tables: done
> Writing inode tables: done
> Creating journal (1024 blocks): done
> Writing superblocks and filesystem accounting information: done
>
> # mount
> none on / type rootfs (rw)
> proc on /proc type proc (rw,relatime)
> devpts on /dev/pts type devpts (rw,relatime,gid=5,mode=620,ptmxmode=666)
> tmpfs on /dev/shm type tmpfs (rw,relatime,mode=777)
> tmpfs on /tmp type tmpfs (rw,relatime)
> tmpfs on /run type tmpfs (rw,nosuid,nodev,relatime,mode=755)
> sysfs on /sys type sysfs (rw,relatime)
> /dev/mtdblock2 on /mnt type ext3 (rw,relatime)
>
> Thanks & BR,
> Sagar Kadam