[u-boot][PATCH 10/14] mtd: rawnand: omap_gpmc: support u-boot driver model
Adam Ford
aford173 at gmail.com
Thu Oct 13 13:17:04 CEST 2022
On Wed, Oct 12, 2022 at 6:42 AM Adam Ford <aford173 at gmail.com> wrote:
>
> On Wed, Oct 12, 2022 at 1:22 AM Roger Quadros <rogerq at kernel.org> wrote:
> >
> > Hi Adam,
> >
> > On 11/10/2022 18:01, Adam Ford wrote:
> > > On Tue, Oct 11, 2022 at 6:52 AM Roger Quadros <rogerq at kernel.org> wrote:
> > >>
> > >> Adds driver model support.
> > >>
> > >> We need to be able to self initialize the NAND controller/chip
> > >> at probe and so enable CONFIG_SYS_NAND_SELF_INIT.
> > >>
> > >> Doing so requires nand_register() API which is provided by nand.c
> > >> and needs to be enabled during SPL build via CONFIG_SPL_NAND_INIT.
> > >> But nand.c also provides nand_init() so we need to get rid of nand_init()
> > >> in omap_gpmc driver if CONFIG_SPL_NAND_INIT is set.
> > >>
> > >> Signed-off-by: Roger Quadros <rogerq at kernel.org>
> > >> ---
> > >> drivers/mtd/nand/raw/Kconfig | 1 +
> > >> drivers/mtd/nand/raw/omap_gpmc.c | 55 +++++++++++++++++++++++++++++++-
> > >> 2 files changed, 55 insertions(+), 1 deletion(-)
> > >>
> > >> diff --git a/drivers/mtd/nand/raw/Kconfig b/drivers/mtd/nand/raw/Kconfig
> > >> index bc5cabdfc2..1d23144ce4 100644
> > >> --- a/drivers/mtd/nand/raw/Kconfig
> > >> +++ b/drivers/mtd/nand/raw/Kconfig
> > >> @@ -190,6 +190,7 @@ config NAND_LPC32XX_SLC
> > >> config NAND_OMAP_GPMC
> > >> bool "Support OMAP GPMC NAND controller"
> > >> depends on ARCH_OMAP2PLUS || ARCH_KEYSTONE || ARCH_K3
> > >> + select SYS_NAND_SELF_INIT if ARCH_K3
> > >
> > > I have a question about this down below.
> > >
> > >> help
> > >> Enables omap_gpmc.c driver for OMAPx and AMxxxx platforms.
> > >> GPMC controller is used for parallel NAND flash devices, and can
> > >> diff --git a/drivers/mtd/nand/raw/omap_gpmc.c b/drivers/mtd/nand/raw/omap_gpmc.c
> > >> index e772a914c8..7192ca9e5a 100644
> > >> --- a/drivers/mtd/nand/raw/omap_gpmc.c
> > >> +++ b/drivers/mtd/nand/raw/omap_gpmc.c
> > >> @@ -7,6 +7,7 @@
> > >> #include <common.h>
> > >> #include <log.h>
> > >> #include <asm/io.h>
> > >> +#include <dm/uclass.h>
> > >> #include <linux/errno.h>
> > >>
> > >> #ifdef CONFIG_ARCH_OMAP2PLUS
> > >> @@ -1121,7 +1122,7 @@ int __maybe_unused omap_nand_switch_ecc(uint32_t hardware, uint32_t eccstrength)
> > >> * nand_scan about special functionality. See the defines for further
> > >> * explanation
> > >> */
> > >> -int board_nand_init(struct nand_chip *nand)
> > >> +int gpmc_nand_init(struct nand_chip *nand)
> > >> {
> > >> int32_t gpmc_config = 0;
> > >> int cs = cs_next++;
> > >> @@ -1201,3 +1202,55 @@ int board_nand_init(struct nand_chip *nand)
> > >>
> > >> return 0;
> > >> }
> > >> +
> > >> +static struct nand_chip *nand_chip; /* First NAND chip for SPL use only */
> > >> +
> > >> +#if CONFIG_IS_ENABLED(SYS_NAND_SELF_INIT)
> > >> +
> > >> +static int gpmc_nand_probe(struct udevice *dev)
> > >> +{
> > >> + struct nand_chip *nand = dev_get_priv(dev);
> > >> + struct mtd_info *mtd = nand_to_mtd(nand);
> > >> + int ret;
> > >> +
> > >> + gpmc_nand_init(nand);
> > >> +
> > >> + ret = nand_scan(mtd, CONFIG_SYS_NAND_MAX_CHIPS);
> > >> + if (ret)
> > >> + return ret;
> > >> +
> > >> + ret = nand_register(0, mtd);
> > >> + if (ret)
> > >> + return ret;
> > >> +
> > >> + if (!nand_chip)
> > >> + nand_chip = nand;
> > >> +
> > >> + return 0;
> > >> +}
> > >> +
> > >> +static const struct udevice_id gpmc_nand_ids[] = {
> > >> + { .compatible = "ti,am64-nand" },
> > >> + { .compatible = "ti,omap2-nand" },
> > >
> > > The gpmc_nand_ids reference to omap2, but it's encapsulated inside the
> > > SYS_NAND_SELF_INIT ifdef which appears to only be set if K3. Should
> > > this code be expected to work on OMAP2? I don't think K3 is set for
> > > OMAP2+. If so, should the SYS_NAND_SELF_INIT be selected if OMAP2 is
> > > selected?
> >
> > We want to eventually get this working using driver model and SYS_NAND_SELF_INIT
> > for OMAP2 as well but just that I didn't work on it yet or test it.
> >
> > One challenge is that OMAP2 boards tend to either select nand_spl_simple.c
> > or am335x_spl_bch.c for NAND support at SPL.
> >
> > We will need to figure out if it is possible to use CONFIG_SPL_NAND_INIT
> > and this driver instead.
> > One issue might be that everything doesn't fit in resources available at SPL?
>
> On my board the GPMC runs more than just NAND. I am hoping to get the
> GPMC driver working in U-Boot first then in SPL (assuming it fits). I
> have LTO enabled on my DM3730, so I am hoping it might help make some
> room. I am hoping that once the NAND is working that the GPMC driver
> can be used in U-Boot to handle the configuration of the bus for
> handling Ethernet, so some of the quirks and manual board file
> configuration can be removed.
> >
> > >
> > > I have a DM3730 that I can test with this. Do you have a repo I can
> >
> > That would be great. Thanks!
I haven't spend a lot of time, but here is what I have so far:
U-Boot 2022.10-rc4-gf499f45d18-dirty (Oct 13 2022 - 05:33:33 -0500)
OMAP3630/3730-GP ES1.2, CPU-OPP2, L3-200MHz, Max CPU Clock 1 GHz
Model: LogicPD Zoom DM3730 Torpedo + Wireless Development Kit
DRAM: 256 MiB
Error binding driver 'gpmc-nand': -96
Some drivers failed to bind
Error binding driver 'ti-gpmc': -96
Some drivers failed to bind
Error binding driver 'simple_bus': -96
Some drivers failed to bind
initcall sequence 8ffde84c failed at call 8011705d (err=-96)
### ERROR ### Please RESET the board ###
There was a small conflict with arch/arm/mach-omap2/mem-common.c
where I needed to remove a reference to gpmc_cfg to let it compile.
+#ifndef CONFIG_TI_GPMC
const struct gpmc *gpmc_cfg = (struct gpmc *)GPMC_BASE;
+#endif
After that, I had to enable CONFIG_CLK and CONFIG_CLK_TI_GATE, but I
am not sure it's sufficient. I haven't had enough time to check to
see if the OMAP3 clock drivers are fully supported in U-Boot or not.
I am guessing they'll need to be functional enough to fetch the fck so
the GPMC controller knows how fast it's running to properly calculate
the timings.
Do you have any suggestions on what I should do to diagnose the -96
errors on all the GPMC sub-nodes?
adam
> >
> > > point to to test? If not, I'll pull the series from patchwork, but I
> > > need to know what branch to use as a starting point.
> >
> > You can use this Repo as reference.
> > https://github.com/rogerq/u-boot/commits/for-v2023.01/am64-nand-base-1.0-test
> >
>
> Thanks!
>
> > It has a few patches on top consisting of device tree and u-boot configuration
> > for AM64 platform. You can ignore the last 2 patches as they are only for a
> > workaround on early AM64 boards.
> >
> > If you hit any hurdles, we can discuss how to resolve.
>
> I'll just pull in the branch and build for my DM3730 then start
> enabling and disabling stuff. I haven't checked how big SPL is, but
> SPL keeps growing instead of shrinking. OF_PLATDATA might be an
> option if it doesn't fit in SPL, but I was hoping to avoid that.
>
> adam
> >
> > >
> > > thanks,
> > >
> > > adam
> > >
> > >> + { }
> > >> +};
> > >> +
> > >> +U_BOOT_DRIVER(gpmc_nand) = {
> > >> + .name = "gpmc-nand",
> > >> + .id = UCLASS_MTD,
> > >> + .of_match = gpmc_nand_ids,
> > >> + .probe = gpmc_nand_probe,
> > >> + .priv_auto = sizeof(struct nand_chip),
> > >> +};
> > >> +
> > >> +void board_nand_init(void)
> > >> +{
> > >> + struct udevice *dev;
> > >> + int ret;
> > >> +
> > >> + ret = uclass_get_device_by_driver(UCLASS_MTD,
> > >> + DM_DRIVER_GET(gpmc_nand), &dev);
> > >> + if (ret && ret != -ENODEV)
> > >> + pr_err("%s: Failed to get GPMC device: %d\n", __func__, ret);
> > >> +}
> > >> +#endif /* CONFIG_SYS_NAND_SELF_INIT */
> > >> --
> > >> 2.17.1
> > >>
> >
> > cheers,
> > -roger
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