On Wed, Jan 22, 2020 at 4:03 AM Marek Vasut wrote:
>
> The register values programmed into the Denali NAND IP are not preserved
> when the IP reset signal is asserted. Depending on whether the Denali NAND
> IP implementation uses HW-assisted bootstrap or not, some of the register
> values are restored automatically after the IP is released from reset.
>
> If HW-assisted bootstrap is used, only RB_PIN_ENABLED, CHIP_ENABLE_DONT_CARE,
> SPARE_AREA_SKIP_BYTES and SPARE_AREA_MARKER need to be restored after reset,
> this is the case on Altera SoCFPGA. Otherwise, many more registers must be
> restored. Since mainline Linux currently does not handle this correctly, do
> not reset the Denali NAND IP before booting Linux. This permits Linux to use
> the register values retained in the Denali NAND IP and thus correctly access
> the NAND.
>
> Fixes: ed784ac3822b ("mtd: rawnand: denali: add reset handling")
> Signed-off-by: Marek Vasut
> Cc: Masahiro Yamada
> Cc: Simon Goldschmidt
> ---
I talked to Marek off-list, and he acked me
to reword the commit log like follows when applied.
-->8--
commit 9a230b0072504511454912a9e301f0beabc270c6 (HEAD -> uniphier,
origin/uniphier)
Author: Marek Vasut
Date: Tue Jan 21 20:03:11 2020 +0100
mtd: rawnand: denali: Do not reset the block before booting the kernel
The Denali NAND driver in mainline Linux currently cannot deassert the
reset. The upcoming Linux 5.6 will support the reset controlling, and
also set up SPARE_AREA_SKIP_BYTES correctly. So, the Denali driver in
the future kernel will work without relying on any bootloader or firmware.
However, we still need to take care of stable kernel versions for a while.
U-boot should not assert the reset of this controller.
Fixes: ed784ac3822b ("mtd: rawnand: denali: add reset handling")
Signed-off-by: Marek Vasut
[yamada.masahiro: reword the commit description]
Signed-off-by: Masahiro Yamada
-->8--
Applied to u-boot-uniphier.
Thanks.
> V2: - Make resets into local variable
> - Update patch description
> ---
> drivers/mtd/nand/raw/denali.h| 2 --
> drivers/mtd/nand/raw/denali_dt.c | 15 ---
> 2 files changed, 4 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/mtd/nand/raw/denali.h b/drivers/mtd/nand/raw/denali.h
> index 63ae828768..019deda094 100644
> --- a/drivers/mtd/nand/raw/denali.h
> +++ b/drivers/mtd/nand/raw/denali.h
> @@ -10,7 +10,6 @@
> #include
> #include
> #include
> -#include
>
> #define DEVICE_RESET 0x0
> #define DEVICE_RESET__BANK(bank) BIT(bank)
> @@ -316,7 +315,6 @@ struct denali_nand_info {
> void (*host_write)(struct denali_nand_info *denali, u32 addr, u32
> data);
> void (*setup_dma)(struct denali_nand_info *denali, dma_addr_t
> dma_addr,
> int page, int write);
> - struct reset_ctl_bulk resets;
> };
>
> #define DENALI_CAP_HW_ECC_FIXUPBIT(0)
> diff --git a/drivers/mtd/nand/raw/denali_dt.c
> b/drivers/mtd/nand/raw/denali_dt.c
> index b1e14982c4..91d0f20aae 100644
> --- a/drivers/mtd/nand/raw/denali_dt.c
> +++ b/drivers/mtd/nand/raw/denali_dt.c
> @@ -9,6 +9,7 @@
> #include
> #include
> #include
> +#include
>
> #include "denali.h"
>
> @@ -63,6 +64,7 @@ static int denali_dt_probe(struct udevice *dev)
> struct denali_nand_info *denali = dev_get_priv(dev);
> const struct denali_dt_data *data;
> struct clk clk, clk_x, clk_ecc;
> + struct reset_ctl_bulk resets;
> struct resource res;
> int ret;
>
> @@ -133,30 +135,21 @@ static int denali_dt_probe(struct udevice *dev)
> denali->clk_x_rate = 2;
> }
>
> - ret = reset_get_bulk(dev, &denali->resets);
> + ret = reset_get_bulk(dev, &resets);
> if (ret)
> dev_warn(dev, "Can't get reset: %d\n", ret);
> else
> - reset_deassert_bulk(&denali->resets);
> + reset_deassert_bulk(&resets);
>
> return denali_init(denali);
> }
>
> -static int denali_dt_remove(struct udevice *dev)
> -{
> - struct denali_nand_info *denali = dev_get_priv(dev);
> -
> - return reset_release_bulk(&denali->resets);
> -}
> -
> U_BOOT_DRIVER(denali_nand_dt) = {
> .name = "denali-nand-dt",
> .id = UCLASS_MISC,
> .of_match = denali_nand_dt_ids,
> .probe = denali_dt_probe,
> .priv_auto_alloc_size = sizeof(struct denali_nand_info),
> - .remove = denali_dt_remove,
> - .flags = DM_FLAG_OS_PREPARE,
> };
>
> void board_nand_init(void)
> --
> 2.24.1
>
--
Best Regards
Masahiro Yamada
