[PATCH v2 0/4] mtd: pxa3xx_nand: rework the timing setup

[Ezequiel Garcia]

On 3 August 2015 at 01:44, Robert Jarzmik <robert.jarzmik at free.fr> wrote:
> Ezequiel Garcia <ezequiel at vanguardiasur.com.ar> writes:
>
>> Just tested linux-next (hence *without* the patchset) and I see
>> the same "Wait time out". In other words, pxa3xx-nand is broken
>> on PXA :/
>>
>> Interestingly, the culprit doesn't seem to be in pxa3xx-nand itself.
>> Reverting the recent commits on pxa3xx-nand doesn't help.
>>
>> ce914e6 mtd: nand: pxa3xx: fix build on ARM64
>> afca11e mtd: nand: pxa3xx: Switch FIFO draining to jiffies-based timeout
>> e5860c1 mtd: pxa3xx_nand: cleanup wait_for_completion handling
>> 7c2f717 mtd: pxa3xx_nand: initialiaze pxa3xx_flash_ids to 0
>> ed446cc Merge MTD updates into -next
>> e423c90 mtd: pxa3xx_nand: fix driver when num_cs is 0
>> 2454225 mtd: pxa3xx-nand: handle PIO in threaded interrupt
>> 8dad038 mtd: nand: pxa3xx: Fix PIO FIFO draining
>> b7e46062 mtd: pxa3xx_nand: make the driver work on big-endian systems
>> 5b3e507 mtd: nand: pxa3xx: Use ECC strength and step size devicetree binding
>> eee0166 mtd: nand: pxa3xx: Clean pxa_ecc_init() error handling
>> 17754ad mtd: nand: pxa3xx: Make of_device_id array const
>> e634ce5 mtd: nand: pxa3xx: Print actual ECC strength in error message
>>
>> Yet v3.18 succeeds to pass a few NAND blocks on nandtest.
>>
>> Robert: any ideas?
> Actually yes, I worked on that this weekend.
> Would you try the following patch [1] to see if it works for you ?
>
> The issue I see is that :
>  - there is a bug in the clk driver for pxa3xx I introduced (CKEN_AB)
>  - and shutting down the GCU clock prevents the NAND from working (I can't
>  explain that one yet)
>

IIRC, on Armada 370/XP SoCs we have two clocks feeding the NAND
controller: one for the NAND logic (not really sure?), and one for the
NAND ECC engine.

Maybe the GCU feeds the ECC?

> Cheers.
>
> --
> Robert
>
> [1] Clocks patch

Ah, good. I was almost sure it was the clock (after trying a bunch of
other stuff it was the only big change left).

I'll try this and will let you know.

> ---8>---
> diff --git a/drivers/clk/pxa/clk-pxa3xx.c b/drivers/clk/pxa/clk-pxa3xx.c
> index c677b9ab5367..a47a0c40f937 100644
> --- a/drivers/clk/pxa/clk-pxa3xx.c
> +++ b/drivers/clk/pxa/clk-pxa3xx.c
> @@ -126,7 +126,7 @@ PARENTS(pxa3xx_ac97_bus) = { "ring_osc_60mhz", "ac97" };
>  PARENTS(pxa3xx_sbus) = { "ring_osc_60mhz", "system_bus" };
>  PARENTS(pxa3xx_smemcbus) = { "ring_osc_60mhz", "smemc" };
>
> -#define CKEN_AB(bit) ((CKEN_ ## bit > 31) ? &CKENA : &CKENB)
> +#define CKEN_AB(bit) ((CKEN_ ## bit > 31) ? &CKENB : &CKENA)
>  #define PXA3XX_CKEN(dev_id, con_id, parents, mult_lp, div_lp, mult_hp, \
>                     div_hp, bit, is_lp, flags)                          \
>         PXA_CKEN(dev_id, con_id, bit, parents, mult_lp, div_lp,         \
> @@ -136,6 +136,10 @@ PARENTS(pxa3xx_smemcbus) = { "ring_osc_60mhz", "smemc" };
>                          mult_hp, div_hp, delay)                        \
>         PXA3XX_CKEN(dev_id, con_id, pxa3xx_pbus_parents, mult_lp,       \
>                     div_lp, mult_hp, div_hp, bit, pxa3xx_is_ring_osc_forced, 0)
> +#define PXA3XX_PBUS_CKENF(dev_id, con_id, bit, mult_lp, div_lp,                \
> +                         mult_hp, div_hp, delay, flag)                 \
> +       PXA3XX_CKEN(dev_id, con_id, pxa3xx_pbus_parents, mult_lp,       \
> +                   div_lp, mult_hp, div_hp, bit, pxa3xx_is_ring_osc_forced, flag)
>  #define PXA3XX_CKEN_1RATE(dev_id, con_id, bit, parents)                        \
>         PXA_CKEN_1RATE(dev_id, con_id, bit, parents,                    \
>                        CKEN_AB(bit), (CKEN_ ## bit % 32), 0)
> @@ -173,13 +177,13 @@ static struct desc_clk_cken pxa3xx_clocks[] __initdata = {
>
>  static struct desc_clk_cken pxa300_310_clocks[] __initdata = {
>
> -       PXA3XX_PBUS_CKEN("pxa3xx-gcu", NULL, PXA300_GCU, 1, 1, 1, 1, 0),
> -       PXA3XX_PBUS_CKEN("pxa3xx-nand", NULL, NAND, 1, 2, 1, 4, 0),
> +       PXA3XX_PBUS_CKENF("pxa3xx-gcu", NULL, PXA300_GCU, 1, 1, 1, 1, 0, CLK_IGNORE_UNUSED),
> +       PXA3XX_PBUS_CKENF("pxa3xx-nand", NULL, NAND, 1, 2, 1, 4, 0, CLK_IGNORE_UNUSED),
>         PXA3XX_CKEN_1RATE("pxa3xx-gpio", NULL, GPIO, pxa3xx_13MHz_bus_parents),
>  };
>
>  static struct desc_clk_cken pxa320_clocks[] __initdata = {
> -       PXA3XX_PBUS_CKEN("pxa3xx-nand", NULL, NAND, 1, 2, 1, 6, 0),
> +       PXA3XX_PBUS_CKENF("pxa3xx-nand", NULL, NAND, 1, 2, 1, 4, 0, CLK_IGNORE_UNUSED),
>         PXA3XX_PBUS_CKEN("pxa3xx-gcu", NULL, PXA320_GCU, 1, 1, 1, 1, 0),
>         PXA3XX_CKEN_1RATE("pxa3xx-gpio", NULL, GPIO, pxa3xx_13MHz_bus_parents),
>  };
> @@ -187,7 +191,7 @@ static struct desc_clk_cken pxa320_clocks[] __initdata = {
>  static struct desc_clk_cken pxa93x_clocks[] __initdata = {
>
>         PXA3XX_PBUS_CKEN("pxa3xx-gcu", NULL, PXA300_GCU, 1, 1, 1, 1, 0),
> -       PXA3XX_PBUS_CKEN("pxa3xx-nand", NULL, NAND, 1, 2, 1, 4, 0),
> +       PXA3XX_PBUS_CKENF("pxa3xx-nand", NULL, NAND, 1, 2, 1, 4, 0, CLK_IGNORE_UNUSED),
>         PXA3XX_CKEN_1RATE("pxa93x-gpio", NULL, GPIO, pxa3xx_13MHz_bus_parents),
>  };
>



-- 
Ezequiel García, VanguardiaSur
www.vanguardiasur.com.ar