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

From: Robert Jarzmik
Date: Mon Aug 03 2015 - 00:48:25 EST


Ezequiel Garcia <ezequiel@xxxxxxxxxxxxxxxxxxxx> 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)

Cheers.

--
Robert

[1] Clocks patch
---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),
};

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