Re: GPMI iMX6ull timeout on DMA

Boris Brezillon
2019-08-12T07:31:59Z

On Mon, 12 Aug 2019 12:50:36 +1000
Greg Ungerer <gerg@kernel.org> wrote:

> Hi Boris,
>
> On 9/8/19 11:59 pm, Boris Brezillon wrote:
> > On Fri, 9 Aug 2019 23:57:08 +1000
> > Greg Ungerer <gerg@kernel.org> wrote:
> >> On 9/8/19 5:32 pm, Boris Brezillon wrote:
> >>> On Fri, 9 Aug 2019 16:55:22 +1000
> >>> Greg Ungerer <gerg@kernel.org> wrote:
> >>>> On 9/8/19 4:23 pm, Boris Brezillon wrote:
> >>>>> On Fri, 9 Aug 2019 15:20:52 +1000
> >>>>> Greg Ungerer <gerg@kernel.org> wrote:
> >>>>>> On 9/8/19 2:36 am, Boris Brezillon wrote:
> >>>>>>> On Mon, 5 Aug 2019 15:51:05 +1000
> >>>>>>> Greg Ungerer <gerg@kernel.org> wrote:
> >>>>>>>> On 2/8/19 10:51 pm, Boris Brezillon wrote:
> >>>>>>>>> On Fri, 2 Aug 2019 22:34:57 +1000
> >>>>>>>>> Greg Ungerer <gerg@kernel.org> wrote:
> >>>>>>>>>> On 31/7/19 4:28 pm, Boris Brezillon wrote:
> >>>>>>>>>>> On Wed, 31 Jul 2019 12:05:44 +1000
> >>>>>>>>>>> Greg Ungerer <gerg@kernel.org> wrote:
> >>>>>>>>>>>> On 30/7/19 6:38 pm, Miquel Raynal wrote:
> >>>>>>>>>>>>> Greg Ungerer <gerg@kernel.org> wrote on Tue, 30 Jul 2019 16:06:55 +1000:
> >>>>>>>>>>>>>> On 30/7/19 10:41 am, Greg Ungerer wrote:
> >>>>>>>>>>>>>>> On 30/7/19 10:28 am, Greg Ungerer wrote:
> >>>>>>>>>>>>>>>> On 29/7/19 10:47 pm, Miquel Raynal wrote:
> >>>>>>>>>>>>>>>>> Greg Ungerer <gerg@kernel.org> wrote on Mon, 29 Jul 2019 22:33:56 +1000:
> >>>>>>>>>>>>>>>>>> On 29/7/19 6:36 pm, Miquel Raynal wrote:
> >>>>>>>>>>>>>>>>>>> Greg Ungerer <gerg@kernel.org> wrote on Mon, 29 Jul 2019 16:41:51 +1000:
> >>>>>>>>>>>>>>> [snip]
> >>>>>>>>>>>> Note that this was generated on a normal boot up (not failure).
> >>>>>>>>>>>
> >>>>>>>>>>> The values looks good. Can you try with the below diff applied?
> >>>>>>>>>>> --->8---
> >>>>>>>>>>> diff --git a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
> >>>>>>>>>>> index 334fe3130285..9771f6a82abe 100644
> >>>>>>>>>>> --- a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
> >>>>>>>>>>> +++ b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
> >>>>>>>>>>> @@ -721,12 +721,10 @@ static void gpmi_nfc_apply_timings(struct gpmi_nand_data *this)
> >>>>>>>>>>> writel(hw->ctrl1n, gpmi_regs + HW_GPMI_CTRL1_SET);
> >>>>>>>>>>>
> >>>>>>>>>>> /* Wait 64 clock cycles before using the GPMI after enabling the DLL */
> >>>>>>>>>>> - dll_wait_time_us = USEC_PER_SEC / hw->clk_rate * 64;
> >>>>>>>>>>> - if (!dll_wait_time_us)
> >>>>>>>>>>> - dll_wait_time_us = 1;
> >>>>>>>>>>> + dll_wait_time_us = DIV_ROUND_UP(USEC_PER_SEC * 64, hw->clk_rate);
> >>>>>>>>>>>
> >>>>>>>>>>> /* Wait for the DLL to settle. */
> >>>>>>>>>>> - udelay(dll_wait_time_us);
> >>>>>>>>>>> + usleep_range(dll_wait_time_us, dll_wait_time_us * 10);
> >>>>>>>>>>> }
> >>>>>>>>>>>
> >>>>>>>>>>> static int gpmi_setup_data_interface(struct nand_chip *chip, int chipnr,
> >>>>>>>>>>
> >>>>>>>>>> Eventually it failed, in the same way with with same errors.
> >>>>>>>>>> Took quite a while, over 600 boot cycles.
> >>>>>>>>>>
> >>>>>>>>>> Note also that I had to hand merge the changes, since in 5.1.14 that
> >>>>>>>>>> gpmi_nfc_apply_timings() is in gpmi-lib.c. But it was trivial to do.
> >>>>>>>>>
> >>>>>>>>> Oh well. I guess the next thing to do would be to dump the timing regs
> >>>>>>>>> and clk rate that are set by the bootloader (before the driver override
> >>>>>>>>> them) or those applied by an older kernel (one that didn't have that
> >>>>>>>>> issue).
> >>>>>>>>
> >>>>>>>> Is this useful?
> >>>>>>>
> >>>>>>> Hm, looks like it's configured in mode 0, so no, it's not super useful.
> >>>>>>> Can you try booting an older kernel (one that didn't have the
> >>>>>>> ->setup_data_interface() hook implemented).
> >>>>>>
> >>>>>> Ok. I went back from 5.1 and the first kernel I could find that
> >>>>>> returned no grep hits for "setup_data_interface" was 4.16.
> >>>>>>
> >>>>>> So I built for my target with that and added similar trace to dump
> >>>>>> the hardware register settings for that. Debug output looks like
> >>>>>> this now for it:
> >>>>>>
> >>>>>> ...
> >>>>>> drivers/mtd/nand/gpmi-nand/gpmi-nand.c(807): gpmi_get_clks()
> >>>>>> clk_get_rate(r->clock[0])=22000000
> >>>>>> drivers/mtd/nand/gpmi-nand/gpmi-lib.c(1054): gpmi_begin()
> >>>>>> HW_GPMI_TIMING0=0x00010203
> >>>>>> HW_GPMI_TIMING1=0x05000000
> >>>>>> nand: device found, Manufacturer ID: 0x2c, Chip ID: 0xda
> >>>>>> nand: Micron MT29F2G08ABAEAWP
> >>>>>> nand: 256 MiB, SLC, erase size: 128 KiB, page size: 2048, OOB size: 64
> >>>>>> drivers/mtd/nand/gpmi-nand/gpmi-lib.c(966): enable_edo_mode()
> >>>>>> clk_get_rate(r->clock[0])=99000000
> >>>>>> gpmi-nand 1806000.gpmi-nand: enable the asynchronous EDO mode 5
> >>>>>> drivers/mtd/nand/gpmi-nand/gpmi-lib.c(1054): gpmi_begin()
> >>>>>> HW_GPMI_TIMING0=0x00010101
> >>>>>
> >>>>> TIMING0 match the one you have with 5.1 kernels.
> >>>>>
> >>>>>> HW_GPMI_TIMING1=0x90000000
> >>>>>
> >>>>> And we even have a bigger timeout value in 5.1 (0xe0000000), so we
> >>>>> should be all safe WRT to timings in TIMING{0,1}.
> >>>>>
> >>>>> Can you dump CTRL1?
> >>>>
> >>>> drivers/mtd/nand/gpmi-nand/gpmi-lib.c(1054): gpmi_begin()
> >>>> HW_GPMI_TIMING0=0x00010101
> >>>> HW_GPMI_TIMING1=0x90000000
> >>>> HW_GPMI_CTRL1_SET=0x01c4800c
> >>>
> >>> The read/write delay fields seem to match, but there are a few more
> >>> fields set in this version:
> >>> - DECOUPLE_CS
> >>> - BCH_MODE
> >>> - DEV_RESET
> >>> - CTRL1_ATA_IRQRDY_POLARITY__ACTIVEHIGH
> >>>
> >>> Looks like those fields are not explicitly set in the gpmi_begin()
> >>> patch, but maybe you dumped CTRL1. Would you mind sharing your patch?
> >>
> >> Attached.
> >
> > Hm, you should read CTRL1 instead of CTRL1_SET which I guess is WO.
>
>
> Here is 2 sets of trace dumping the same set of registers.
> This first is on the linux-4.16 kernel:
>
> Linux version 4.16.0 (gerg@goober) (gcc version 4.8.3 (GCC)) #9 Mon Aug 12 10:46:25 AEST 2019
> ...
> nand: device found, Manufacturer ID: 0x2c, Chip ID: 0xda
> nand: Micron MT29F2G08ABAEAWP
> nand: 256 MiB, SLC, erase size: 128 KiB, page size: 2048, OOB size: 64
> gpmi-nand 1806000.gpmi-nand: use legacy bch geometry
> gpmi-nand 1806000.gpmi-nand: enable the asynchronous EDO mode 5
> drivers/mtd/nand/gpmi-nand/gpmi-lib.c(1110): gpmi_begin()
> HW_GPMI_TIMING0=0x00010101
> HW_GPMI_TIMING1=0x90000000
> HW_GPMI_CTRL1=0x01c6800c
> r->clock[0]=99000000
> Scanning device for bad blocks
> 5 ofpart partitions found on MTD device gpmi-nand
> Creating 5 MTD partitions on "gpmi-nand":
> 0x000000000000-0x000000500000 : "u-boot"
> 0x000000500000-0x000000600000 : "u-boot-env"
> 0x000000600000-0x000000800000 : "log"
> 0x000000800000-0x000010000000 : "flash"
> 0x000000000000-0x000010000000 : "all"
> gpmi-nand 1806000.gpmi-nand: driver registered.
> ...
>
>
> And then this is from the 5.1.14 kernel:
>
> Linux version 5.1.14 (gerg@goober) (gcc version 4.8.3 (GCC)) #25 Mon Aug 12 10:49:21 AEST 2019
> ...
> nand: device found, Manufacturer ID: 0x2c, Chip ID: 0xda
> nand: Micron MT29F2G08ABAEAWP
> nand: 256 MiB, SLC, erase size: 128 KiB, page size: 2048, OOB size: 64
> drivers/mtd/nand/raw/gpmi-nand/gpmi-lib.c(510): gpmi_nfc_apply_timings()
> HW_GPMI_TIMING0=0x00020101
> HW_GPMI_TIMING1=0xb0000000
> HW_GPMI_CTRL1=0x0104000c
> r->clock[0]=22000000
> drivers/mtd/nand/raw/gpmi-nand/gpmi-lib.c(510): gpmi_nfc_apply_timings()
> HW_GPMI_TIMING0=0x00010101
> HW_GPMI_TIMING1=0xe0000000
> HW_GPMI_CTRL1=0x01c6800c
> r->clock[0]=99000000
> Scanning device for bad blocks
> 5 fixed-partitions partitions found on MTD device gpmi-nand
> Creating 5 MTD partitions on "gpmi-nand":
> 0x000000000000-0x000000500000 : "u-boot"
> 0x000000500000-0x000000600000 : "u-boot-env"
> 0x000000600000-0x000000800000 : "log"
> 0x000000800000-0x000010000000 : "flash"
> 0x000000000000-0x000010000000 : "all"
> gpmi-nand 1806000.gpmi-nand: driver registered.
>
>
> Register settings read back from the registers themselves at the end
> of the respective setting routines (so gpmi_begin() for 4.16 and
> gpmi_nfc_apply_timings() for 5.1.14)

Hm, CTRL1 is identical. Can you dump all regs at the beginning and at
the end of those funcs?