On 07/13/2018 12:09 PM, Masahiro Yamada wrote: > Hi Marek > > 2018-07-13 17:56 GMT+09:00 Marek Vasut <ma...@denx.de>: >> On 07/13/2018 10:23 AM, Masahiro Yamada wrote: >>> Hi Marek, >>> >>> 2018-07-13 16:59 GMT+09:00 Marek Vasut <ma...@denx.de>: >>>> On 07/13/2018 07:13 AM, Masahiro Yamada wrote: >>>>> 2018-07-12 21:51 GMT+09:00 Marek Vasut <ma...@denx.de>: >>>>>> On 06/20/2018 09:14 AM, Masahiro Yamada wrote: >>>>>>> Hi Marek, >>>>>> >>>>>> Hi! >>>>>> >>>>>>> 2018-06-20 13:43 GMT+09:00 Marek Vasut <ma...@denx.de>: >>>>>>>> On 06/19/2018 08:39 AM, Masahiro Yamada wrote: >>>>>>>>> Hi Marek, >>>>>>>> >>>>>>>> Hi, >>>>>>>> >>>>>>>>> 2018-06-08 5:17 GMT+09:00 Marek Vasut <ma...@denx.de>: >>>>>>>>>> Replace the ad-hoc DMA cache management functions with common >>>>>>>>>> bouncebuf, >>>>>>>>>> since those functions are not handling cases where unaligned buffer >>>>>>>>>> is >>>>>>>>>> passed in, >>>>>>>>> >>>>>>>>> >>>>>>>>> Were you hit by a problem, >>>>>>>>> or just-in-case replacement? >>>>>>>> >>>>>>>> Yes, UBI triggers unaligned cache operations on my system (SoCFPGA). >>>>>>>>> I thought I took care of the buffer alignment. >>>>>>>>> >>>>>>>>> The bounce buffer is allocated by kmalloc(): >>>>>>>>> https://github.com/u-boot/u-boot/blob/v2018.05/drivers/mtd/nand/denali.c#L1348 >>>>>>>>> >>>>>>>>> According to the lib/linux_compat.c implementation, >>>>>>>>> it returns memory aligned with ARCH_DMA_MINALIGN. >>>>>>>>> >>>>>>>>> >>>>>>>>> If the buffer is passed from the upper MTD layer, >>>>>>>>> the NAND core also makes sure the enough alignment: >>>>>>>>> https://github.com/u-boot/u-boot/blob/v2018.05/drivers/mtd/nand/denali.c#L1273 >>>>>>>>> >>>>>>>>> This is how this driver works in Linux. >>>>>>>>> >>>>>>>>> I'd rather want to keep the current code >>>>>>>>> unless this is a real problem, >>>>>>>>> >>>>>>>>> >>>>>>>>> One possible clean-up is to move dma_(un)map_single to a common place. >>>>>>>> Is there any chance you can try UBI on the denali nand on uniphier ? :) >>>>>>> >>>>>>> >>>>>>> I tested the driver only for raw block devices. >>>>>>> >>>>>>> OK, I will test UBI on my platform. >>>>>>> >>>>>>> BTW, do you see the problem only in U-Boot? >>>>>>> Is the denali driver in Linux working fine? >>>>>> >>>>>> Bump on this one ? >>>>>> >>>>> >>>>> Sorry for delay. >>>>> >>>>> >>>>> UBI is working for me without your patch. >>>>> >>>>> Not sure what is the difference. >>>>> >>>>> I will dig into it a little more, though. >>>> >>>> Verify that you're not seeing any unaligned cache flushes. I do. >>> >>> >>> Yeah, I am testing it now, >>> but I never see 'Misaligned operation at range' when using UBI. >>> >>> However, I found a simple way to trigger the warning >>> in raw device access. >>> >>> >>> >>> => nand read 81000010 0 1000 >>> >>> NAND read: device 0 offset 0x0, size 0x1000 >>> CACHE: Misaligned operation at range [81000010, 81001010] >>> CACHE: Misaligned operation at range [81000010, 81001010] >>> CACHE: Misaligned operation at range [81000010, 81001010] >>> CACHE: Misaligned operation at range [81000010, 81001010] >>> 4096 bytes read: OK >>> >>> >>> >>> >>> I can fix it with one liner. >>> >>> >>> >>> diff --git a/drivers/mtd/nand/denali.c b/drivers/mtd/nand/denali.c >>> index 6266c8a..f391727 100644 >>> --- a/drivers/mtd/nand/denali.c >>> +++ b/drivers/mtd/nand/denali.c >>> @@ -1270,7 +1270,7 @@ int denali_init(struct denali_nand_info *denali) >>> denali->dma_avail = 1; >>> >>> if (denali->dma_avail) { >>> - chip->buf_align = 16; >>> + chip->buf_align = ARCH_DMA_MINALIGN; >>> if (denali->caps & DENALI_CAP_DMA_64BIT) >>> denali->setup_dma = denali_setup_dma64; >>> else >>> >>> >>> I guess this will work for you too. >> >> Doesn't that only apply if DMA is available ? > > Of course. > If you use PIO instead of DMA, > you do not need to perform cache operation, right? > > > >> And anyway, I'd rather use common U-Boot code than have a custom >> implementation in a driver which we need to maintain and fix separately. > > > bounce_buffer_{start,stop} does > malloc() and free() every time. > This is not efficient. > > > struct nand_chip already contains page buffers, > which guarantee alignment for DMA. > > https://github.com/u-boot/u-boot/blob/v2018.07/include/linux/mtd/rawnand.h#L640 > > > We can rely on the NAND framework > for handling DMA-capable alignment.
Clearly that doesn't work, otherwise I won't need this bounce buffer patch ? -- Best regards, Marek Vasut _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
