Re: [PATCH 1/3] ata: sata_dwc_460ex: use "dmas" DT property to find dma channel

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

On Fri, 2015-12-18 at 08:33 -0400, Julian Margetson wrote:
> On 12/18/2015 8:04 AM, Måns Rullgård wrote:
> > Julian Margetson <runaway@candw.ms> writes:
> > 
> > > On 12/17/2015 8:06 PM, Måns Rullgård wrote:
> > > > Julian Margetson <runaway@candw.ms> writes:
> > > > 
> > > > > On 12/17/2015 3:53 PM, Måns Rullgård wrote:
> > > > > > Julian Margetson <runaway@candw.ms> writes:
> > > > > > 
> > > > > > > On 12/17/2015 2:51 PM, Måns Rullgård wrote:
> > > > > > > > Julian Margetson <runaway@candw.ms> writes:
> > > > > > > > 
> > > > > > > > > On 12/17/2015 1:59 PM, Måns Rullgård wrote:
> > > > > > > > > > Julian Margetson <runaway@candw.ms> writes:
> > > > > > > > > > 
> > > > > > > > > > > I have been running my machine mostly configured
> > > > > > > > > > > for pciex1  thus with
> > > > > > > > > > > the sata_dwc disabled.
> > > > > > > > > > > The changes to sata_dwc-460ex do cause an oops.
> > > > > > > > > > > I will try to give more detailed info over this
> > > > > > > > > > > weekend .
> > > > > > > > > > The driver as is upstream would do that since it
> > > > > > > > > > unconditionally
> > > > > > > > > > dereferences a null pointer in the probe
> > > > > > > > > > function.  My patch fixes that
> > > > > > > > > > as a side-effect.
> > > > > > > > > > 
> > > > > > > > > patching file drivers/ata/Kconfig
> > > > > > > > > 
> > > > > > > > > Hunk #1 FAILED at 296.
> > > > > > > > [...]
> > > > > > > > 
> > > > > > > > > root@julian-VirtualBox:/usr/src/linux-3.18.25#
> > > > > > > > The patch is against 4.4-rc5.
> > > > > > > > 
> > > > > > >     CC      drivers/ata/sata_dwc_460ex.o
> > > > > > > 
> > > > > > > drivers/ata/sata_dwc_460ex.c:198:15: error: variable
> > > > > > > ‘sata_dwc_dma_dws’ has initializer but incomplete
> > > > > > > type
> > > > > > > 
> > > > > > >     static struct dw_dma_slave sata_dwc_dma_dws = {
> > > > > > >                   ^
> > > > > > It builds, albeit with an unrelated warning, using the
> > > > > > attached config.
> > > > > > Maybe there's a missing config dependency somewhere.
> > > > > > 
> > > > > I am attempting to cross compile under Ubuntu 14.04 X86 in
> > > > > Virtualbox
> > > > > with your .config.
> > > > > 4.4.0-rc5 builds ok with no patches applied .
> > > > > Once your patch is applied it fails to build .
> > > > > 
> > > > > CC      drivers/ata/sata_dwc_460ex.o
> > > > > drivers/ata/sata_dwc_460ex.c:198:15: error: variable
> > > > > ‘sata_dwc_dma_dws’ has initializer but incomplete type
> > > > >    static struct dw_dma_slave sata_dwc_dma_dws = {
> > > > >                  ^
> > > > Bizarre.  This is what it looks like here:
> > > > 
> > > > mru@unicorn:/tmp/linux-sata$ git status
> > > > On branch sata-dwc
> > > > nothing to commit, working directory clean
> > > > mru@unicorn:/tmp/linux-sata$ git describe
> > > > v4.4-rc5
> > > > mru@unicorn:/tmp/linux-sata$ sha1sum /tmp/0001-ata-
> > > > sata_dwc_460ex-use-dmas-DT-property-to-find-dma-.patch
> > > > e300971aa483390f82de2e9120dc16e460e74feb  /tmp/0001-ata-
> > > > sata_dwc_460ex-use-dmas-DT-property-to-find-dma-.patch
> > > > mru@unicorn:/tmp/linux-sata$ git am /tmp/0001-ata-
> > > > sata_dwc_460ex-use-dmas-DT-property-to-find-dma-.patch
> > > > Applying: ata: sata_dwc_460ex: use "dmas" DT property to find
> > > > dma channel
> > > > mru@unicorn:/tmp/linux-sata$ sha1sum .config
> > > > 4e7615b8d2fa9a1c4b4ae9ffc363aefcaf3789ca  .config
> > > > mru@unicorn:/tmp/linux-sata$ make ARCH=powerpc
> > > > CROSS_COMPILE=powerpc64-none-linux-gnu- oldconfig
> > > >     HOSTCC  scripts/basic/fixdep
> > > >     HOSTCC  scripts/kconfig/conf.o
> > > >     SHIPPED scripts/kconfig/zconf.tab.c
> > > >     SHIPPED scripts/kconfig/zconf.lex.c
> > > >     SHIPPED scripts/kconfig/zconf.hash.c
> > > >     HOSTCC  scripts/kconfig/zconf.tab.o
> > > >     HOSTLD  scripts/kconfig/conf
> > > > scripts/kconfig/conf  --oldconfig Kconfig
> > > > #
> > > > # configuration written to .config
> > > > #
> > > > mru@unicorn:/tmp/linux-sata$ make ARCH=powerpc
> > > > CROSS_COMPILE=powerpc64-none-linux-gnu-
> > > > drivers/ata/sata_dwc_460ex.o
> > > > scripts/kconfig/conf  --silentoldconfig Kconfig
> > > >     CHK     include/config/kernel.release
> > > >     UPD     include/config/kernel.release
> > > >     WRAP    arch/powerpc/include/generated/asm/clkdev.h
> > > >     WRAP    arch/powerpc/include/generated/asm/div64.h
> > > >     WRAP    arch/powerpc/include/generated/asm/irq_regs.h
> > > >     WRAP    arch/powerpc/include/generated/asm/irq_work.h
> > > >     WRAP    arch/powerpc/include/generated/asm/local64.h
> > > >     WRAP    arch/powerpc/include/generated/asm/mcs_spinlock.h
> > > >     WRAP    arch/powerpc/include/generated/asm/preempt.h
> > > >     WRAP    arch/powerpc/include/generated/asm/rwsem.h
> > > >     WRAP    arch/powerpc/include/generated/asm/vtime.h
> > > >     CHK     include/generated/uapi/linux/version.h
> > > >     UPD     include/generated/uapi/linux/version.h
> > > >     CHK     include/generated/utsrelease.h
> > > >     UPD     include/generated/utsrelease.h
> > > >     CC      kernel/bounds.s
> > > >     CHK     include/generated/bounds.h
> > > >     UPD     include/generated/bounds.h
> > > >     CHK     include/generated/timeconst.h
> > > >     UPD     include/generated/timeconst.h
> > > >     CC      arch/powerpc/kernel/asm-offsets.s
> > > >     CHK     include/generated/asm-offsets.h
> > > >     UPD     include/generated/asm-offsets.h
> > > >     CALL    scripts/checksyscalls.sh
> > > >     HOSTCC  scripts/dtc/dtc.o
> > > >     HOSTCC  scripts/dtc/flattree.o
> > > >     HOSTCC  scripts/dtc/fstree.o
> > > >     HOSTCC  scripts/dtc/data.o
> > > >     HOSTCC  scripts/dtc/livetree.o
> > > >     HOSTCC  scripts/dtc/treesource.o
> > > >     HOSTCC  scripts/dtc/srcpos.o
> > > >     HOSTCC  scripts/dtc/checks.o
> > > >     HOSTCC  scripts/dtc/util.o
> > > >     SHIPPED scripts/dtc/dtc-lexer.lex.c
> > > >     SHIPPED scripts/dtc/dtc-parser.tab.h
> > > >     HOSTCC  scripts/dtc/dtc-lexer.lex.o
> > > >     SHIPPED scripts/dtc/dtc-parser.tab.c
> > > >     HOSTCC  scripts/dtc/dtc-parser.tab.o
> > > >     HOSTLD  scripts/dtc/dtc
> > > >     CC      scripts/mod/empty.o
> > > >     HOSTCC  scripts/mod/mk_elfconfig
> > > >     MKELF   scripts/mod/elfconfig.h
> > > >     HOSTCC  scripts/mod/modpost.o
> > > >     CC      scripts/mod/devicetable-offsets.s
> > > >     GEN     scripts/mod/devicetable-offsets.h
> > > >     HOSTCC  scripts/mod/file2alias.o
> > > >     HOSTCC  scripts/mod/sumversion.o
> > > >     HOSTLD  scripts/mod/modpost
> > > >     HOSTCC  scripts/kallsyms
> > > >     CC      drivers/ata/sata_dwc_460ex.o
> > > > drivers/ata/sata_dwc_460ex.c: In function 'dma_dwc_xfer_setup':
> > > > drivers/ata/sata_dwc_460ex.c:383:20: warning: cast from pointer
> > > > to integer of different size [-Wpointer-to-int-cast]
> > > >     dma_addr_t addr = (dma_addr_t)&hsdev->sata_dwc_regs->dmadr;
> > > >                       ^
> > > > mru@unicorn:/tmp/linux-sata$
> > > > 
> > > > Patch file and .config attached.
> > > > 
> > > > Looking into that warning, I doubt it works as is, but that's
> > > > not caused
> > > > by my patch.  I can try to come up with a fix, but again, I
> > > > can't test it.
> > > > 
> > > Builds now. Using my own .config.
> > What changed?
> I may have messed up the patch initially .
> > 
> > > [    4.784199] sata-dwc 4bffd1000.sata: id 0, controller version
> > > 1.82
> > > [    4.791186] scsi host0: sata-dwc
> > > [    4.794830] ata1: SATA max UDMA/133 irq 36
> > > [    4.799463] sata_sil 0001:00:04.0: Applying R_ERR on DMA
> > > activate FIS errata fix
> > > [    4.807959] scsi host1: sata_sil
> > > [    4.811662] scsi host2: sata_sil
> > > [    4.815242] ata2: SATA max UDMA/100 mmio m512@0xd84280000 tf
> > > 0xd84280080 irq 21
> > > [    4.822990] ata3: SATA max UDMA/100 mmio m512@0xd84280000 tf
> > > 0xd842800c0 irq 21
> > > 
> > > [    5.143502] ata1: SATA link up 3.0 Gbps (SStatus 123 SControl
> > > 300)
> > > [    5.164367] ata2: SATA link up 1.5 Gbps (SStatus 113 SControl
> > > 310)
> > > [    5.185174] ppc-of-ohci 4bffd0000.usb: irq 32, io mem
> > > 0x4bffd0000
> > > [    5.206125] Unable to handle kernel paging request for data at
> > > address 0x00000000
> > > [    5.228546] Faulting instruction address: 0xc043a2c8
> > > [    5.248577] Vector: 300 (Data Access) at [eddafae0]
> > > [    5.268658]     pc: c043a2c8: sata_dwc_qc_issue+0xb8/0x204
> > Well, that's not good.  Can you translate that address to a line of
> > code?
> > 
> need some guidance on method .

Your toolchain has to have addr2line binary. It does a job if you
compile kernel with enough debug information (you may try to use make
CONFIG_DEBUG_INFO=y IIRC and then your specific addr2line binary).


-- 
Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Intel Finland Oy