> -----Original Message----- > From: Wood Scott-B07421 > Sent: Wednesday, March 20, 2013 12:32 AM > To: Jia Hongtao-B38951 > Cc: Kumar Gala; linuxppc-dev@lists.ozlabs.org; Wood Scott-B07421; > mich...@ellerman.id.au; Li Yang-R58472 > Subject: Re: [PATCH V2] powerpc/85xx: workaround for chips with MSI > hardware errata > > ;On 03/19/2013 03:03:13 AM, Jia Hongtao-B38951 wrote: > > > > > > > -----Original Message----- > > > From: Kumar Gala [mailto:ga...@kernel.crashing.org] > > > Sent: Friday, March 15, 2013 11:53 PM > > > To: Jia Hongtao-B38951 > > > Cc: linuxppc-dev@lists.ozlabs.org; Wood Scott-B07421; > > > mich...@ellerman.id.au; Li Yang-R58472 > > > Subject: Re: [PATCH V2] powerpc/85xx: workaround for chips with MSI > > > hardware errata > > > > > > > > > On Mar 14, 2013, at 9:00 PM, Jia Hongtao-B38951 wrote: > > > > > > > > > > > > > > >> -----Original Message----- > > > >> From: Kumar Gala [mailto:ga...@kernel.crashing.org] > > > >> Sent: Friday, March 15, 2013 4:05 AM > > > >> To: Jia Hongtao-B38951 > > > >> Cc: linuxppc-dev@lists.ozlabs.org; Wood Scott-B07421; > > > >> mich...@ellerman.id.au; Li Yang-R58472; Jia Hongtao-B38951 > > > >> Subject: Re: [PATCH V2] powerpc/85xx: workaround for chips with > > MSI > > > >> hardware errata > > > >> > > > >> > > > >> On Mar 14, 2013, at 5:35 AM, Jia Hongtao wrote: > > > >> > > > >>> The MPIC version 2.0 has a MSI errata (errata PIC1 of mpc8544), > > It > > > >>> causes that neither MSI nor MSI-X can work fine. This is a > > > >>> workaround to allow MSI-X to function properly. > > > >>> > > > >>> Signed-off-by: Liu Shuo <soniccat....@gmail.com> > > > >>> Signed-off-by: Li Yang <le...@freescale.com> > > > >>> Signed-off-by: Jia Hongtao <hongtao....@freescale.com> > > > >>> --- > > > >>> Changes for V2: > > > >>> - Address almost all the comments from Michael Ellerman for V1. > > > >>> Here is the link: > > > >>> http://patchwork.ozlabs.org/patch/226833/ > > > >>> > > > >>> arch/powerpc/sysdev/fsl_msi.c | 65 > > > >>> +++++++++++++++++++++++++++++++++++++++++-- > > > >>> arch/powerpc/sysdev/fsl_msi.h | 2 ++ > > > >>> 2 files changed, 64 insertions(+), 3 deletions(-) > > > >>> > > > >>> diff --git a/arch/powerpc/sysdev/fsl_msi.c > > > >>> b/arch/powerpc/sysdev/fsl_msi.c index 178c994..54cb83e 100644 > > > >>> --- a/arch/powerpc/sysdev/fsl_msi.c > > > >>> +++ b/arch/powerpc/sysdev/fsl_msi.c > > > >>> @@ -98,8 +98,18 @@ static int fsl_msi_init_allocator(struct > > fsl_msi > > > >>> *msi_data) > > > >>> > > > >>> static int fsl_msi_check_device(struct pci_dev *pdev, int nvec, > > int > > > >>> type) { > > > >>> - if (type == PCI_CAP_ID_MSIX) > > > >>> - pr_debug("fslmsi: MSI-X untested, trying > > anyway.\n"); > > > >>> + struct fsl_msi *msi; > > > >>> + > > > >>> + if (type == PCI_CAP_ID_MSI) { > > > >>> + /* > > > >>> + * MPIC version 2.0 has erratum PIC1. For now > > MSI > > > >>> + * could not work. So check to prevent MSI from > > > >>> + * being used on the board with this erratum. > > > >>> + */ > > > >>> + list_for_each_entry(msi, &msi_head, list) > > > >>> + if (msi->feature & MSI_HW_ERRATA_ENDIAN) > > > >>> + return -EINVAL; > > > >>> + } > > > >>> > > > >>> return 0; > > > >>> } > > > >>> @@ -142,7 +152,17 @@ static void fsl_compose_msi_msg(struct > > pci_dev > > > >> *pdev, int hwirq, > > > >>> msg->address_lo = lower_32_bits(address); > > > >>> msg->address_hi = upper_32_bits(address); > > > >>> > > > >>> - msg->data = hwirq; > > > >>> + /* > > > >>> + * MPIC version 2.0 has erratum PIC1. It causes > > > >>> + * that neither MSI nor MSI-X can work fine. > > > >>> + * This is a workaround to allow MSI-X to function > > > >>> + * properly. It only works for MSI-X, we prevent > > > >>> + * MSI on buggy chips in fsl_msi_check_device(). > > > >>> + */ > > > >>> + if (msi_data->feature & MSI_HW_ERRATA_ENDIAN) > > > >>> + msg->data = __swab32(hwirq); > > > >>> + else > > > >>> + msg->data = hwirq; > > > >>> > > > >>> pr_debug("%s: allocated srs: %d, ibs: %d\n", > > > >>> __func__, hwirq / IRQS_PER_MSI_REG, hwirq % > > IRQS_PER_MSI_REG); > > > >> @@ > > > >>> -361,6 +381,35 @@ static int fsl_msi_setup_hwirq(struct fsl_msi > > > >>> *msi, > > > >> struct platform_device *dev, > > > >>> return 0; > > > >>> } > > > >>> > > > >>> +/* MPIC version 2.0 has erratum PIC1 */ static int > > > >>> +mpic_has_errata(struct platform_device *dev) { > > > >>> + struct device_node *mpic_node; > > > >>> + > > > >>> + mpic_node = of_irq_find_parent(dev->dev.of_node); > > > >>> + if (mpic_node) { > > > >>> + u32 *reg_base, brr1 = 0; > > > >>> + /* Get the PIC reg base */ > > > >>> + reg_base = of_iomap(mpic_node, 0); > > > >>> + of_node_put(mpic_node); > > > >>> + if (!reg_base) { > > > >>> + dev_err(&dev->dev, "ioremap problem > > failed.\n"); > > > >>> + return -EIO; > > > >>> + } > > > >>> + > > > >>> + /* Get the mpic version from block revision > > register 1 */ > > > >>> + brr1 = in_be32(reg_base + MPIC_FSL_BRR1); > > > >>> + iounmap(reg_base); > > > >>> + if ((brr1 & MPIC_FSL_BRR1_VER) == 0x0200) > > > >>> + return 1; > > > >>> + } else { > > > >>> + dev_err(&dev->dev, "MSI can't find his parent > > mpic node.\n"); > > > >>> + return -ENODEV; > > > >>> + } > > > >>> + > > > >>> + return 0; > > > >>> +} > > > >>> + > > > >>> static const struct of_device_id fsl_of_msi_ids[]; static int > > > >>> fsl_of_msi_probe(struct platform_device *dev) { @@ -423,6 > > +472,16 @@ > > > >>> static int fsl_of_msi_probe(struct platform_device *dev) > > > >>> > > > >>> msi->feature = features->fsl_pic_ip; > > > >>> > > > >>> + if ((features->fsl_pic_ip & FSL_PIC_IP_MASK) == > > FSL_PIC_IP_MPIC) { > > > >>> + rc = mpic_has_errata(dev); > > > >>> + if (rc > 0) { > > > >>> + msi->feature |= MSI_HW_ERRATA_ENDIAN; > > > >>> + } else if (rc < 0) { > > > >>> + err = rc; > > > >>> + goto error_out; > > > >>> + } > > > >>> + } > > > >>> + > > > >>> /* > > > >>> * Remember the phandle, so that we can match with any > > PCI nodes > > > >>> * that have an "fsl,msi" property. > > > >>> diff --git a/arch/powerpc/sysdev/fsl_msi.h > > > >>> b/arch/powerpc/sysdev/fsl_msi.h index 8225f86..7389e8e 100644 > > > >>> --- a/arch/powerpc/sysdev/fsl_msi.h > > > >>> +++ b/arch/powerpc/sysdev/fsl_msi.h > > > >>> @@ -25,6 +25,8 @@ > > > >>> #define FSL_PIC_IP_IPIC 0x00000002 > > > >>> #define FSL_PIC_IP_VMPIC 0x00000003 > > > >>> > > > >>> +#define MSI_HW_ERRATA_ENDIAN 0x00000010 > > > >>> + > > > >> > > > >> Is there any reason to put this in fsl_msi.h rather than just in > > > >> fsl_msi.c itself? > > > >> > > > >> - k > > > > > > > > Actually no. This micro is only used by fsl_msi.c. > > > > Will move it to fsl_msi.c. > > > > > > > > Thanks. > > > > -Hongtao. > > > > > > Also, wondering if we can do the mpic version detection in mpic.c > > and not > > > here. I'm not sure what means we'd have to get back to the mpic > > struct > > > so we could possible use mpic->flags. > > > > > > > Use the MPIC version result in mpic.c was my plan. > > But as you point out there seems no obvious way to get the mpic > > struct. > > mpic struct is defined as an automatic variable in platform files. > > Also MSI driver is not so close to mpic driver under current > > architecture. > > > > If you get some elegant way to do this please feel free to tell me. > > Declare a non-static function to retrieve the MPIC version. > > -Scott
The struct pointer "mpic" is for internal use only while the "mpic_primary" could be used for external. So I'd like to declare two functions something like: mpic_get_version(struct *mpic); mpic_primary_get_version(void); The first function is for mpic.c internal use by mpic_alloc() and mpic_init(). The second function is for external use by fsl_msi.c. There will be two patches: 1. Declare the two MPIC get-version APIs. 2. Fix the MSI errata. Any comments for this plan? Thanks. -Hongtao. _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
