Hi Bjorn, Thanks a lot for your comments! > -----Original Message----- > From: Bjorn Helgaas [mailto:helgaas@xxxxxxxxxx] > Sent: 2019年3月11日 22:14 > To: Z.q. Hou <zhiqiang.hou@xxxxxxx> > Cc: linux-pci@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; > devicetree@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; > robh+dt@xxxxxxxxxx; mark.rutland@xxxxxxx; l.subrahmanya@xxxxxxxxxxxxxx; > shawnguo@xxxxxxxxxx; Leo Li <leoyang.li@xxxxxxx>; > lorenzo.pieralisi@xxxxxxx; catalin.marinas@xxxxxxx; > will.deacon@xxxxxxx; Mingkai Hu <mingkai.hu@xxxxxxx>; M.h. Lian > <minghuan.lian@xxxxxxx>; Xiaowei Bao <xiaowei.bao@xxxxxxx> > Subject: Re: [PATCHv4 11/28] PCI: mobiveil: only fix up the Class Code field > > On Mon, Mar 11, 2019 at 09:31:23AM +0000, Z.q. Hou wrote: > > From: Hou Zhiqiang <Zhiqiang.Hou@xxxxxxx> > > > > Fix up the Class Code to PCI bridge, do not change the Revision ID. > > And move the fixup to mobiveil_host_init function. > > Add parens after function name. > > Please explain why this change is needed. Does it fix a bug? > > Does this fix the problem that the PCI core didn't correctly identify the device > as a bridge because it identified bridges by class code instead of header type? > > That problem *should* be fixed by b2fb5cc57469 ("PCI: Rely on config space > header type, not class code"), which is now upstream. > > You might still want this class code change so that lspci shows the correct > thing. That's fine, but the changelog should say why we're doing it. > Subrahmanya's original patch is to fixup 'Class Code' field, but it also fixed the 'Revision ID' field. This patch is patch is to remove the fixup of 'Revision ID' field. > > Fixes: 9af6bcb11e12 ("PCI: mobiveil: Add Mobiveil PCIe Host Bridge IP > > driver") > > Make this "Fixes:" line a single line again. > > > Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@xxxxxxx> > > Reviewed-by: Minghuan Lian <Minghuan.Lian@xxxxxxx> > > Reviewed-by: Subrahmanya Lingappa <l.subrahmanya@xxxxxxxxxxxxxx> > > --- > > V4: > > - no change > > > > drivers/pci/controller/pcie-mobiveil.c | 9 ++++++--- > > 1 file changed, 6 insertions(+), 3 deletions(-) > > > > diff --git a/drivers/pci/controller/pcie-mobiveil.c > > b/drivers/pci/controller/pcie-mobiveil.c > > index 78e575e71f4d..8eee1ab7ee24 100644 > > --- a/drivers/pci/controller/pcie-mobiveil.c > > +++ b/drivers/pci/controller/pcie-mobiveil.c > > @@ -653,6 +653,12 @@ static int mobiveil_host_init(struct mobiveil_pcie > *pcie) > > type, resource_size(win->res)); > > } > > > > + /* fixup for PCIe class register */ > > + value = csr_readl(pcie, PAB_INTP_AXI_PIO_CLASS); > > + value &= 0xff; > > + value |= (PCI_CLASS_BRIDGE_PCI << 16); > > + csr_writel(pcie, value, PAB_INTP_AXI_PIO_CLASS); > > + > > /* setup MSI hardware registers */ > > mobiveil_pcie_enable_msi(pcie); > > > > @@ -896,9 +902,6 @@ static int mobiveil_pcie_probe(struct > platform_device *pdev) > > goto error; > > } > > > > - /* fixup for PCIe class register */ > > - csr_writel(pcie, 0x060402ab, PAB_INTP_AXI_PIO_CLASS); > > - > > /* initialize the IRQ domains */ > > ret = mobiveil_pcie_init_irq_domain(pcie); > > if (ret) { > > -- > > 2.17.1 > > Thanks, Zhiqiang
