| Message ID | 20151102210650.GA17552@localhost (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Bjorn, I am so sorry about text code setting. Now, I carefully checked the mail configuration again, hope it is ok. I greatly appreciate your review and comments. Thanks, Minghuan > -----Original Message----- > From: Bjorn Helgaas [mailto:helgaas@kernel.org] > Sent: Tuesday, November 03, 2015 5:07 AM > To: Lian Minghuan-B31939 <Minghuan.Lian@freescale.com> > Cc: linux-pci@vger.kernel.org; linux-arm-kernel@lists.infradead.org; Zang > Roy-R61911 <tie-fei.zang@freescale.com>; Hu Mingkai-B21284 > <Mingkai.Hu@freescale.com>; Yoder Stuart-B08248 > <stuart.yoder@freescale.com>; Li Yang-Leo-R58472 <LeoLi@freescale.com>; > Arnd Bergmann <arnd@arndb.de>; Bjorn Helgaas <bhelgaas@google.com>; > Jingoo Han <jg1.han@samsung.com>; Zhou Wang > <wangzhou1@hisilicon.com>; Thomas Gleixner <tglx@linutronix.de> > Subject: Re: [PATCH v4 6/6] PCI: layerscape: add ls_pcie_msi_host_init > > Your reply was *still* base64-encoded and thus rejected by the vger mailing > lists. > > Minghuan wrote: > > On Thu, Oct 22, 2015 at 11:21:30AM -0500, Bjorn Helgaas wrote: > > > Minghuan wrote: > > > > On Wed, Oct 21, 2015 at 04:34:16PM -0500, Bjorn Helgaas wrote: > > > > > Hi Minghuan, > > > > > > > > > > On Fri, Oct 16, 2015 at 03:19:20PM +0800, Minghuan Lian wrote: > > > > > > Layerscape PCIe has its own MSI implementation. The patch > > > > > > registers > > > > > > ls_pcie_msi_host_init() to avoid using Designware's MSI. > > > > > > > > > > > > Signed-off-by: Minghuan Lian <Minghuan.Lian@freescale.com> > > > > > > --- > > > > > > Change log > > > > > > v4: split from [PATCH v3] PCI: layerscape: Add PCIe support > > > > > > for LS1043a and LS2080a > > > > > > > > > > > > drivers/pci/host/pci-layerscape.c | 17 +++++++++++++++++ > > > > > > 1 file changed, 17 insertions(+) > > > > > > > > > > > > diff --git a/drivers/pci/host/pci-layerscape.c > > > > > > b/drivers/pci/host/pci-layerscape.c > > > > > > index c53692a..8fac6c8 100644 > > > > > > --- a/drivers/pci/host/pci-layerscape.c > > > > > > +++ b/drivers/pci/host/pci-layerscape.c > > > > > > @@ -150,14 +150,31 @@ static void ls_pcie_host_init(struct > pcie_port *pp) > > > > > > iowrite32(0, pcie->dbi + PCIE_DBI_RO_WR_EN); } > > > > > > > > > > > > +static int ls_pcie_msi_host_init(struct pcie_port *pp, > > > > > > + struct msi_controller *chip) { > > > > > > + struct device_node *msi_node; > > > > > > + struct device_node *np = pp->dev->of_node; > > > > > > + > > > > > > + msi_node = of_parse_phandle(np, "msi-parent", 0); > > > > > > + if (!msi_node) { > > > > > > + dev_err(pp->dev, "failed to find msi-parent\n"); > > > > > > + return -EINVAL; > > > > > > + } > > > > > > + > > > > > > + return 0; > > > > > > > > > > I don't see how this can be right. I think it's OK if you want > > > > > to enforce the presence of "msi-parent", but the other > > > > > implementations of .msi_host_init (ks_dw_pcie_msi_host_init() > > > > > and the default implementation in dw_pcie_host_init()) both set > > > > > pp->irq_domain and call irq_create_mapping(). > > > > > > > > > > You don't do either of those, so I don't see how MSIs can work, > > > > > because I assume the generic DesignWare code will depend on > > > > > pp->irq_domain. If you're planning to add more > > > > > Layerscape-specific MSI support later, I think you should wait and > include this patch with that work. > > > > > > > Regarding MSI, both LS1021a and LS1043a use SCFG to implement it. I > have submitted patch: > > > > https://patchwork.kernel.org/patch/7411131/ > > > > https://patchwork.kernel.org/patch/7411141/ > > > > > > > While ls2085a use ITS for it, we just re-use the ITS driver. > > > > > > > I notice some platform MSI driver files were placed in pci/host > > > > folder not irqchip. If it is ok, I would like to change driver > > > > folder and re-submitted the MSI patch. > > > > > > I suppose you're referring to drivers/pci/host/pci-xgene-msi.c. > > > That file doesn't really have much PCI stuff in it. It does call > > > pci_msi_create_irq_domain(), but that's really the only PCI > > > interface or data structure it uses. So I don't know if > > > drivers/pci/host or drivers/irqchip is the best place for it and for > > > your irq-ls-scfg-msi.c. > > > > > > The connection between pci-xgene-msi.c and pci-xgene.c is not very > > > clear to me, and that's sort of what I'm complaining about here. > > > You're overriding a default MSI initialization method. Usually that > > > means you do the same thing as the default method, but in a > > > different way. You aren't doing the same thing at all, which makes > > > the code hard to review. > > > > > > Maybe a comment about how the MSI controller gets connected to > > > devices below this host bridge would be enough. > > > 1. We need to define callback function msi_host_init() to avoid the > > running desginware MSI related code Because our PCIe controller do not > > enable this feature. > > > > 2. we do not need to do anything such as bus->msi= ls_scfg_msi Because > > with the latest code, when PCIe controller device is created > > of_msi_configure() will be called and MSI domain pointed by > > 'msi-parent' will be bound to the device. pci_msi_get_domain(struct > > pci_dev *dev) -> dev_get_msi_domain(&dev->dev) will return this MSI > > domain. > > > > 3. I will add a comment in the next version. > > Don't bother, I added a comment and applied the patch like this: > > > commit 90cbdf8412d206f65ece3dcc53230e673da569c6 > Author: Minghuan Lian <Minghuan.Lian@freescale.com> > Date: Fri Oct 16 15:19:20 2015 +0800 > > PCI: layerscape: Add ls_pcie_msi_host_init() > > Layerscape PCIe has its own MSI implementation. > > Register ls_pcie_msi_host_init() to avoid using DesignWare's MSI. > > [bhelgaas: add comment] > Signed-off-by: Minghuan Lian <Minghuan.Lian@freescale.com> > Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> > > diff --git a/drivers/pci/host/pci-layerscape.c b/drivers/pci/host/pci-layerscape.c > index 6a9fa8a..1677890 100644 > --- a/drivers/pci/host/pci-layerscape.c > +++ b/drivers/pci/host/pci-layerscape.c > @@ -150,14 +150,37 @@ static void ls_pcie_host_init(struct pcie_port *pp) > iowrite32(0, pcie->dbi + PCIE_DBI_RO_WR_EN); } > > +static int ls_pcie_msi_host_init(struct pcie_port *pp, > + struct msi_controller *chip) > +{ > + struct device_node *msi_node; > + struct device_node *np = pp->dev->of_node; > + > + /* > + * The MSI domain is set by the generic of_msi_configure(). This > + * .msi_host_init() function keeps us from doing the default MSI > + * domain setup in dw_pcie_host_init() and also enforces the > + * requirement that "msi-parent" exists. > + */ > + msi_node = of_parse_phandle(np, "msi-parent", 0); > + if (!msi_node) { > + dev_err(pp->dev, "failed to find msi-parent\n"); > + return -EINVAL; > + } > + > + return 0; > +} > + > static struct pcie_host_ops ls1021_pcie_host_ops = { > .link_up = ls1021_pcie_link_up, > .host_init = ls1021_pcie_host_init, > + .msi_host_init = ls_pcie_msi_host_init, > }; > > static struct pcie_host_ops ls_pcie_host_ops = { > .link_up = ls_pcie_link_up, > .host_init = ls_pcie_host_init, > + .msi_host_init = ls_pcie_msi_host_init, > }; > > static struct ls_pcie_drvdata ls1021_drvdata = {
diff --git a/drivers/pci/host/pci-layerscape.c b/drivers/pci/host/pci-layerscape.c index 6a9fa8a..1677890 100644 --- a/drivers/pci/host/pci-layerscape.c +++ b/drivers/pci/host/pci-layerscape.c @@ -150,14 +150,37 @@ static void ls_pcie_host_init(struct pcie_port *pp) iowrite32(0, pcie->dbi + PCIE_DBI_RO_WR_EN); } +static int ls_pcie_msi_host_init(struct pcie_port *pp, + struct msi_controller *chip) +{ + struct device_node *msi_node; + struct device_node *np = pp->dev->of_node; + + /* + * The MSI domain is set by the generic of_msi_configure(). This + * .msi_host_init() function keeps us from doing the default MSI + * domain setup in dw_pcie_host_init() and also enforces the + * requirement that "msi-parent" exists. + */ + msi_node = of_parse_phandle(np, "msi-parent", 0); + if (!msi_node) { + dev_err(pp->dev, "failed to find msi-parent\n"); + return -EINVAL; + } + + return 0; +} + static struct pcie_host_ops ls1021_pcie_host_ops = { .link_up = ls1021_pcie_link_up, .host_init = ls1021_pcie_host_init, + .msi_host_init = ls_pcie_msi_host_init, }; static struct pcie_host_ops ls_pcie_host_ops = { .link_up = ls_pcie_link_up, .host_init = ls_pcie_host_init, + .msi_host_init = ls_pcie_msi_host_init, }; static struct ls_pcie_drvdata ls1021_drvdata = {