> -----Original Message-----
> From: Bjorn Helgaas [mailto:helg...@kernel.org]
> Sent: 21 October 2015 23:15
> To: Wangzhou (B)
> Cc: Bjorn Helgaas; jingooh...@gmail.com; pratyush.an...@gmail.com; Arnd
> Bergmann; li...@arm.linux.org.uk; thomas.petazz...@free-electrons.com;
> Gabriele Paoloni; lorenzo.pieral...@arm.com; james.mo...@arm.com;
> liviu.du...@arm.com; ja...@lakedaemon.net; r...@kernel.org;
> gabriel.fernan...@linaro.org; minghuan.l...@freescale.com; linux-
> p...@vger.kernel.org; linux-arm-ker...@lists.infradead.org;
> devicet...@vger.kernel.org; linux-kernel@vger.kernel.org; zhangjukuo;
> qiuzhenfa; liudongdong (C); qiujiang; xuwei (O); Liguozhu (Kenneth)
> Subject: Re: [PATCH v11 1/6] PCI: designware: move calculation of bus
> addresses to DRA7xx
>
> Hi Zhou & Gabriele,
Hi Bjorn, thanks for reviewing
>
> On Fri, Oct 16, 2015 at 06:23:36PM +0800, Zhou Wang wrote:
> > From: gabriele paoloni <gabriele.paol...@huawei.com>
> >
> > Commit f4c55c5a3f7f ("PCI: designware: Program ATU with untranslated
> > address") added the calculation of PCI BUS addresses in designware,
> > storing them in new fields added in "struct pcie_port". This
> > calculation is done for every designware user even if is only
> > applicable to DRA7xx.
> > This patch moves the calculation of the bus addresses to the DRA7xx
> > driver and is needed to allow the rework of designware to use
> > the new DT parsing API.
> >
> > Signed-off-by: Gabriele Paoloni <gabriele.paol...@huawei.com>
> > Signed-off-by: Zhou Wang <wangzh...@hisilicon.com>
> > Acked-by: Pratyush Anand <pratyush.an...@gmail.com>
> > ---
> > drivers/pci/host/pci-dra7xx.c | 13 +++++++++++++
> > drivers/pci/host/pcie-designware.c | 15 ++++-----------
> > 2 files changed, 17 insertions(+), 11 deletions(-)
> >
> > diff --git a/drivers/pci/host/pci-dra7xx.c b/drivers/pci/host/pci-dra7xx.c
> > index 199e29a..ebdffa0 100644
> > --- a/drivers/pci/host/pci-dra7xx.c
> > +++ b/drivers/pci/host/pci-dra7xx.c
> > @@ -62,6 +62,7 @@
> >
> > #define PCIECTRL_DRA7XX_CONF_PHY_CS 0x010C
> > #define LINK_UP BIT(16)
> > +#define CPU_TO_BUS_ADDR 0x0FFFFFFF
>
> "CPU_TO_BUS_ADDR" is a very generic name. Since you do have DRA7XX in
> other #defines and static symbols in this file, maybe it could be DRA7XX to
> make it obvious that it only applies here?
Ok will change to DRA7XX_CPU_TO_BUS_ADRR in v12
>
> >
> > struct dra7xx_pcie {
> > void __iomem *base;
> > @@ -151,6 +152,18 @@ static void dra7xx_pcie_enable_interrupts(struct
> pcie_port *pp)
> > static void dra7xx_pcie_host_init(struct pcie_port *pp)
> > {
> > dw_pcie_setup_rc(pp);
> > +
> > + if (pp->io_mod_base)
> > + pp->io_mod_base &= CPU_TO_BUS_ADDR;
>
> These are equivalent to
>
> pp->io_mod_base &= CPU_TO_BUS_ADDR;
>
> (You don't need to test whether they're zero first.)
>
Yes agreed, will change in v12
> > +
> > + if (pp->mem_mod_base)
> > + pp->mem_mod_base &= CPU_TO_BUS_ADDR;
> > +
> > + if (pp->cfg0_mod_base) {
> > + pp->cfg0_mod_base &= CPU_TO_BUS_ADDR;
> > + pp->cfg1_mod_base &= CPU_TO_BUS_ADDR;
> > + }
> > +
> > dra7xx_pcie_establish_link(pp);
> > if (IS_ENABLED(CONFIG_PCI_MSI))
> > dw_pcie_msi_init(pp);
> > diff --git a/drivers/pci/host/pcie-designware.c b/drivers/pci/host/pcie-
> designware.c
> > index 52aa6e3..75338a6 100644
> > --- a/drivers/pci/host/pcie-designware.c
> > +++ b/drivers/pci/host/pcie-designware.c
> > @@ -365,14 +365,10 @@ int dw_pcie_host_init(struct pcie_port *pp)
> > struct of_pci_range range;
> > struct of_pci_range_parser parser;
> > struct resource *cfg_res;
> > - u32 val, na, ns;
> > + u32 val, ns;
> > const __be32 *addrp;
> > int i, index, ret;
> >
> > - /* Find the address cell size and the number of cells in order to get
> > - * the untranslated address.
> > - */
> > - of_property_read_u32(np, "#address-cells", &na);
> > ns = of_n_size_cells(np);
> >
> > cfg_res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "config");
> > @@ -415,8 +411,7 @@ int dw_pcie_host_init(struct pcie_port *pp)
> > pp->io_base = range.cpu_addr;
> >
> > /* Find the untranslated IO space address */
> > - pp->io_mod_base = of_read_number(parser.range -
> > - parser.np + na, ns);
> > + pp->io_mod_base = range.cpu_addr;
>
> So apparently
>
> "of_read_number() == range.cpu_addr & CPU_TO_BUS_ADDR" on DRA7xx
> "of_read_number() == range.cpu_addr" everywhere else?
Yes correct
>
> Is that right? Is that a valid assumption, i.e., are we assuming
> anything about DTs in the field that we shouldn't?
Before I wrote a patch that was generic to accommodate intermediate level
of translation between PCI_addr -> BUS_addr -> CPU_addr
http://lists.infradead.org/pipermail/linux-arm-kernel/2015-July/360922.html
After discussion we agreed to solve it with a bitmask rather than adding
a field to of_pci_range to make it generic.
The bitmask only applies to DRA7xx
>
> > }
> > if (restype == IORESOURCE_MEM) {
> > of_pci_range_to_resource(&range, np, &pp->mem);
> > @@ -425,8 +420,7 @@ int dw_pcie_host_init(struct pcie_port *pp)
> > pp->mem_bus_addr = range.pci_addr;
> >
> > /* Find the untranslated MEM space address */
> > - pp->mem_mod_base = of_read_number(parser.range -
> > - parser.np + na, ns);
> > + pp->mem_mod_base = range.cpu_addr;
> > }
> > if (restype == 0) {
> > of_pci_range_to_resource(&range, np, &pp->cfg);
> > @@ -436,8 +430,7 @@ int dw_pcie_host_init(struct pcie_port *pp)
> > pp->cfg1_base = pp->cfg.start + pp->cfg0_size;
> >
> > /* Find the untranslated configuration space address */
> > - pp->cfg0_mod_base = of_read_number(parser.range -
> > - parser.np + na, ns);
> > + pp->cfg0_mod_base = range.cpu_addr;
> > pp->cfg1_mod_base = pp->cfg0_mod_base +
> > pp->cfg0_size;
> > }
> > --
> > 1.9.1
> >
> > --
> > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> > the body of a message to majord...@vger.kernel.org
> > More majordomo info at http://vger.kernel.org/majordomo-info.html
> > Please read the FAQ at http://www.tux.org/lkml/
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
