RE: [PATCH 2/3] PCI: designware: use untranslated address while programming ATU

From: Mohit KUMAR DCG
Date: Tue Jul 08 2014 - 23:41:23 EST


Hello Kishon,

> -----Original Message-----
> From: Kishon Vijay Abraham I [mailto:kishon@xxxxxx]
> Sent: Tuesday, July 08, 2014 6:01 PM
> To: devicetree@xxxxxxxxxxxxxxx; linux-doc@xxxxxxxxxxxxxxx; linux-
> pci@xxxxxxxxxxxxxxx; jg1.han@xxxxxxxxxxx; bhelgaas@xxxxxxxxxx; Mohit
> KUMAR DCG; linux-kernel@xxxxxxxxxxxxxxx
> Cc: grant.likely@xxxxxxxxxx; Jason Gunthorpe; Marek Vasut; Arnd Bergmann
> Subject: Re: [PATCH 2/3] PCI: designware: use untranslated address while
> programming ATU
>
> Hi Mohit, Jingoo,
>
> On Wednesday 25 June 2014 11:26 PM, Kishon Vijay Abraham I wrote:
> > In DRA7, the cpu sees 32bit address, but the pcie controller can see
> > only 28bit address. So whenever the cpu issues a read/write request,
> > the 4 most significant bits are used by L3 to determine the target controller.
> > For example, the cpu reserves 0x2000_0000 - 0x2FFF_FFFF for PCIe
> > controller but the PCIe controller will see only (0x000_0000 -
> > 0xFFF_FFF). So for programming the outbound translation window the
> *base* should be programmed as 0x000_0000.
> > Whenever we try to write to say 0x2000_0000, it will be translated to
> > whatever we have programmed in the translation window with base as
> 0x000_0000.
> >
> > This is needed when the dt node is modelled something like below axi {
> > compatible = "simple-bus";
> > #size-cells = <1>;
> > #address-cells = <1>;
> > ranges = <0x0 0x20000000 0x10000000 // 28-bit bus
> > 0x51000000 0x51000000 0x3000>;
> > pcie@51000000 {
> > reg = <0x1000 0x2000>, <0x51002000 0x14c>, <0x51000000
> 0x2000>;
> > reg-names = "config", "ti_conf", "rc_dbics";
> > #address-cells = <3>;
> > #size-cells = <2>;
> > ranges = <0x81000000 0 0 0x03000 0 0x00010000
> > 0x82000000 0 0x20013000 0x13000 0 0xffed000>;
> > };
> > };
> >
> > Here the CPU address for configuration space is 0x20013000 and the
> > controller address for configuration space is 0x13000. The controller
> > address should be used while programming the ATU (in order for
> > translation to happen properly in DRA7xx).
>
> Are you okay with this patch? Can you give your Reviewed-by/Acked-by?
>

- looks fine to me.
Reviewed-by: Mohit Kumar<mohit.kumar@xxxxxx>

Thanks
Mohit
> Cheers
> Kishon
> >
> > Cc: Jason Gunthorpe <jgunthorpe@xxxxxxxxxxxxxxxxxxxx>
> > Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> > Cc: Mohit Kumar <mohit.kumar@xxxxxx>
> > Cc: Jingoo Han <jg1.han@xxxxxxxxxxx>
> > Cc: Marek Vasut <marex@xxxxxxx>
> > Cc: Arnd Bergmann <arnd@xxxxxxxx>
> > Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
> > ---
> > drivers/pci/host/pcie-designware.c | 49
> ++++++++++++++++++++++++++++--------
> > drivers/pci/host/pcie-designware.h | 4 +++
> > 2 files changed, 42 insertions(+), 11 deletions(-)
> >
> > diff --git a/drivers/pci/host/pcie-designware.c
> > b/drivers/pci/host/pcie-designware.c
> > index 0b7b455..11aba6d 100644
> > --- a/drivers/pci/host/pcie-designware.c
> > +++ b/drivers/pci/host/pcie-designware.c
> > @@ -401,8 +401,15 @@ int __init 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;
> > - int i;
> > + u32 val, na, ns;
> > + const __be32 *addrp;
> > + int i, index;
> > +
> > + /* 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");
> > if (cfg_res) {
> > @@ -410,6 +417,12 @@ int __init dw_pcie_host_init(struct pcie_port *pp)
> > pp->config.cfg1_size = resource_size(cfg_res)/2;
> > pp->cfg0_base = cfg_res->start;
> > pp->cfg1_base = cfg_res->start + pp->config.cfg0_size;
> > +
> > + /* Find the untranslated configuration space address */
> > + index = of_property_match_string(np, "reg-names",
> "config");
> > + addrp = of_get_address(np, index, false, false);
> > + pp->cfg0_mod_addr = of_read_number(addrp, ns);
> > + pp->cfg1_mod_addr = pp->cfg0_mod_addr + pp-
> >config.cfg0_size;
> > } else {
> > dev_err(pp->dev, "missing *config* reg space\n");
> > }
> > @@ -435,12 +448,20 @@ int __init dw_pcie_host_init(struct pcie_port
> *pp)
> > pp->config.io_size = resource_size(&pp->io);
> > pp->config.io_bus_addr = range.pci_addr;
> > pp->io_base = range.cpu_addr;
> > +
> > + /* Find the untranslated IO space address */
> > + pp->io_mod_addr = of_read_number(parser.range -
> > + parser.np + na, ns);
> > }
> > if (restype == IORESOURCE_MEM) {
> > of_pci_range_to_resource(&range, np, &pp->mem);
> > pp->mem.name = "MEM";
> > pp->config.mem_size = resource_size(&pp->mem);
> > pp->config.mem_bus_addr = range.pci_addr;
> > +
> > + /* Find the untranslated MEM space address */
> > + pp->mem_mod_addr =
> of_read_number(parser.range -
> > + parser.np + na, ns);
> > }
> > if (restype == 0) {
> > of_pci_range_to_resource(&range, np, &pp->cfg);
> @@ -448,6 +469,12
> > @@ int __init dw_pcie_host_init(struct pcie_port *pp)
> > pp->config.cfg1_size = resource_size(&pp->cfg)/2;
> > pp->cfg0_base = pp->cfg.start;
> > pp->cfg1_base = pp->cfg.start + pp-
> >config.cfg0_size;
> > +
> > + /* Find the untranslated configuration space address
> */
> > + pp->cfg0_mod_addr =
> of_read_number(parser.range -
> > + parser.np + na, ns);
> > + pp->cfg1_mod_addr = pp->cfg0_mod_addr +
> > + pp->config.cfg0_size;
> > }
> > }
> >
> > @@ -522,9 +549,9 @@ static void dw_pcie_prog_viewport_cfg0(struct
> pcie_port *pp, u32 busdev)
> > /* Program viewport 0 : OUTBOUND : CFG0 */
> > dw_pcie_writel_rc(pp, PCIE_ATU_REGION_OUTBOUND |
> PCIE_ATU_REGION_INDEX0,
> > PCIE_ATU_VIEWPORT);
> > - dw_pcie_writel_rc(pp, pp->cfg0_base, PCIE_ATU_LOWER_BASE);
> > - dw_pcie_writel_rc(pp, (pp->cfg0_base >> 32),
> PCIE_ATU_UPPER_BASE);
> > - dw_pcie_writel_rc(pp, pp->cfg0_base + pp->config.cfg0_size - 1,
> > + dw_pcie_writel_rc(pp, pp->cfg0_mod_addr,
> PCIE_ATU_LOWER_BASE);
> > + dw_pcie_writel_rc(pp, (pp->cfg0_mod_addr >> 32),
> PCIE_ATU_UPPER_BASE);
> > + dw_pcie_writel_rc(pp, pp->cfg0_mod_addr + pp->config.cfg0_size -
> 1,
> > PCIE_ATU_LIMIT);
> > dw_pcie_writel_rc(pp, busdev, PCIE_ATU_LOWER_TARGET);
> > dw_pcie_writel_rc(pp, 0, PCIE_ATU_UPPER_TARGET); @@ -538,9
> +565,9 @@
> > static void dw_pcie_prog_viewport_cfg1(struct pcie_port *pp, u32 busdev)
> > dw_pcie_writel_rc(pp, PCIE_ATU_REGION_OUTBOUND |
> PCIE_ATU_REGION_INDEX1,
> > PCIE_ATU_VIEWPORT);
> > dw_pcie_writel_rc(pp, PCIE_ATU_TYPE_CFG1, PCIE_ATU_CR1);
> > - dw_pcie_writel_rc(pp, pp->cfg1_base, PCIE_ATU_LOWER_BASE);
> > - dw_pcie_writel_rc(pp, (pp->cfg1_base >> 32),
> PCIE_ATU_UPPER_BASE);
> > - dw_pcie_writel_rc(pp, pp->cfg1_base + pp->config.cfg1_size - 1,
> > + dw_pcie_writel_rc(pp, pp->cfg1_mod_addr,
> PCIE_ATU_LOWER_BASE);
> > + dw_pcie_writel_rc(pp, (pp->cfg1_mod_addr >> 32),
> PCIE_ATU_UPPER_BASE);
> > + dw_pcie_writel_rc(pp, pp->cfg1_mod_addr + pp->config.cfg1_size -
> 1,
> > PCIE_ATU_LIMIT);
> > dw_pcie_writel_rc(pp, busdev, PCIE_ATU_LOWER_TARGET);
> > dw_pcie_writel_rc(pp, 0, PCIE_ATU_UPPER_TARGET); @@ -553,9
> +580,9 @@
> > static void dw_pcie_prog_viewport_mem_outbound(struct pcie_port *pp)
> > dw_pcie_writel_rc(pp, PCIE_ATU_REGION_OUTBOUND |
> PCIE_ATU_REGION_INDEX0,
> > PCIE_ATU_VIEWPORT);
> > dw_pcie_writel_rc(pp, PCIE_ATU_TYPE_MEM, PCIE_ATU_CR1);
> > - dw_pcie_writel_rc(pp, pp->mem_base, PCIE_ATU_LOWER_BASE);
> > - dw_pcie_writel_rc(pp, (pp->mem_base >> 32),
> PCIE_ATU_UPPER_BASE);
> > - dw_pcie_writel_rc(pp, pp->mem_base + pp->config.mem_size - 1,
> > + dw_pcie_writel_rc(pp, pp->mem_mod_addr,
> PCIE_ATU_LOWER_BASE);
> > + dw_pcie_writel_rc(pp, (pp->mem_mod_addr >> 32),
> PCIE_ATU_UPPER_BASE);
> > + dw_pcie_writel_rc(pp, pp->mem_mod_addr + pp->config.mem_size
> - 1,
> > PCIE_ATU_LIMIT);
> > dw_pcie_writel_rc(pp, pp->config.mem_bus_addr,
> PCIE_ATU_LOWER_TARGET);
> > dw_pcie_writel_rc(pp, upper_32_bits(pp->config.mem_bus_addr),
> > diff --git a/drivers/pci/host/pcie-designware.h
> > b/drivers/pci/host/pcie-designware.h
> > index 77f592f..13828f8 100644
> > --- a/drivers/pci/host/pcie-designware.h
> > +++ b/drivers/pci/host/pcie-designware.h
> > @@ -36,11 +36,15 @@ struct pcie_port {
> > u8 root_bus_nr;
> > void __iomem *dbi_base;
> > u64 cfg0_base;
> > + u64 cfg0_mod_addr;
> > void __iomem *va_cfg0_base;
> > u64 cfg1_base;
> > + u64 cfg1_mod_addr;
> > void __iomem *va_cfg1_base;
> > u64 io_base;
> > + u64 io_mod_addr;
> > u64 mem_base;
> > + u64 mem_mod_addr;
> > struct resource cfg;
> > struct resource io;
> > struct resource mem;
> >
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