Re: [PATCH v5 2/5] PCI: designware: Add ARM64 support

[Zhou Wang <wangzhou1@hisilicon.com>]

On 2015/7/30 1:24, Lorenzo Pieralisi wrote:
> On Sat, Jul 25, 2015 at 04:21:23AM +0100, Zhou Wang wrote:
>> This patch tries to unify ARM32 and ARM64 PCIe in designware driver. Delete
>> function dw_pcie_setup, dw_pcie_scan_bus, dw_pcie_map_irq and struct hw_pci,
>> move related operations to dw_pcie_host_init. Also set pp->root_bus_nr = 0 in
>> each PCIe host driver which is based on pcie-designware. This patch also try
> 
> Memory for ports is kzalloc'ed, so there is no need to zero it. I still
> think that you should explain the root_bus_nr setting to 0 a bit
> better, why you make the change and why it is safe.
>

Hi Lorenzo,

This patch deletes dw_pcie_scan_bus and pass root_bus_nr directly to
pci_create_root_bus.

In past, we use:
pci_common_init_dev
	-> pcibios_init_hw
		-> hw->scan (dw_pcie_scan_bus)
to pass 0 to root_bus_nr in struct pcie_port. so I set root_bus_nr
in each driver which is based on dw to 0.

> [...]
> 
>> -int dw_pcie_host_init(struct pcie_port *pp)
>> +int __init dw_pcie_host_init(struct pcie_port *pp)
>>  {
>>         struct device_node *np = pp->dev->of_node;
>>         struct platform_device *pdev = to_platform_device(pp->dev);
>> -       struct of_pci_range range;
>> -       struct of_pci_range_parser parser;
>> +       struct pci_bus *bus;
>>         struct resource *cfg_res;
>> -       u32 val, na, ns;
>> +       LIST_HEAD(res);
>> +       u32 val, ns;
>>         const __be32 *addrp;
>>         int i, index, ret;
>> +       struct resource_entry *win;
>>
>> -       /* 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);
>> +       /* Find the number of cells in order to get the untranslated address */
>>         ns = of_n_size_cells(np);
>>
>>         cfg_res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "config");
>> @@ -392,78 +382,62 @@ int dw_pcie_host_init(struct pcie_port *pp)
>>                 dev_err(pp->dev, "missing *config* reg space\n");
>>         }
>>
>> -       if (of_pci_range_parser_init(&parser, np)) {
>> -               dev_err(pp->dev, "missing ranges property\n");
>> -               return -EINVAL;
>> -       }
>> +       ret = of_pci_get_host_bridge_resources(np, 0, 0xff, &res, &pp->io_base);
>> +       if (ret)
>> +               return ret;
>>
>>         /* Get the I/O and memory ranges from DT */
>> -       for_each_of_pci_range(&parser, &range) {
>> -               unsigned long restype = range.flags & IORESOURCE_TYPE_BITS;
>> -
>> -               if (restype == IORESOURCE_IO) {
>> -                       of_pci_range_to_resource(&range, np, &pp->io);
>> -                       pp->io.name = "I/O";
>> -                       pp->io.start = max_t(resource_size_t,
>> -                                            PCIBIOS_MIN_IO,
>> -                                            range.pci_addr + global_io_offset);
>> -                       pp->io.end = min_t(resource_size_t,
>> -                                          IO_SPACE_LIMIT,
>> -                                          range.pci_addr + range.size
>> -                                          + global_io_offset - 1);
>> -                       pp->io_size = resource_size(&pp->io);
>> -                       pp->io_bus_addr = range.pci_addr;
>> -                       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);
>> -               }
>> -               if (restype == IORESOURCE_MEM) {
>> -                       of_pci_range_to_resource(&range, np, &pp->mem);
>> -                       pp->mem.name = "MEM";
>> -                       pp->mem_size = resource_size(&pp->mem);
>> -                       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);
>> -               }
>> -               if (restype == 0) {
>> -                       of_pci_range_to_resource(&range, np, &pp->cfg);
>> -                       pp->cfg0_size = resource_size(&pp->cfg)/2;
>> -                       pp->cfg1_size = resource_size(&pp->cfg)/2;
>> -                       pp->cfg0_base = pp->cfg.start;
>> -                       pp->cfg1_base = pp->cfg.start + pp->cfg0_size;
>> +       resource_list_for_each_entry(win, &res) {
>> +               switch (resource_type(win->res)) {
>> +               case IORESOURCE_IO:
>> +                       pp->io = win->res;
>> +                       pp->io->name = "I/O";
>> +                       pp->io_size = resource_size(pp->io);
>> +                       pp->io_bus_addr = pp->io->start - win->offset;
>> +                       pp->io_mod_base = win->__res.start;
>> +                       ret = pci_remap_iospace(pp->io, pp->io_base);
>> +                       if (ret) {
>> +                               dev_warn(pp->dev, "error %d: failed to map resource %pR\n",
>> +                                        ret, pp->io);
>> +                               continue;
>> +                       }
>> +                       break;
>> +               case IORESOURCE_MEM:
>> +                       pp->mem = win->res;
>> +                       pp->mem->name = "MEM";
>> +                       pp->mem_size = resource_size(pp->mem);
>> +                       pp->mem_bus_addr = pp->mem->start - win->offset;
>> +                       pp->mem_mod_base = win->__res.start;
>> +                       break;
>> +               case 0:
>> +                       pp->cfg = win->res;
>> +                       pp->cfg0_size = resource_size(pp->cfg)/2;
>> +                       pp->cfg1_size = resource_size(pp->cfg)/2;
>> +                       pp->cfg0_base = pp->cfg->start;
>> +                       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->cfg1_mod_base = pp->cfg0_mod_base +
>> -                                           pp->cfg0_size;
>> +                       pp->cfg0_mod_base = win->__res.start;
>> +                       pp->cfg1_mod_base = pp->cfg0_mod_base + pp->cfg0_size;
>> +                       break;
>> +               case IORESOURCE_BUS:
>> +                       pp->busn = win->res;
>> +                       break;
>> +               default:
>> +                       continue;
>>                 }
>>         }
>>
>> -       ret = of_pci_parse_bus_range(np, &pp->busn);
>> -       if (ret < 0) {
>> -               pp->busn.name = np->name;
>> -               pp->busn.start = 0;
>> -               pp->busn.end = 0xff;
>> -               pp->busn.flags = IORESOURCE_BUS;
>> -               dev_dbg(pp->dev, "failed to parse bus-range property: %d, using default %pR\n",
>> -                       ret, &pp->busn);
>> -       }
>> -
>>         if (!pp->dbi_base) {
>> -               pp->dbi_base = devm_ioremap(pp->dev, pp->cfg.start,
>> -                                       resource_size(&pp->cfg));
>> +               pp->dbi_base = devm_ioremap(pp->dev, pp->cfg->start,
>> +                                       resource_size(pp->cfg));
>>                 if (!pp->dbi_base) {
>>                         dev_err(pp->dev, "error with ioremap\n");
>>                         return -ENOMEM;
>>                 }
>>         }
>>
>> -       pp->mem_base = pp->mem.start;
>> +       pp->mem_base = pp->mem->start;
>>
>>         if (!pp->va_cfg0_base) {
>>                 pp->va_cfg0_base = devm_ioremap(pp->dev, pp->cfg0_base,
>> @@ -524,15 +498,28 @@ int dw_pcie_host_init(struct pcie_port *pp)
>>         val |= PORT_LOGIC_SPEED_CHANGE;
>>         dw_pcie_wr_own_conf(pp, PCIE_LINK_WIDTH_SPEED_CONTROL, 4, val);
>>
>> -#ifdef CONFIG_PCI_MSI
>> -       dw_pcie_msi_chip.dev = pp->dev;
> 
> Is it safe to remove the dev assignment ?
>

I am not sure about this. But from James' test of v3 series, it seems that
it is OK for i.MX 6Quad board at least.

Maybe we'd better to add this in next version.

>> -       dw_pci.msi_ctrl = &dw_pcie_msi_chip;
>> +       bus = pci_create_root_bus(pp->dev, pp->root_bus_nr, &dw_pcie_ops,
>> +                             pp, &res);
>> +       if (!bus)
>> +               return -ENOMEM;
>> +
>> +#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
>> +       bus->msi = container_of(&pp->irq_domain, struct msi_controller, domain);
>> +#else
>> +       bus->msi = &dw_pcie_msi_chip;
>>  #endif
> 
> For the records, this patch conflicts with my MSI series:
> 
> http://lists.infradead.org/pipermail/linux-arm-kernel/2015-July/360461.html
> 
> Conflict resolution is easy but it is worth keeping in mind.
>

Thanks for reminding this.

Best Regards,
Zhou

> Thanks !
> Lorenzo
> 
>>
>> -       dw_pci.nr_controllers = 1;
>> -       dw_pci.private_data = (void **)&pp;
>> +       pci_scan_child_bus(bus);
>> +       if (pp->ops->scan_bus)
>> +               pp->ops->scan_bus(pp);
>>
>> -       pci_common_init_dev(pp->dev, &dw_pci);
>> +#ifdef CONFIG_ARM
>> +       /* support old dtbs that incorrectly describe IRQs */
>> +       pci_fixup_irqs(pci_common_swizzle, of_irq_parse_and_map_pci);
>> +#endif
>> +
>> +       pci_assign_unassigned_bus_resources(bus);
>> +       pci_bus_add_devices(bus);
>>
>>         return 0;
>>  }
>> @@ -633,7 +620,7 @@ static int dw_pcie_valid_config(struct pcie_port *pp,
>>  static int dw_pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
>>                         int size, u32 *val)
>>  {
>> -       struct pcie_port *pp = sys_to_pcie(bus->sysdata);
>> +       struct pcie_port *pp = bus->sysdata;
>>         int ret;
>>
>>         if (dw_pcie_valid_config(pp, bus, PCI_SLOT(devfn)) == 0) {
>> @@ -657,7 +644,7 @@ static int dw_pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
>>  static int dw_pcie_wr_conf(struct pci_bus *bus, u32 devfn,
>>                         int where, int size, u32 val)
>>  {
>> -       struct pcie_port *pp = sys_to_pcie(bus->sysdata);
>> +       struct pcie_port *pp = bus->sysdata;
>>         int ret;
>>
>>         if (dw_pcie_valid_config(pp, bus, PCI_SLOT(devfn)) == 0)
>> @@ -681,62 +668,6 @@ static struct pci_ops dw_pcie_ops = {
>>         .write = dw_pcie_wr_conf,
>>  };
>>
>> -static int dw_pcie_setup(int nr, struct pci_sys_data *sys)
>> -{
>> -       struct pcie_port *pp;
>> -
>> -       pp = sys_to_pcie(sys);
>> -
>> -       if (global_io_offset < SZ_1M && pp->io_size > 0) {
>> -               sys->io_offset = global_io_offset - pp->io_bus_addr;
>> -               pci_ioremap_io(global_io_offset, pp->io_base);
>> -               global_io_offset += SZ_64K;
>> -               pci_add_resource_offset(&sys->resources, &pp->io,
>> -                                       sys->io_offset);
>> -       }
>> -
>> -       sys->mem_offset = pp->mem.start - pp->mem_bus_addr;
>> -       pci_add_resource_offset(&sys->resources, &pp->mem, sys->mem_offset);
>> -       pci_add_resource(&sys->resources, &pp->busn);
>> -
>> -       return 1;
>> -}
>> -
>> -static struct pci_bus *dw_pcie_scan_bus(int nr, struct pci_sys_data *sys)
>> -{
>> -       struct pci_bus *bus;
>> -       struct pcie_port *pp = sys_to_pcie(sys);
>> -
>> -       pp->root_bus_nr = sys->busnr;
>> -       bus = pci_scan_root_bus(pp->dev, sys->busnr,
>> -                                 &dw_pcie_ops, sys, &sys->resources);
>> -       if (!bus)
>> -               return NULL;
>> -
>> -       if (bus && pp->ops->scan_bus)
>> -               pp->ops->scan_bus(pp);
>> -
>> -       return bus;
>> -}
>> -
>> -static int dw_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
>> -{
>> -       struct pcie_port *pp = sys_to_pcie(dev->bus->sysdata);
>> -       int irq;
>> -
>> -       irq = of_irq_parse_and_map_pci(dev, slot, pin);
>> -       if (!irq)
>> -               irq = pp->irq;
>> -
>> -       return irq;
>> -}
>> -
>> -static struct hw_pci dw_pci = {
>> -       .setup          = dw_pcie_setup,
>> -       .scan           = dw_pcie_scan_bus,
>> -       .map_irq        = dw_pcie_map_irq,
>> -};
>> -
>>  void dw_pcie_setup_rc(struct pcie_port *pp)
>>  {
>>         u32 val;
>> diff --git a/drivers/pci/host/pcie-designware.h b/drivers/pci/host/pcie-designware.h
>> index d0bbd27..efac57d 100644
>> --- a/drivers/pci/host/pcie-designware.h
>> +++ b/drivers/pci/host/pcie-designware.h
>> @@ -34,7 +34,7 @@ struct pcie_port {
>>         u64                     cfg1_mod_base;
>>         void __iomem            *va_cfg1_base;
>>         u32                     cfg1_size;
>> -       u64                     io_base;
>> +       resource_size_t         io_base;
>>         u64                     io_mod_base;
>>         phys_addr_t             io_bus_addr;
>>         u32                     io_size;
>> @@ -42,10 +42,10 @@ struct pcie_port {
>>         u64                     mem_mod_base;
>>         phys_addr_t             mem_bus_addr;
>>         u32                     mem_size;
>> -       struct resource         cfg;
>> -       struct resource         io;
>> -       struct resource         mem;
>> -       struct resource         busn;
>> +       struct resource         *cfg;
>> +       struct resource         *io;
>> +       struct resource         *mem;
>> +       struct resource         *busn;
>>         int                     irq;
>>         u32                     lanes;
>>         struct pcie_host_ops    *ops;
>> diff --git a/drivers/pci/host/pcie-spear13xx.c b/drivers/pci/host/pcie-spear13xx.c
>> index c49fbdc..03eb204 100644
>> --- a/drivers/pci/host/pcie-spear13xx.c
>> +++ b/drivers/pci/host/pcie-spear13xx.c
>> @@ -286,7 +286,7 @@ static int spear13xx_add_pcie_port(struct pcie_port *pp,
>>                 return ret;
>>         }
>>
>> -       pp->root_bus_nr = -1;
>> +       pp->root_bus_nr = 0;
>>         pp->ops = &spear13xx_pcie_host_ops;
>>
>>         ret = dw_pcie_host_init(pp);
>> --
>> 1.9.1
>>
>> --
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> 
> .
>