Re: [PATCH v12 05/12] PCI: OF: Fix the conversion of IO ranges into IO resources.

From: Liviu Dudau
Date: Tue Sep 23 2014 - 21:14:23 EST

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On Tue, Sep 23, 2014 at 06:22:53PM -0600, Bjorn Helgaas wrote:
> [+cc Andrew]
>
> On Tue, Sep 23, 2014 at 08:01:07PM +0100, Liviu Dudau wrote:
> > The ranges property for a host bridge controller in DT describes
> > the mapping between the PCI bus address and the CPU physical address.
> > The resources framework however expects that the IO resources start
> > at a pseudo "port" address 0 (zero) and have a maximum size of IO_SPACE_LIMIT.
> > The conversion from pci ranges to resources failed to take that into account,
> > returning a CPU physical address instead of a port number.
> >
> > Also fix all the drivers that depend on the old behaviour by fetching
> > the CPU physical address based on the port number where it is being needed.
> >
> > Cc: Grant Likely <grant.likely@xxxxxxxxxx>
> > Cc: Rob Herring <robh+dt@xxxxxxxxxx>
> > Cc: Arnd Bergmann <arnd@xxxxxxxx>
> > Acked-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
> > Cc: Thierry Reding <thierry.reding@xxxxxxxxx>
> > Cc: Simon Horman <horms@xxxxxxxxxxxx>
> > Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
> > Signed-off-by: Liviu Dudau <Liviu.Dudau@xxxxxxx>
> > ---
> > arch/arm/mach-integrator/pci_v3.c | 23 ++++++++++----------
> > drivers/of/address.c | 44 +++++++++++++++++++++++++++++++++++----
> > drivers/pci/host/pci-tegra.c | 10 ++++++---
> > drivers/pci/host/pcie-rcar.c | 21 +++++++++++++------
> > include/linux/of_address.h | 15 ++++++-------
> > 5 files changed, 82 insertions(+), 31 deletions(-)
> > ...
>
> The of_pci_range_to_resource() implementation in drivers/of/address.c is
> always compiled when CONFIG_OF_ADDRESS=y, but when CONFIG_OF_ADDRESS=y and
> CONFIG_PCI is not set, we get the static inline version from
> include/linux/of_address.h as well, causing a redefinition error.
>
> > diff --git a/drivers/of/address.c b/drivers/of/address.c
> > @@ -957,12 +957,48 @@ bool of_dma_is_coherent(struct device_node *np)
> > ...
> > +int of_pci_range_to_resource(struct of_pci_range *range,
> > + struct device_node *np, struct resource *res)
>
> > diff --git a/include/linux/of_address.h b/include/linux/of_address.h
> > ...
> > #else /* CONFIG_OF_ADDRESS && CONFIG_PCI */
> > static inline int of_pci_address_to_resource(struct device_node *dev, int bar,
> > struct resource *r)
> > @@ -144,6 +139,12 @@ static inline int of_pci_address_to_resource(struct device_node *dev, int bar,
> > return -ENOSYS;
> > }
> >
> > +static inline int of_pci_range_to_resource(struct of_pci_range *range,
> > + struct device_node *np, struct resource *res)
> > +{
> > + return -ENOSYS;
> > +}
>
> My proposal to fix it is the following three patches. The first moves the
> inline version of of_pci_range_to_resource() into the existing "#if
> defined(CONFIG_OF_ADDRESS) && defined(CONFIG_PCI)" block.
>
> Andrew added it (and some other PCI-related things) with 29b635c00f3e
> ("of/pci: Provide support for parsing PCI DT ranges property") to
> of_address.h outside of any ifdefs, so it's always available. Maybe
> there's a reason that's needed in the non-CONFIG_PCI case, but I didn't see
> it with a quick look.
>
> The second moves of_pci_range_to_resource() to address.c, still inside the
> "#ifdef CONFIG_PCI" block.

Hi Bjorn,

Looks good to me. Sorry for messing this up, I've tested a combination of
CONFIG_PCI=y and CONFIG_PCI=n but it looks like I've only tested
CONFIG_OF_ADDRESS=CONFIG_PCI (both enabled or both disabled).

Best regards,
Liviu

>
> Bjorn
>
>
> commit 95a60df1c2d400c676ab1d20271735e2b4735437
> Author: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> Date: Tue Sep 23 17:27:42 2014 -0600
>
> of/pci: Define of_pci_range_to_resource() only when CONFIG_PCI=y
>
> of_pci_range_to_resource() was previously defined always, but it's only
> used by PCI code, so move the definition inside the CONFIG_OF_ADDRESS &&
> CONFIG_PCI block.
>
> Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
>
> diff --git a/include/linux/of_address.h b/include/linux/of_address.h
> index f8cc7daa420c..ecf913cf53b2 100644
> --- a/include/linux/of_address.h
> +++ b/include/linux/of_address.h
> @@ -23,17 +23,6 @@ struct of_pci_range {
> #define for_each_of_pci_range(parser, range) \
> for (; of_pci_range_parser_one(parser, range);)
>
> -static inline void of_pci_range_to_resource(struct of_pci_range *range,
> - struct device_node *np,
> - struct resource *res)
> -{
> - res->flags = range->flags;
> - res->start = range->cpu_addr;
> - res->end = range->cpu_addr + range->size - 1;
> - res->parent = res->child = res->sibling = NULL;
> - res->name = np->full_name;
> -}
> -
> /* Translate a DMA address from device space to CPU space */
> extern u64 of_translate_dma_address(struct device_node *dev,
> const __be32 *in_addr);
> @@ -140,6 +129,18 @@ extern const __be32 *of_get_pci_address(struct device_node *dev, int bar_no,
> u64 *size, unsigned int *flags);
> extern int of_pci_address_to_resource(struct device_node *dev, int bar,
> struct resource *r);
> +
> +static inline void of_pci_range_to_resource(struct of_pci_range *range,
> + struct device_node *np,
> + struct resource *res)
> +{
> + res->flags = range->flags;
> + res->start = range->cpu_addr;
> + res->end = range->cpu_addr + range->size - 1;
> + res->parent = res->child = res->sibling = NULL;
> + res->name = np->full_name;
> +}
> +
> #else /* CONFIG_OF_ADDRESS && CONFIG_PCI */
> static inline int of_pci_address_to_resource(struct device_node *dev, int bar,
> struct resource *r)
> @@ -155,4 +156,3 @@ static inline const __be32 *of_get_pci_address(struct device_node *dev,
> #endif /* CONFIG_OF_ADDRESS && CONFIG_PCI */
>
> #endif /* __OF_ADDRESS_H */
> -
>
> commit 501857889201723da06aab0ec68186a5beaa9f72
> Author: Liviu Dudau <Liviu.Dudau@xxxxxxx>
> Date: Tue Sep 23 20:01:06 2014 +0100
>
> of/pci: Move of_pci_range_to_resources() to of/address.c
>
> We need to enhance of_pci_range_to_resources() enough that it won't make
> sense for it to be inline anymore. Move it to drivers/of/address.c,
> keeping it under #ifdef CONFIG_PCI.
>
> [bhelgaas: drop extra detail from changelog, move def under CONFIG_PCI]
> Signed-off-by: Liviu Dudau <Liviu.Dudau@xxxxxxx>
> Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> CC: Grant Likely <grant.likely@xxxxxxxxxx>
> CC: Rob Herring <robh+dt@xxxxxxxxxx>
> CC: Arnd Bergmann <arnd@xxxxxxxx>
> CC: Catalin Marinas <catalin.marinas@xxxxxxx>
>
> diff --git a/drivers/of/address.c b/drivers/of/address.c
> index 758d4f04d4aa..327a57410797 100644
> --- a/drivers/of/address.c
> +++ b/drivers/of/address.c
> @@ -295,6 +295,15 @@ struct of_pci_range *of_pci_range_parser_one(struct of_pci_range_parser *parser,
> }
> EXPORT_SYMBOL_GPL(of_pci_range_parser_one);
>
> +void of_pci_range_to_resource(struct of_pci_range *range,
> + struct device_node *np, struct resource *res)
> +{
> + res->flags = range->flags;
> + res->start = range->cpu_addr;
> + res->end = range->cpu_addr + range->size - 1;
> + res->parent = res->child = res->sibling = NULL;
> + res->name = np->full_name;
> +}
> #endif /* CONFIG_PCI */
>
> /*
> diff --git a/include/linux/of_address.h b/include/linux/of_address.h
> index ecf913cf53b2..fa20aa15463d 100644
> --- a/include/linux/of_address.h
> +++ b/include/linux/of_address.h
> @@ -129,18 +129,9 @@ extern const __be32 *of_get_pci_address(struct device_node *dev, int bar_no,
> u64 *size, unsigned int *flags);
> extern int of_pci_address_to_resource(struct device_node *dev, int bar,
> struct resource *r);
> -
> -static inline void of_pci_range_to_resource(struct of_pci_range *range,
> - struct device_node *np,
> - struct resource *res)
> -{
> - res->flags = range->flags;
> - res->start = range->cpu_addr;
> - res->end = range->cpu_addr + range->size - 1;
> - res->parent = res->child = res->sibling = NULL;
> - res->name = np->full_name;
> -}
> -
> +extern void of_pci_range_to_resource(struct of_pci_range *range,
> + struct device_node *np,
> + struct resource *res);
> #else /* CONFIG_OF_ADDRESS && CONFIG_PCI */
> static inline int of_pci_address_to_resource(struct device_node *dev, int bar,
> struct resource *r)
>
> commit e01c1ebeee0bc45d6ac5f52b22c57d278799869b
> Author: Liviu Dudau <Liviu.Dudau@xxxxxxx>
> Date: Tue Sep 23 20:01:07 2014 +0100
>
> of/pci: Fix the conversion of IO ranges into IO resources
>
> The ranges property for a host bridge controller in DT describes the
> mapping between the PCI bus address and the CPU physical address. The
> resources framework however expects that the IO resources start at a pseudo
> "port" address 0 (zero) and have a maximum size of IO_SPACE_LIMIT. The
> conversion from PCI ranges to resources failed to take that into account,
> returning a CPU physical address instead of a port number.
>
> Also fix all the drivers that depend on the old behaviour by fetching the
> CPU physical address based on the port number where it is being needed.
>
> Signed-off-by: Liviu Dudau <Liviu.Dudau@xxxxxxx>
> Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> Acked-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
> CC: Grant Likely <grant.likely@xxxxxxxxxx>
> CC: Rob Herring <robh+dt@xxxxxxxxxx>
> CC: Arnd Bergmann <arnd@xxxxxxxx>
> CC: Thierry Reding <thierry.reding@xxxxxxxxx>
> CC: Simon Horman <horms@xxxxxxxxxxxx>
> CC: Catalin Marinas <catalin.marinas@xxxxxxx>
>
> diff --git a/arch/arm/mach-integrator/pci_v3.c b/arch/arm/mach-integrator/pci_v3.c
> index 05e1f73a1e8d..c186a17c2cff 100644
> --- a/arch/arm/mach-integrator/pci_v3.c
> +++ b/arch/arm/mach-integrator/pci_v3.c
> @@ -660,6 +660,7 @@ static void __init pci_v3_preinit(void)
> {
> unsigned long flags;
> unsigned int temp;
> + phys_addr_t io_address = pci_pio_to_address(io_mem.start);
>
> pcibios_min_mem = 0x00100000;
>
> @@ -701,7 +702,7 @@ static void __init pci_v3_preinit(void)
> /*
> * Setup window 2 - PCI IO
> */
> - v3_writel(V3_LB_BASE2, v3_addr_to_lb_base2(io_mem.start) |
> + v3_writel(V3_LB_BASE2, v3_addr_to_lb_base2(io_address) |
> V3_LB_BASE_ENABLE);
> v3_writew(V3_LB_MAP2, v3_addr_to_lb_map2(0));
>
> @@ -742,6 +743,7 @@ static void __init pci_v3_preinit(void)
> static void __init pci_v3_postinit(void)
> {
> unsigned int pci_cmd;
> + phys_addr_t io_address = pci_pio_to_address(io_mem.start);
>
> pci_cmd = PCI_COMMAND_MEMORY |
> PCI_COMMAND_MASTER | PCI_COMMAND_INVALIDATE;
> @@ -758,7 +760,7 @@ static void __init pci_v3_postinit(void)
> "interrupt: %d\n", ret);
> #endif
>
> - register_isa_ports(non_mem.start, io_mem.start, 0);
> + register_isa_ports(non_mem.start, io_address, 0);
> }
>
> /*
> @@ -867,33 +869,32 @@ static int __init pci_v3_probe(struct platform_device *pdev)
>
> for_each_of_pci_range(&parser, &range) {
> if (!range.flags) {
> - of_pci_range_to_resource(&range, np, &conf_mem);
> + ret = of_pci_range_to_resource(&range, np, &conf_mem);
> conf_mem.name = "PCIv3 config";
> }
> if (range.flags & IORESOURCE_IO) {
> - of_pci_range_to_resource(&range, np, &io_mem);
> + ret = of_pci_range_to_resource(&range, np, &io_mem);
> io_mem.name = "PCIv3 I/O";
> }
> if ((range.flags & IORESOURCE_MEM) &&
> !(range.flags & IORESOURCE_PREFETCH)) {
> non_mem_pci = range.pci_addr;
> non_mem_pci_sz = range.size;
> - of_pci_range_to_resource(&range, np, &non_mem);
> + ret = of_pci_range_to_resource(&range, np, &non_mem);
> non_mem.name = "PCIv3 non-prefetched mem";
> }
> if ((range.flags & IORESOURCE_MEM) &&
> (range.flags & IORESOURCE_PREFETCH)) {
> pre_mem_pci = range.pci_addr;
> pre_mem_pci_sz = range.size;
> - of_pci_range_to_resource(&range, np, &pre_mem);
> + ret = of_pci_range_to_resource(&range, np, &pre_mem);
> pre_mem.name = "PCIv3 prefetched mem";
> }
> - }
>
> - if (!conf_mem.start || !io_mem.start ||
> - !non_mem.start || !pre_mem.start) {
> - dev_err(&pdev->dev, "missing ranges in device node\n");
> - return -EINVAL;
> + if (ret < 0) {
> + dev_err(&pdev->dev, "missing ranges in device node\n");
> + return ret;
> + }
> }
>
> pci_v3.map_irq = of_irq_parse_and_map_pci;
> diff --git a/drivers/of/address.c b/drivers/of/address.c
> index 327a57410797..afdb78299f61 100644
> --- a/drivers/of/address.c
> +++ b/drivers/of/address.c
> @@ -295,14 +295,50 @@ struct of_pci_range *of_pci_range_parser_one(struct of_pci_range_parser *parser,
> }
> EXPORT_SYMBOL_GPL(of_pci_range_parser_one);
>
> -void of_pci_range_to_resource(struct of_pci_range *range,
> - struct device_node *np, struct resource *res)
> +/*
> + * of_pci_range_to_resource - Create a resource from an of_pci_range
> + * @range: the PCI range that describes the resource
> + * @np: device node where the range belongs to
> + * @res: pointer to a valid resource that will be updated to
> + * reflect the values contained in the range.
> + *
> + * Returns EINVAL if the range cannot be converted to resource.
> + *
> + * Note that if the range is an IO range, the resource will be converted
> + * using pci_address_to_pio() which can fail if it is called too early or
> + * if the range cannot be matched to any host bridge IO space (our case here).
> + * To guard against that we try to register the IO range first.
> + * If that fails we know that pci_address_to_pio() will do too.
> + */
> +int of_pci_range_to_resource(struct of_pci_range *range,
> + struct device_node *np, struct resource *res)
> {
> + int err;
> res->flags = range->flags;
> - res->start = range->cpu_addr;
> - res->end = range->cpu_addr + range->size - 1;
> res->parent = res->child = res->sibling = NULL;
> res->name = np->full_name;
> +
> + if (res->flags & IORESOURCE_IO) {
> + unsigned long port;
> + err = pci_register_io_range(range->cpu_addr, range->size);
> + if (err)
> + goto invalid_range;
> + port = pci_address_to_pio(range->cpu_addr);
> + if (port == (unsigned long)-1) {
> + err = -EINVAL;
> + goto invalid_range;
> + }
> + res->start = port;
> + } else {
> + res->start = range->cpu_addr;
> + }
> + res->end = res->start + range->size - 1;
> + return 0;
> +
> +invalid_range:
> + res->start = (resource_size_t)OF_BAD_ADDR;
> + res->end = (resource_size_t)OF_BAD_ADDR;
> + return err;
> }
> #endif /* CONFIG_PCI */
>
> diff --git a/drivers/pci/host/pci-tegra.c b/drivers/pci/host/pci-tegra.c
> index 0fb0fdb223d5..946935db62b6 100644
> --- a/drivers/pci/host/pci-tegra.c
> +++ b/drivers/pci/host/pci-tegra.c
> @@ -626,13 +626,14 @@ DECLARE_PCI_FIXUP_FINAL(PCI_ANY_ID, PCI_ANY_ID, tegra_pcie_relax_enable);
> static int tegra_pcie_setup(int nr, struct pci_sys_data *sys)
> {
> struct tegra_pcie *pcie = sys_to_pcie(sys);
> + phys_addr_t io_start = pci_pio_to_address(pcie->io.start);
>
> pci_add_resource_offset(&sys->resources, &pcie->mem, sys->mem_offset);
> pci_add_resource_offset(&sys->resources, &pcie->prefetch,
> sys->mem_offset);
> pci_add_resource(&sys->resources, &pcie->busn);
>
> - pci_ioremap_io(nr * SZ_64K, pcie->io.start);
> + pci_ioremap_io(nr * SZ_64K, io_start);
>
> return 1;
> }
> @@ -737,6 +738,7 @@ static irqreturn_t tegra_pcie_isr(int irq, void *arg)
> static void tegra_pcie_setup_translations(struct tegra_pcie *pcie)
> {
> u32 fpci_bar, size, axi_address;
> + phys_addr_t io_start = pci_pio_to_address(pcie->io.start);
>
> /* Bar 0: type 1 extended configuration space */
> fpci_bar = 0xfe100000;
> @@ -749,7 +751,7 @@ static void tegra_pcie_setup_translations(struct tegra_pcie *pcie)
> /* Bar 1: downstream IO bar */
> fpci_bar = 0xfdfc0000;
> size = resource_size(&pcie->io);
> - axi_address = pcie->io.start;
> + axi_address = io_start;
> afi_writel(pcie, axi_address, AFI_AXI_BAR1_START);
> afi_writel(pcie, size >> 12, AFI_AXI_BAR1_SZ);
> afi_writel(pcie, fpci_bar, AFI_FPCI_BAR1);
> @@ -1520,7 +1522,9 @@ static int tegra_pcie_parse_dt(struct tegra_pcie *pcie)
> }
>
> for_each_of_pci_range(&parser, &range) {
> - of_pci_range_to_resource(&range, np, &res);
> + err = of_pci_range_to_resource(&range, np, &res);
> + if (err < 0)
> + return err;
>
> switch (res.flags & IORESOURCE_TYPE_BITS) {
> case IORESOURCE_IO:
> diff --git a/drivers/pci/host/pcie-rcar.c b/drivers/pci/host/pcie-rcar.c
> index 4884ee5e07d4..61158e03ab5f 100644
> --- a/drivers/pci/host/pcie-rcar.c
> +++ b/drivers/pci/host/pcie-rcar.c
> @@ -323,6 +323,7 @@ static void rcar_pcie_setup_window(int win, struct rcar_pcie *pcie)
>
> /* Setup PCIe address space mappings for each resource */
> resource_size_t size;
> + resource_size_t res_start;
> u32 mask;
>
> rcar_pci_write_reg(pcie, 0x00000000, PCIEPTCTLR(win));
> @@ -335,8 +336,13 @@ static void rcar_pcie_setup_window(int win, struct rcar_pcie *pcie)
> mask = (roundup_pow_of_two(size) / SZ_128) - 1;
> rcar_pci_write_reg(pcie, mask << 7, PCIEPAMR(win));
>
> - rcar_pci_write_reg(pcie, upper_32_bits(res->start), PCIEPARH(win));
> - rcar_pci_write_reg(pcie, lower_32_bits(res->start), PCIEPARL(win));
> + if (res->flags & IORESOURCE_IO)
> + res_start = pci_pio_to_address(res->start);
> + else
> + res_start = res->start;
> +
> + rcar_pci_write_reg(pcie, upper_32_bits(res_start), PCIEPARH(win));
> + rcar_pci_write_reg(pcie, lower_32_bits(res_start), PCIEPARL(win));
>
> /* First resource is for IO */
> mask = PAR_ENABLE;
> @@ -363,9 +369,10 @@ static int rcar_pcie_setup(int nr, struct pci_sys_data *sys)
>
> rcar_pcie_setup_window(i, pcie);
>
> - if (res->flags & IORESOURCE_IO)
> - pci_ioremap_io(nr * SZ_64K, res->start);
> - else
> + if (res->flags & IORESOURCE_IO) {
> + phys_addr_t io_start = pci_pio_to_address(res->start);
> + pci_ioremap_io(nr * SZ_64K, io_start);
> + } else
> pci_add_resource(&sys->resources, res);
> }
> pci_add_resource(&sys->resources, &pcie->busn);
> @@ -935,8 +942,10 @@ static int rcar_pcie_probe(struct platform_device *pdev)
> }
>
> for_each_of_pci_range(&parser, &range) {
> - of_pci_range_to_resource(&range, pdev->dev.of_node,
> + err = of_pci_range_to_resource(&range, pdev->dev.of_node,
> &pcie->res[win++]);
> + if (err < 0)
> + return err;
>
> if (win > RCAR_PCI_MAX_RESOURCES)
> break;
> diff --git a/include/linux/of_address.h b/include/linux/of_address.h
> index fa20aa15463d..7ebb877b07c2 100644
> --- a/include/linux/of_address.h
> +++ b/include/linux/of_address.h
> @@ -129,9 +129,9 @@ extern const __be32 *of_get_pci_address(struct device_node *dev, int bar_no,
> u64 *size, unsigned int *flags);
> extern int of_pci_address_to_resource(struct device_node *dev, int bar,
> struct resource *r);
> -extern void of_pci_range_to_resource(struct of_pci_range *range,
> - struct device_node *np,
> - struct resource *res);
> +extern int of_pci_range_to_resource(struct of_pci_range *range,
> + struct device_node *np,
> + struct resource *res);
> #else /* CONFIG_OF_ADDRESS && CONFIG_PCI */
> static inline int of_pci_address_to_resource(struct device_node *dev, int bar,
> struct resource *r)
> --
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Next message: Bjorn Helgaas: "Re: [PATCH v12 05/12] PCI: OF: Fix the conversion of IO ranges into IO resources."
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