Re: [PATCH v11 04/10] PCI: OF: Fix the conversion of IO ranges into IO resources.

[Rob Herring <robherring2@gmail.com>]

On 09/17/2014 08:30 PM, 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.
> 
> In the process move the function into drivers/of/address.c as it now
> depends on pci_address_to_pio() code and make it return an error code.
> Also fix all the drivers that depend on the old behaviour by fetching
> the CPU physical address based on the port number.
> 
> Cc: Grant Likely <grant.likely@linaro.org>
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: Arnd Bergmann <arnd@arndb.de>
> Cc: Linus Walleij <linus.walleij@linaro.org>
> Cc: Thierry Reding <thierry.reding@gmail.com>
> Cc: Simon Horman <horms@verge.net.au>
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>

A few minor things below.

> ---
>  arch/arm/mach-integrator/pci_v3.c | 23 ++++++++++----------
>  drivers/of/address.c              | 46 +++++++++++++++++++++++++++++++++++++++
>  drivers/pci/host/pci-tegra.c      | 10 ++++++---
>  drivers/pci/host/pcie-rcar.c      | 21 +++++++++++++-----
>  include/linux/of_address.h        | 13 ++---------
>  5 files changed, 82 insertions(+), 31 deletions(-)
> 
> diff --git a/arch/arm/mach-integrator/pci_v3.c b/arch/arm/mach-integrator/pci_v3.c
> index 05e1f73..3321e1b 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 -EINVAL;

You should return ret rather than potentially changing the return value.

> +		}
>  	}
>  
>  	pci_v3.map_irq = of_irq_parse_and_map_pci;
> diff --git a/drivers/of/address.c b/drivers/of/address.c
> index 2373a92..ff10b64 100644
> --- a/drivers/of/address.c
> +++ b/drivers/of/address.c
> @@ -947,3 +947,49 @@ bool of_dma_is_coherent(struct device_node *np)
>  	return false;
>  }
>  EXPORT_SYMBOL_GPL(of_dma_is_coherent);
> +
> +/*
> + * 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->parent = res->child = res->sibling = NULL;
> +	res->name = np->full_name;
> +
> +	if (res->flags & IORESOURCE_IO) {
> +		unsigned long port = -1;

Assigning a signed value to unsigned...

Does port need to be 64-bit on 64-bit hosts?

> +		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;
> +}
> diff --git a/drivers/pci/host/pci-tegra.c b/drivers/pci/host/pci-tegra.c
> index 0fb0fdb..946935d 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 4884ee5..61158e0 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 f8cc7da..c9d70deb 100644
> --- a/include/linux/of_address.h
> +++ b/include/linux/of_address.h
> @@ -23,17 +23,8 @@ 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;
> -}
> -
> +extern int of_pci_range_to_resource(struct of_pci_range *range,
> +		struct device_node *np, struct resource *res);

We probably need an empty version of this now for !OF_ADDRESS.

Rob