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

[Kishon Vijay Abraham I <kishon@ti.com>]

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?

Cheers
Kishon
> 
> Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
> Cc: Bjorn Helgaas <bhelgaas@google.com>
> Cc: Mohit Kumar <mohit.kumar@st.com>
> Cc: Jingoo Han <jg1.han@samsung.com>
> Cc: Marek Vasut <marex@denx.de>
> Cc: Arnd Bergmann <arnd@arndb.de>
> Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
> ---
>  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;
>