Re: [PATCH v1 7/9] PCI: microchip: Partition outbound address translation

Conor Dooley
2022-11-23T22:45:11Z

On Wed, Nov 16, 2022 at 01:55:02PM +0000, daire.mcnamara@microchip.com wrote:
> From: Daire McNamara <daire.mcnamara@microchip.com>
>
> On Microchip PolarFire SoC the PCIe rootport is behind a set of fabric
> inter connect (fic) busses that encapsulate busses like ABP/AHP and
> AXI-M. Depending on which fic(s) the rootport is wired through to cpu
> space, the rootport driver needs to take account of the address
> translation done by a parent (e.g. fabric) node before setting up its
> own outbound address translation tables to config space and attached
> devices.
>
> Parse the range properties to determine how much address translation
> needs to be done in the rootport.
>
> Signed-off-by: Daire McNamara <daire.mcnamara@microchip.com>
> Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
> ---
> drivers/pci/controller/pcie-microchip-host.c | 109 +++++++++++++++----
> 1 file changed, 86 insertions(+), 23 deletions(-)
>
> diff --git a/drivers/pci/controller/pcie-microchip-host.c b/drivers/pci/controller/pcie-microchip-host.c
> index 73856647f321..62f8c5edfd0e 100644
> --- a/drivers/pci/controller/pcie-microchip-host.c
> +++ b/drivers/pci/controller/pcie-microchip-host.c
> @@ -85,27 +85,42 @@
> #define IMSI_ADDR 0x190
> #define ISTATUS_MSI 0x194
>
> +#define ATR_WINDOW_DESC_SIZE 32
> +#define ATR_PCIE_ATR_SIZE 0x25
> +#define ATR_SIZE_SHIFT 1
> +#define ATR_IMPL_ENABLE 1
> +
> /* PCIe Master table init defines */
> #define ATR0_PCIE_WIN0_SRCADDR_PARAM 0x600u
> -#define ATR0_PCIE_ATR_SIZE 0x25
> -#define ATR0_PCIE_ATR_SIZE_SHIFT 1
> #define ATR0_PCIE_WIN0_SRC_ADDR 0x604u
> #define ATR0_PCIE_WIN0_TRSL_ADDR_LSB 0x608u
> #define ATR0_PCIE_WIN0_TRSL_ADDR_UDW 0x60cu
> #define ATR0_PCIE_WIN0_TRSL_PARAM 0x610u
>
> +enum {
> + TRSL_ID_PCIE_TXRX = 0,
> + TRSL_ID_PCIE_CONFIG = 1,
> + TRSL_ID_AXI4_LITE_MASTER = 2,
> + TRSL_ID_AXI4_MASTER_0 = 4,

My enum-fu is pretty bad, but can't we just drop all the numbers here
apart from 4 & the ordering will still be correct?
Maybe that's not ideal from a readability point of view though?

Otherwise, with whatever complaints LKP had & Bjorn's/my previous nits
fixed:
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>

Thanks,
Conor.

> + TRSL_ID_AXI4_MASTER_1 = 5,
> + TRSL_ID_AXI4_MASTER_2 = 6,
> + TRSL_ID_AXI4_MASTER_3 = 7,
> + TRSL_ID_AXI4_STREAM_0 = 8,
> + TRSL_ID_AXI4_STREAM_1 = 9,
> + TRSL_ID_AXI4_STREAM_2 = 10,
> + TRSL_ID_AXI4_STREAM_3 = 11,
> + TRSL_ID_INTERNAL_BRIDGE_REGISTERS = 12,
> +};
> +
> +#define ATR0_PCIE_WIN0_TRSL_MASK_LSB 0x618u
> +#define ATR0_PCIE_WIN0_TRSL_MASK_UDW 0x61cu
> +
> /* PCIe AXI slave table init defines */
> #define ATR0_AXI4_SLV0_SRCADDR_PARAM 0x800u
> -#define ATR_SIZE_SHIFT 1
> -#define ATR_IMPL_ENABLE 1
> #define ATR0_AXI4_SLV0_SRC_ADDR 0x804u
> #define ATR0_AXI4_SLV0_TRSL_ADDR_LSB 0x808u
> #define ATR0_AXI4_SLV0_TRSL_ADDR_UDW 0x80cu
> #define ATR0_AXI4_SLV0_TRSL_PARAM 0x810u
> -#define PCIE_TX_RX_INTERFACE 0x00000000u
> -#define PCIE_CONFIG_INTERFACE 0x00000001u
> -
> -#define ATR_ENTRY_SIZE 32
>
> /* PCIe Controller Phy Regs */
> #define SEC_ERROR_EVENT_CNT 0x20
> @@ -268,6 +283,7 @@ struct mc_pcie {
> struct irq_domain *event_domain;
> raw_spinlock_t lock;
> struct mc_msi msi;
> + u64 outbound_range_offset;
> };
>
> struct cause {
> @@ -928,36 +944,36 @@ static void mc_pcie_setup_window(void __iomem *bridge_base_addr, u32 index,
> phys_addr_t axi_addr, phys_addr_t pci_addr,
> size_t size)
> {
> - u32 atr_sz = ilog2(size) - 1;
> + u32 atr_size = ilog2(size) - 1;
> u32 val;
>
> if (index == 0)
> - val = PCIE_CONFIG_INTERFACE;
> + val = TRSL_ID_PCIE_CONFIG;
> else
> - val = PCIE_TX_RX_INTERFACE;
> + val = TRSL_ID_PCIE_TXRX;
>
> - writel(val, bridge_base_addr + (index * ATR_ENTRY_SIZE) +
> + writel(val, bridge_base_addr + (index * ATR_WINDOW_DESC_SIZE) +
> ATR0_AXI4_SLV0_TRSL_PARAM);
>
> - val = lower_32_bits(axi_addr) | (atr_sz << ATR_SIZE_SHIFT) |
> + val = lower_32_bits(axi_addr) | (atr_size << ATR_SIZE_SHIFT) |
> ATR_IMPL_ENABLE;
> - writel(val, bridge_base_addr + (index * ATR_ENTRY_SIZE) +
> + writel(val, bridge_base_addr + (index * ATR_WINDOW_DESC_SIZE) +
> ATR0_AXI4_SLV0_SRCADDR_PARAM);
>
> val = upper_32_bits(axi_addr);
> - writel(val, bridge_base_addr + (index * ATR_ENTRY_SIZE) +
> + writel(val, bridge_base_addr + (index * ATR_WINDOW_DESC_SIZE) +
> ATR0_AXI4_SLV0_SRC_ADDR);
>
> val = lower_32_bits(pci_addr);
> - writel(val, bridge_base_addr + (index * ATR_ENTRY_SIZE) +
> + writel(val, bridge_base_addr + (index * ATR_WINDOW_DESC_SIZE) +
> ATR0_AXI4_SLV0_TRSL_ADDR_LSB);
>
> val = upper_32_bits(pci_addr);
> - writel(val, bridge_base_addr + (index * ATR_ENTRY_SIZE) +
> + writel(val, bridge_base_addr + (index * ATR_WINDOW_DESC_SIZE) +
> ATR0_AXI4_SLV0_TRSL_ADDR_UDW);
>
> val = readl(bridge_base_addr + ATR0_PCIE_WIN0_SRCADDR_PARAM);
> - val |= (ATR0_PCIE_ATR_SIZE << ATR0_PCIE_ATR_SIZE_SHIFT);
> + val |= (ATR_PCIE_ATR_SIZE << ATR_SIZE_SHIFT);
> writel(val, bridge_base_addr + ATR0_PCIE_WIN0_SRCADDR_PARAM);
> writel(0, bridge_base_addr + ATR0_PCIE_WIN0_SRC_ADDR);
> }
> @@ -970,14 +986,14 @@ static int mc_pcie_setup_windows(struct platform_device *pdev,
> struct pci_host_bridge *bridge = platform_get_drvdata(pdev);
> struct resource_entry *entry;
> u64 pci_addr;
> - u32 index = 1;
> + u32 index = 1; /* window 0 used for config space */
>
> resource_list_for_each_entry(entry, &bridge->windows) {
> if (resource_type(entry->res) == IORESOURCE_MEM) {
> pci_addr = entry->res->start - entry->offset;
> mc_pcie_setup_window(bridge_base_addr, index,
> - entry->res->start, pci_addr,
> - resource_size(entry->res));
> + entry->res->start - port->outbound_range_offset,
> + pci_addr, resource_size(entry->res));
> index++;
> }
> }
> @@ -1093,6 +1109,44 @@ static int mc_init_interrupts(struct platform_device *pdev, struct mc_pcie *port
> return 0;
> }
>
> +static int mc_check_for_parent_range_handling(struct platform_device *pdev, struct mc_pcie *port)
> +{
> + struct device *dev = &pdev->dev;
> + struct device_node *dn = dev->of_node;
> + struct of_range_parser parser;
> + struct of_range range;
> + u64 cpu_addr;
> +
> + /* find any pcie range */
> + if (of_range_parser_init(&parser, dn)) {
> + dev_err(dev, "missing ranges property\n");
> + return -EINVAL;
> + }
> +
> + for_each_of_range(&parser, &range) {
> + cpu_addr = range.cpu_addr;
> + /*
> + * first range is enough - extend if anyone
> + * ever needs more than one fabric interface
> + */
> + break;
> + }
> +
> + /* check for one level up; that is enough */
> + dn = of_get_parent(dn);
> + if (dn) {
> + of_range_parser_init(&parser, dn);
> + for_each_of_range(&parser, &range) {
> + /* find the parent range that contains cpu_addr */
> + if (range.cpu_addr > port->outbound_range_offset &&
> + range.cpu_addr < cpu_addr)
> + port->outbound_range_offset = range.cpu_addr;
> + }
> + }
> +
> + return 0;
> +}
> +
> static int mc_platform_init(struct pci_config_window *cfg)
> {
> struct device *dev = cfg->parent;
> @@ -1101,9 +1155,18 @@ static int mc_platform_init(struct pci_config_window *cfg)
> port->axi_base_addr + MC_PCIE_BRIDGE_ADDR;
> int ret;
>
> + /*
> + * need information about any parent bus that may
> + * be performing some of the outbound address translation
> + * to setup outbound address translation tables later
> + */
> + ret = mc_check_for_parent_range_handling(pdev, port);
> + if (ret)
> + return ret;
> +
> /* Configure address translation table 0 for PCIe config space */
> - mc_pcie_setup_window(bridge_base_addr, 0, cfg->res.start,
> - cfg->res.start,
> + mc_pcie_setup_window(bridge_base_addr, 0, cfg->res.start - port->outbound_range_offset,
> + cfg->res.start - port->outbound_range_offset,
> resource_size(&cfg->res));
>
> /* Need some fixups in config space */
> --
> 2.25.1
>
>
> _______________________________________________
> linux-riscv mailing list
> linux-riscv@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-riscv