Re: [PATCH 1/2] PCI: altera: Fix configuration type based on secondary number

From: Lorenzo Pieralisi
Date: Thu May 30 2019 - 11:29:30 EST


On Fri, May 24, 2019 at 02:07:25PM +0800, Ley Foon Tan wrote:
> This fix issue when access config from PCIe switch.
>
> Stratix 10 PCIe controller does not support Type 1 to Type 0 conversion
> as previous version (V1) does.
>
> The PCIe controller need to send Type 0 config TLP if the targeting bus
> matches with the secondary bus number, which is when the TLP is targeting
> the immediate device on the link.
>
> The PCIe controller send Type 1 config TLP if the targeting bus is
> larger than the secondary bus, which is when the TLP is targeting the
> device not immediate on the link.
>
> Signed-off-by: Ley Foon Tan <ley.foon.tan@xxxxxxxxx>
> ---
> drivers/pci/controller/pcie-altera.c | 22 ++++++++++++++++++++--
> 1 file changed, 20 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/pci/controller/pcie-altera.c b/drivers/pci/controller/pcie-altera.c
> index 27222071ace7..047bcc214f9b 100644
> --- a/drivers/pci/controller/pcie-altera.c
> +++ b/drivers/pci/controller/pcie-altera.c
> @@ -44,6 +44,8 @@
> #define S10_RP_RXCPL_STATUS 0x200C
> #define S10_RP_CFG_ADDR(pcie, reg) \
> (((pcie)->hip_base) + (reg) + (1 << 20))
> +#define S10_RP_SECONDARY(pcie) \
> + readb(S10_RP_CFG_ADDR(pcie, PCI_SECONDARY_BUS))
>
> /* TLP configuration type 0 and 1 */
> #define TLP_FMTTYPE_CFGRD0 0x04 /* Configuration Read Type 0 */
> @@ -63,6 +65,14 @@
> ((((bus == pcie->root_bus_nr) ? pcie->pcie_data->cfgwr0 \
> : pcie->pcie_data->cfgwr1) << 24) | \
> TLP_PAYLOAD_SIZE)
> +#define S10_TLP_CFGRD_DW0(pcie, bus) \
> + (((((bus) > S10_RP_SECONDARY(pcie)) ? pcie->pcie_data->cfgrd0 \
> + : pcie->pcie_data->cfgrd1) << 24) | \
> + TLP_PAYLOAD_SIZE)
> +#define S10_TLP_CFGWR_DW0(pcie, bus) \
> + (((((bus) > S10_RP_SECONDARY(pcie)) ? pcie->pcie_data->cfgwr0 \
> + : pcie->pcie_data->cfgwr1) << 24) | \
> + TLP_PAYLOAD_SIZE)
> #define TLP_CFG_DW1(pcie, tag, be) \
> (((TLP_REQ_ID(pcie->root_bus_nr, RP_DEVFN)) << 16) | (tag << 8) | (be))
> #define TLP_CFG_DW2(bus, devfn, offset) \
> @@ -327,7 +337,11 @@ static int tlp_cfg_dword_read(struct altera_pcie *pcie, u8 bus, u32 devfn,
> {
> u32 headers[TLP_HDR_SIZE];
>
> - headers[0] = TLP_CFGRD_DW0(pcie, bus);
> + if (pcie->pcie_data->version == ALTERA_PCIE_V1)
> + headers[0] = TLP_CFGRD_DW0(pcie, bus);
> + else
> + headers[0] = S10_TLP_CFGRD_DW0(pcie, bus);
> +
> headers[1] = TLP_CFG_DW1(pcie, TLP_READ_TAG, byte_en);
> headers[2] = TLP_CFG_DW2(bus, devfn, where);
>
> @@ -342,7 +356,11 @@ static int tlp_cfg_dword_write(struct altera_pcie *pcie, u8 bus, u32 devfn,
> u32 headers[TLP_HDR_SIZE];
> int ret;
>
> - headers[0] = TLP_CFGWR_DW0(pcie, bus);
> + if (pcie->pcie_data->version == ALTERA_PCIE_V1)
> + headers[0] = TLP_CFGWR_DW0(pcie, bus);
> + else
> + headers[0] = S10_TLP_CFGWR_DW0(pcie, bus);
> +

Why don't you rewrite all these macros as an eg:

static inline u32 get_tlp_header()
{}

where you can also handle the version and everything needed to
detect what header should be set-up ?

Lorenzo

> headers[1] = TLP_CFG_DW1(pcie, TLP_WRITE_TAG, byte_en);
> headers[2] = TLP_CFG_DW2(bus, devfn, where);
>
> --
> 2.19.0
>