diff options
Diffstat (limited to 'drivers/pci/cadence/pcie-cadence.c')
| -rw-r--r-- | drivers/pci/cadence/pcie-cadence.c | 126 |
1 files changed, 126 insertions, 0 deletions
diff --git a/drivers/pci/cadence/pcie-cadence.c b/drivers/pci/cadence/pcie-cadence.c new file mode 100644 index 000000000000..138d113eb45d --- /dev/null +++ b/drivers/pci/cadence/pcie-cadence.c @@ -0,0 +1,126 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2017 Cadence +// Cadence PCIe controller driver. +// Author: Cyrille Pitchen <cyrille.pitchen@free-electrons.com> + +#include <linux/kernel.h> + +#include "pcie-cadence.h" + +void cdns_pcie_set_outbound_region(struct cdns_pcie *pcie, u8 fn, + u32 r, bool is_io, + u64 cpu_addr, u64 pci_addr, size_t size) +{ + /* + * roundup_pow_of_two() returns an unsigned long, which is not suited + * for 64bit values. + */ + u64 sz = 1ULL << fls64(size - 1); + int nbits = ilog2(sz); + u32 addr0, addr1, desc0, desc1; + + if (nbits < 8) + nbits = 8; + + /* Set the PCI address */ + addr0 = CDNS_PCIE_AT_OB_REGION_PCI_ADDR0_NBITS(nbits) | + (lower_32_bits(pci_addr) & GENMASK(31, 8)); + addr1 = upper_32_bits(pci_addr); + + cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_PCI_ADDR0(r), addr0); + cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_PCI_ADDR1(r), addr1); + + /* Set the PCIe header descriptor */ + if (is_io) + desc0 = CDNS_PCIE_AT_OB_REGION_DESC0_TYPE_IO; + else + desc0 = CDNS_PCIE_AT_OB_REGION_DESC0_TYPE_MEM; + desc1 = 0; + + /* + * Whatever Bit [23] is set or not inside DESC0 register of the outbound + * PCIe descriptor, the PCI function number must be set into + * Bits [26:24] of DESC0 anyway. + * + * In Root Complex mode, the function number is always 0 but in Endpoint + * mode, the PCIe controller may support more than one function. This + * function number needs to be set properly into the outbound PCIe + * descriptor. + * + * Besides, setting Bit [23] is mandatory when in Root Complex mode: + * then the driver must provide the bus, resp. device, number in + * Bits [7:0] of DESC1, resp. Bits[31:27] of DESC0. Like the function + * number, the device number is always 0 in Root Complex mode. + * + * However when in Endpoint mode, we can clear Bit [23] of DESC0, hence + * the PCIe controller will use the captured values for the bus and + * device numbers. + */ + if (pcie->is_rc) { + /* The device and function numbers are always 0. */ + desc0 |= CDNS_PCIE_AT_OB_REGION_DESC0_HARDCODED_RID | + CDNS_PCIE_AT_OB_REGION_DESC0_DEVFN(0); + desc1 |= CDNS_PCIE_AT_OB_REGION_DESC1_BUS(pcie->bus); + } else { + /* + * Use captured values for bus and device numbers but still + * need to set the function number. + */ + desc0 |= CDNS_PCIE_AT_OB_REGION_DESC0_DEVFN(fn); + } + + cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_DESC0(r), desc0); + cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_DESC1(r), desc1); + + /* Set the CPU address */ + cpu_addr -= pcie->mem_res->start; + addr0 = CDNS_PCIE_AT_OB_REGION_CPU_ADDR0_NBITS(nbits) | + (lower_32_bits(cpu_addr) & GENMASK(31, 8)); + addr1 = upper_32_bits(cpu_addr); + + cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_CPU_ADDR0(r), addr0); + cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_CPU_ADDR1(r), addr1); +} + +void cdns_pcie_set_outbound_region_for_normal_msg(struct cdns_pcie *pcie, u8 fn, + u32 r, u64 cpu_addr) +{ + u32 addr0, addr1, desc0, desc1; + + desc0 = CDNS_PCIE_AT_OB_REGION_DESC0_TYPE_NORMAL_MSG; + desc1 = 0; + + /* See cdns_pcie_set_outbound_region() comments above. */ + if (pcie->is_rc) { + desc0 |= CDNS_PCIE_AT_OB_REGION_DESC0_HARDCODED_RID | + CDNS_PCIE_AT_OB_REGION_DESC0_DEVFN(0); + desc1 |= CDNS_PCIE_AT_OB_REGION_DESC1_BUS(pcie->bus); + } else { + desc0 |= CDNS_PCIE_AT_OB_REGION_DESC0_DEVFN(fn); + } + + /* Set the CPU address */ + cpu_addr -= pcie->mem_res->start; + addr0 = CDNS_PCIE_AT_OB_REGION_CPU_ADDR0_NBITS(17) | + (lower_32_bits(cpu_addr) & GENMASK(31, 8)); + addr1 = upper_32_bits(cpu_addr); + + cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_PCI_ADDR0(r), 0); + cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_PCI_ADDR1(r), 0); + cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_DESC0(r), desc0); + cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_DESC1(r), desc1); + cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_CPU_ADDR0(r), addr0); + cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_CPU_ADDR1(r), addr1); +} + +void cdns_pcie_reset_outbound_region(struct cdns_pcie *pcie, u32 r) +{ + cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_PCI_ADDR0(r), 0); + cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_PCI_ADDR1(r), 0); + + cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_DESC0(r), 0); + cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_DESC1(r), 0); + + cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_CPU_ADDR0(r), 0); + cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_CPU_ADDR1(r), 0); +} |