It is confusing to have two sets of functions to read/write registers, some with csr_readl()/csr_writel(), while others with read_paged_register()/write_paged_register().
In the register space the lower 3KB of 4KB PCIe configure space can be accessed directly and higher 1KB through a simple paging mechanism. Unify the register accessors in csr_readl() and csr_writel() by comparing the register offset with page access boundary 3KB in the accessor internal so that the paging mechanism is hidden behind the csr_read()/write() common function calls. Signed-off-by: Hou Zhiqiang <zhiqiang....@nxp.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieral...@arm.com> Reviewed-by: Minghuan Lian <minghuan.l...@nxp.com> Reviewed-by: Subrahmanya Lingappa <l.subrahma...@mobiveil.co.in> --- V6: - No change. drivers/pci/controller/pcie-mobiveil.c | 179 ++++++++++++++++++++++---------- 1 files changed, 124 insertions(+), 55 deletions(-) diff --git a/drivers/pci/controller/pcie-mobiveil.c b/drivers/pci/controller/pcie-mobiveil.c index 77052a0..d55c7e7 100644 --- a/drivers/pci/controller/pcie-mobiveil.c +++ b/drivers/pci/controller/pcie-mobiveil.c @@ -47,7 +47,6 @@ #define PAGE_SEL_SHIFT 13 #define PAGE_SEL_MASK 0x3f #define PAGE_LO_MASK 0x3ff -#define PAGE_SEL_EN 0xc00 #define PAGE_SEL_OFFSET_SHIFT 10 #define PAB_AXI_PIO_CTRL 0x0840 @@ -117,6 +116,12 @@ #define LINK_WAIT_MIN 90000 #define LINK_WAIT_MAX 100000 +#define PAGED_ADDR_BNDRY 0xc00 +#define OFFSET_TO_PAGE_ADDR(off) \ + ((off & PAGE_LO_MASK) | PAGED_ADDR_BNDRY) +#define OFFSET_TO_PAGE_IDX(off) \ + ((off >> PAGE_SEL_OFFSET_SHIFT) & PAGE_SEL_MASK) + struct mobiveil_msi { /* MSI information */ struct mutex lock; /* protect bitmap variable */ struct irq_domain *msi_domain; @@ -145,15 +150,119 @@ struct mobiveil_pcie { struct mobiveil_msi msi; }; -static inline void csr_writel(struct mobiveil_pcie *pcie, const u32 value, - const u32 reg) +/* + * mobiveil_pcie_sel_page - routine to access paged register + * + * Registers whose address greater than PAGED_ADDR_BNDRY (0xc00) are paged, + * for this scheme to work extracted higher 6 bits of the offset will be + * written to pg_sel field of PAB_CTRL register and rest of the lower 10 + * bits enabled with PAGED_ADDR_BNDRY are used as offset of the register. + */ +static void mobiveil_pcie_sel_page(struct mobiveil_pcie *pcie, u8 pg_idx) { - writel_relaxed(value, pcie->csr_axi_slave_base + reg); + u32 val; + + val = readl(pcie->csr_axi_slave_base + PAB_CTRL); + val &= ~(PAGE_SEL_MASK << PAGE_SEL_SHIFT); + val |= (pg_idx & PAGE_SEL_MASK) << PAGE_SEL_SHIFT; + + writel(val, pcie->csr_axi_slave_base + PAB_CTRL); } -static inline u32 csr_readl(struct mobiveil_pcie *pcie, const u32 reg) +static void *mobiveil_pcie_comp_addr(struct mobiveil_pcie *pcie, u32 off) { - return readl_relaxed(pcie->csr_axi_slave_base + reg); + if (off < PAGED_ADDR_BNDRY) { + /* For directly accessed registers, clear the pg_sel field */ + mobiveil_pcie_sel_page(pcie, 0); + return pcie->csr_axi_slave_base + off; + } + + mobiveil_pcie_sel_page(pcie, OFFSET_TO_PAGE_IDX(off)); + return pcie->csr_axi_slave_base + OFFSET_TO_PAGE_ADDR(off); +} + +static int mobiveil_pcie_read(void __iomem *addr, int size, u32 *val) +{ + if ((uintptr_t)addr & (size - 1)) { + *val = 0; + return PCIBIOS_BAD_REGISTER_NUMBER; + } + + switch (size) { + case 4: + *val = readl(addr); + break; + case 2: + *val = readw(addr); + break; + case 1: + *val = readb(addr); + break; + default: + *val = 0; + return PCIBIOS_BAD_REGISTER_NUMBER; + } + + return PCIBIOS_SUCCESSFUL; +} + +static int mobiveil_pcie_write(void __iomem *addr, int size, u32 val) +{ + if ((uintptr_t)addr & (size - 1)) + return PCIBIOS_BAD_REGISTER_NUMBER; + + switch (size) { + case 4: + writel(val, addr); + break; + case 2: + writew(val, addr); + break; + case 1: + writeb(val, addr); + break; + default: + return PCIBIOS_BAD_REGISTER_NUMBER; + } + + return PCIBIOS_SUCCESSFUL; +} + +static u32 csr_read(struct mobiveil_pcie *pcie, u32 off, size_t size) +{ + void *addr; + u32 val; + int ret; + + addr = mobiveil_pcie_comp_addr(pcie, off); + + ret = mobiveil_pcie_read(addr, size, &val); + if (ret) + dev_err(&pcie->pdev->dev, "read CSR address failed\n"); + + return val; +} + +static void csr_write(struct mobiveil_pcie *pcie, u32 val, u32 off, size_t size) +{ + void *addr; + int ret; + + addr = mobiveil_pcie_comp_addr(pcie, off); + + ret = mobiveil_pcie_write(addr, size, val); + if (ret) + dev_err(&pcie->pdev->dev, "write CSR address failed\n"); +} + +static u32 csr_readl(struct mobiveil_pcie *pcie, u32 off) +{ + return csr_read(pcie, off, 0x4); +} + +static void csr_writel(struct mobiveil_pcie *pcie, u32 val, u32 off) +{ + csr_write(pcie, val, off, 0x4); } static bool mobiveil_pcie_link_up(struct mobiveil_pcie *pcie) @@ -342,45 +451,6 @@ static int mobiveil_pcie_parse_dt(struct mobiveil_pcie *pcie) return 0; } -/* - * select_paged_register - routine to access paged register of root complex - * - * registers of RC are paged, for this scheme to work - * extracted higher 6 bits of the offset will be written to pg_sel - * field of PAB_CTRL register and rest of the lower 10 bits enabled with - * PAGE_SEL_EN are used as offset of the register. - */ -static void select_paged_register(struct mobiveil_pcie *pcie, u32 offset) -{ - int pab_ctrl_dw, pg_sel; - - /* clear pg_sel field */ - pab_ctrl_dw = csr_readl(pcie, PAB_CTRL); - pab_ctrl_dw = (pab_ctrl_dw & ~(PAGE_SEL_MASK << PAGE_SEL_SHIFT)); - - /* set pg_sel field */ - pg_sel = (offset >> PAGE_SEL_OFFSET_SHIFT) & PAGE_SEL_MASK; - pab_ctrl_dw |= ((pg_sel << PAGE_SEL_SHIFT)); - csr_writel(pcie, pab_ctrl_dw, PAB_CTRL); -} - -static void write_paged_register(struct mobiveil_pcie *pcie, - u32 val, u32 offset) -{ - u32 off = (offset & PAGE_LO_MASK) | PAGE_SEL_EN; - - select_paged_register(pcie, offset); - csr_writel(pcie, val, off); -} - -static u32 read_paged_register(struct mobiveil_pcie *pcie, u32 offset) -{ - u32 off = (offset & PAGE_LO_MASK) | PAGE_SEL_EN; - - select_paged_register(pcie, offset); - return csr_readl(pcie, off); -} - static void program_ib_windows(struct mobiveil_pcie *pcie, int win_num, int pci_addr, u32 type, u64 size) { @@ -397,19 +467,19 @@ static void program_ib_windows(struct mobiveil_pcie *pcie, int win_num, pio_ctrl_val = csr_readl(pcie, PAB_PEX_PIO_CTRL); csr_writel(pcie, pio_ctrl_val | (1 << PIO_ENABLE_SHIFT), PAB_PEX_PIO_CTRL); - amap_ctrl_dw = read_paged_register(pcie, PAB_PEX_AMAP_CTRL(win_num)); + amap_ctrl_dw = csr_readl(pcie, PAB_PEX_AMAP_CTRL(win_num)); amap_ctrl_dw = (amap_ctrl_dw | (type << AMAP_CTRL_TYPE_SHIFT)); amap_ctrl_dw = (amap_ctrl_dw | (1 << AMAP_CTRL_EN_SHIFT)); - write_paged_register(pcie, amap_ctrl_dw | lower_32_bits(size64), - PAB_PEX_AMAP_CTRL(win_num)); + csr_writel(pcie, amap_ctrl_dw | lower_32_bits(size64), + PAB_PEX_AMAP_CTRL(win_num)); - write_paged_register(pcie, upper_32_bits(size64), - PAB_EXT_PEX_AMAP_SIZEN(win_num)); + csr_writel(pcie, upper_32_bits(size64), + PAB_EXT_PEX_AMAP_SIZEN(win_num)); - write_paged_register(pcie, pci_addr, PAB_PEX_AMAP_AXI_WIN(win_num)); - write_paged_register(pcie, pci_addr, PAB_PEX_AMAP_PEX_WIN_L(win_num)); - write_paged_register(pcie, 0, PAB_PEX_AMAP_PEX_WIN_H(win_num)); + csr_writel(pcie, pci_addr, PAB_PEX_AMAP_AXI_WIN(win_num)); + csr_writel(pcie, pci_addr, PAB_PEX_AMAP_PEX_WIN_L(win_num)); + csr_writel(pcie, 0, PAB_PEX_AMAP_PEX_WIN_H(win_num)); } /* @@ -437,8 +507,7 @@ static void program_ob_windows(struct mobiveil_pcie *pcie, int win_num, csr_writel(pcie, 1 << WIN_ENABLE_SHIFT | type << WIN_TYPE_SHIFT | lower_32_bits(size64), PAB_AXI_AMAP_CTRL(win_num)); - write_paged_register(pcie, upper_32_bits(size64), - PAB_EXT_AXI_AMAP_SIZE(win_num)); + csr_writel(pcie, upper_32_bits(size64), PAB_EXT_AXI_AMAP_SIZE(win_num)); /* * program AXI window base with appropriate value in -- 1.7.1