From 6d6b05e3d5337f645a411cdf72f1a083e495acb8 Mon Sep 17 00:00:00 2001 From: Stephen Warren Date: Fri, 30 Nov 2018 11:37:19 -0700 Subject: [PATCH] PCI: dwc: Don't hard-code DBI/ATU offset The DWC PCIe core contains various separate register spaces: DBI, DBI2, ATU, DMA, etc. The relationship between the addresses of these register spaces is entirely determined by the implementation of the IP block, not by the IP block design itself. Hence, the DWC driver must not make assumptions that one register space can be accessed at a fixed offset from any other register space. To avoid such assumptions, introduce an explicit/separate register pointer for the ATU register space. In particular, the current assumption is not valid for NVIDIA's T194 SoC. The ATU register space is only used on systems that require unrolled ATU access. This property is detected at run-time for host controllers, and when this is detected, this patch provides a default value for atu_base that matches the previous assumption re: register layout. An alternative would be to update all drivers for HW that requires unrolled access to explicitly set atu_base. However, it's hard to tell which drivers would require atu_base to be set. The unrolled property is not detected for endpoint systems, and so any endpoint driver that requires unrolled access must explicitly set the iatu_unroll_enabled flag (none do at present), and so a check is added to require the driver to also set atu_base while at it. Signed-off-by: Stephen Warren Signed-off-by: Lorenzo Pieralisi Acked-by: Gustavo Pimentel Acked-by: Vidya Sagar --- drivers/pci/controller/dwc/pcie-designware-ep.c | 4 ++++ drivers/pci/controller/dwc/pcie-designware-host.c | 3 +++ drivers/pci/controller/dwc/pcie-designware.c | 8 +++---- drivers/pci/controller/dwc/pcie-designware.h | 28 +++++++++++++++++++---- 4 files changed, 35 insertions(+), 8 deletions(-) diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c index 1e7b022..8802103 100644 --- a/drivers/pci/controller/dwc/pcie-designware-ep.c +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c @@ -504,6 +504,10 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep) dev_err(dev, "dbi_base/dbi_base2 is not populated\n"); return -EINVAL; } + if (pci->iatu_unroll_enabled && !pci->atu_base) { + dev_err(dev, "atu_base is not populated\n"); + return -EINVAL; + } ret = of_property_read_u32(np, "num-ib-windows", &ep->num_ib_windows); if (ret < 0) { diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c index 29a0575..692dd1b 100644 --- a/drivers/pci/controller/dwc/pcie-designware-host.c +++ b/drivers/pci/controller/dwc/pcie-designware-host.c @@ -699,6 +699,9 @@ void dw_pcie_setup_rc(struct pcie_port *pp) dev_dbg(pci->dev, "iATU unroll: %s\n", pci->iatu_unroll_enabled ? "enabled" : "disabled"); + if (pci->iatu_unroll_enabled && !pci->atu_base) + pci->atu_base = pci->dbi_base + DEFAULT_DBI_ATU_OFFSET; + dw_pcie_prog_outbound_atu(pci, PCIE_ATU_REGION_INDEX0, PCIE_ATU_TYPE_MEM, pp->mem_base, pp->mem_bus_addr, pp->mem_size); diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c index 2153956..93ef8c3 100644 --- a/drivers/pci/controller/dwc/pcie-designware.c +++ b/drivers/pci/controller/dwc/pcie-designware.c @@ -93,7 +93,7 @@ static u32 dw_pcie_readl_ob_unroll(struct dw_pcie *pci, u32 index, u32 reg) { u32 offset = PCIE_GET_ATU_OUTB_UNR_REG_OFFSET(index); - return dw_pcie_readl_dbi(pci, offset + reg); + return dw_pcie_readl_atu(pci, offset + reg); } static void dw_pcie_writel_ob_unroll(struct dw_pcie *pci, u32 index, u32 reg, @@ -101,7 +101,7 @@ static void dw_pcie_writel_ob_unroll(struct dw_pcie *pci, u32 index, u32 reg, { u32 offset = PCIE_GET_ATU_OUTB_UNR_REG_OFFSET(index); - dw_pcie_writel_dbi(pci, offset + reg, val); + dw_pcie_writel_atu(pci, offset + reg, val); } static void dw_pcie_prog_outbound_atu_unroll(struct dw_pcie *pci, int index, @@ -187,7 +187,7 @@ static u32 dw_pcie_readl_ib_unroll(struct dw_pcie *pci, u32 index, u32 reg) { u32 offset = PCIE_GET_ATU_INB_UNR_REG_OFFSET(index); - return dw_pcie_readl_dbi(pci, offset + reg); + return dw_pcie_readl_atu(pci, offset + reg); } static void dw_pcie_writel_ib_unroll(struct dw_pcie *pci, u32 index, u32 reg, @@ -195,7 +195,7 @@ static void dw_pcie_writel_ib_unroll(struct dw_pcie *pci, u32 index, u32 reg, { u32 offset = PCIE_GET_ATU_INB_UNR_REG_OFFSET(index); - dw_pcie_writel_dbi(pci, offset + reg, val); + dw_pcie_writel_atu(pci, offset + reg, val); } static int dw_pcie_prog_inbound_atu_unroll(struct dw_pcie *pci, int index, diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h index 0989d88..9943d8c 100644 --- a/drivers/pci/controller/dwc/pcie-designware.h +++ b/drivers/pci/controller/dwc/pcie-designware.h @@ -92,12 +92,20 @@ #define PCIE_ATU_UNR_LOWER_TARGET 0x14 #define PCIE_ATU_UNR_UPPER_TARGET 0x18 +/* + * The default address offset between dbi_base and atu_base. Root controller + * drivers are not required to initialize atu_base if the offset matches this + * default; the driver core automatically derives atu_base from dbi_base using + * this offset, if atu_base not set. + */ +#define DEFAULT_DBI_ATU_OFFSET (0x3 << 20) + /* Register address builder */ -#define PCIE_GET_ATU_OUTB_UNR_REG_OFFSET(region) \ - ((0x3 << 20) | ((region) << 9)) +#define PCIE_GET_ATU_OUTB_UNR_REG_OFFSET(region) \ + ((region) << 9) -#define PCIE_GET_ATU_INB_UNR_REG_OFFSET(region) \ - ((0x3 << 20) | ((region) << 9) | (0x1 << 8)) +#define PCIE_GET_ATU_INB_UNR_REG_OFFSET(region) \ + (((region) << 9) | (0x1 << 8)) #define MAX_MSI_IRQS 256 #define MAX_MSI_IRQS_PER_CTRL 32 @@ -219,6 +227,8 @@ struct dw_pcie { struct device *dev; void __iomem *dbi_base; void __iomem *dbi_base2; + /* Used when iatu_unroll_enabled is true */ + void __iomem *atu_base; u32 num_viewport; u8 iatu_unroll_enabled; struct pcie_port pp; @@ -289,6 +299,16 @@ static inline u32 dw_pcie_readl_dbi2(struct dw_pcie *pci, u32 reg) return __dw_pcie_read_dbi(pci, pci->dbi_base2, reg, 0x4); } +static inline void dw_pcie_writel_atu(struct dw_pcie *pci, u32 reg, u32 val) +{ + __dw_pcie_write_dbi(pci, pci->atu_base, reg, 0x4, val); +} + +static inline u32 dw_pcie_readl_atu(struct dw_pcie *pci, u32 reg) +{ + return __dw_pcie_read_dbi(pci, pci->atu_base, reg, 0x4); +} + static inline void dw_pcie_dbi_ro_wr_en(struct dw_pcie *pci) { u32 reg; -- 2.7.4