[RFT PATCH v2 02/42] drivers: pci: host: iproc: Convert link check to raw PCI config accessors

Lorenzo Pieralisi lorenzo.pieralisi at arm.com
Thu Jun 8 09:36:14 PDT 2017


[dropped rock-chips maintainers, email bounces]

On Thu, Jun 08, 2017 at 08:56:05AM -0700, Ray Jui wrote:
> Hi Lorenzo,
> 
> Thanks, I'll try my best to find time to test this along 15/42 and
> 33/42 patches. Hopefully I can get to that some time next week.
> 
> I have not yet reviewed these patches in details. Do they have
> dependency on other patches to the generic framework code you
> changed?
> 
> If so, is there a repo I can pull them?

I added it in the cover letter but anyway here it is:

git://git.kernel.org/pub/scm/linux/kernel/git/lpieralisi/linux.git pci/pci-fixup-irqs-removal-v2

Thanks for testing it, please let me know.

Thank you !
Lorenzo

> 
> Thanks,
> 
> Ray
> 
> 
> On 6/8/2017 7:13 AM, Lorenzo Pieralisi wrote:
> >Current iproc driver host bridge controller driver requires struct
> >pci_bus to be created in order to carry out PCI link checks with standard
> >PCI config space accessors.
> >
> >This struct pci_bus dependency is fictitious and burdens the driver
> >with unneeded constraints (eg to use separate APIs to create and scan
> >the root bus).
> >
> >Add PCI raw config space accessors to PCIe iproc driver and remove the
> >fictitious struct pci_bus dependency.
> >
> >Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi at arm.com>
> >Cc: Scott Branden <sbranden at broadcom.com>
> >Cc: Ray Jui <rjui at broadcom.com>
> >Cc: Jon Mason <jonmason at broadcom.com>
> >---
> >  drivers/pci/host/pcie-iproc.c | 94 ++++++++++++++++++++++++++++++++++---------
> >  1 file changed, 74 insertions(+), 20 deletions(-)
> >
> >diff --git a/drivers/pci/host/pcie-iproc.c b/drivers/pci/host/pcie-iproc.c
> >index 0f39bd2..e48b8e2 100644
> >--- a/drivers/pci/host/pcie-iproc.c
> >+++ b/drivers/pci/host/pcie-iproc.c
> >@@ -452,14 +452,13 @@ static inline void iproc_pcie_apb_err_disable(struct pci_bus *bus,
> >   * Note access to the configuration registers are protected at the higher layer
> >   * by 'pci_lock' in drivers/pci/access.c
> >   */
> >-static void __iomem *iproc_pcie_map_cfg_bus(struct pci_bus *bus,
> >+static void __iomem *iproc_pcie_map_cfg_bus(struct iproc_pcie *pcie,
> >+					    int busno,
> >  					    unsigned int devfn,
> >  					    int where)
> >  {
> >-	struct iproc_pcie *pcie = iproc_data(bus);
> >  	unsigned slot = PCI_SLOT(devfn);
> >  	unsigned fn = PCI_FUNC(devfn);
> >-	unsigned busno = bus->number;
> >  	u32 val;
> >  	u16 offset;
> >@@ -499,6 +498,58 @@ static void __iomem *iproc_pcie_map_cfg_bus(struct pci_bus *bus,
> >  		return (pcie->base + offset);
> >  }
> >+static void __iomem *iproc_pcie_bus_map_cfg_bus(struct pci_bus *bus,
> >+						unsigned int devfn,
> >+						int where)
> >+{
> >+	return iproc_pcie_map_cfg_bus(iproc_data(bus), bus->number, devfn,
> >+				      where);
> >+}
> >+
> >+static int iproc_pci_raw_config_read32(struct iproc_pcie *pcie,
> >+				       unsigned int devfn, int where,
> >+				       int size, u32 *val)
> >+{
> >+	void __iomem *addr;
> >+
> >+	addr = iproc_pcie_map_cfg_bus(pcie, 0, devfn, where & ~0x3);
> >+	if (!addr) {
> >+		*val = ~0;
> >+		return PCIBIOS_DEVICE_NOT_FOUND;
> >+	}
> >+
> >+	*val = readl(addr);
> >+
> >+	if (size <= 2)
> >+		*val = (*val >> (8 * (where & 3))) & ((1 << (size * 8)) - 1);
> >+
> >+	return PCIBIOS_SUCCESSFUL;
> >+}
> >+
> >+static int iproc_pci_raw_config_write32(struct iproc_pcie *pcie,
> >+					unsigned int devfn, int where,
> >+					int size, u32 val)
> >+{
> >+	void __iomem *addr;
> >+	u32 mask, tmp;
> >+
> >+	addr = iproc_pcie_map_cfg_bus(pcie, 0, devfn, where & ~0x3);
> >+	if (!addr)
> >+		return PCIBIOS_DEVICE_NOT_FOUND;
> >+
> >+	if (size == 4) {
> >+		writel(val, addr);
> >+		return PCIBIOS_SUCCESSFUL;
> >+	}
> >+
> >+	mask = ~(((1 << (size * 8)) - 1) << ((where & 0x3) * 8));
> >+	tmp = readl(addr) & mask;
> >+	tmp |= val << ((where & 0x3) * 8);
> >+	writel(tmp, addr);
> >+
> >+	return PCIBIOS_SUCCESSFUL;
> >+}
> >+
> >  static int iproc_pcie_config_read32(struct pci_bus *bus, unsigned int devfn,
> >  				    int where, int size, u32 *val)
> >  {
> >@@ -524,7 +575,7 @@ static int iproc_pcie_config_write32(struct pci_bus *bus, unsigned int devfn,
> >  }
> >  static struct pci_ops iproc_pcie_ops = {
> >-	.map_bus = iproc_pcie_map_cfg_bus,
> >+	.map_bus = iproc_pcie_bus_map_cfg_bus,
> >  	.read = iproc_pcie_config_read32,
> >  	.write = iproc_pcie_config_write32,
> >  };
> >@@ -556,12 +607,11 @@ static void iproc_pcie_reset(struct iproc_pcie *pcie)
> >  	msleep(100);
> >  }
> >-static int iproc_pcie_check_link(struct iproc_pcie *pcie, struct pci_bus *bus)
> >+static int iproc_pcie_check_link(struct iproc_pcie *pcie)
> >  {
> >  	struct device *dev = pcie->dev;
> >-	u8 hdr_type;
> >-	u32 link_ctrl, class, val;
> >-	u16 pos = PCI_EXP_CAP, link_status;
> >+	u32 hdr_type, link_ctrl, link_status, class, val;
> >+	u16 pos = PCI_EXP_CAP;
> >  	bool link_is_active = false;
> >  	/*
> >@@ -578,7 +628,7 @@ static int iproc_pcie_check_link(struct iproc_pcie *pcie, struct pci_bus *bus)
> >  	}
> >  	/* make sure we are not in EP mode */
> >-	pci_bus_read_config_byte(bus, 0, PCI_HEADER_TYPE, &hdr_type);
> >+	iproc_pci_raw_config_read32(pcie,  0, PCI_HEADER_TYPE, 1, &hdr_type);
> >  	if ((hdr_type & 0x7f) != PCI_HEADER_TYPE_BRIDGE) {
> >  		dev_err(dev, "in EP mode, hdr=%#02x\n", hdr_type);
> >  		return -EFAULT;
> >@@ -588,13 +638,16 @@ static int iproc_pcie_check_link(struct iproc_pcie *pcie, struct pci_bus *bus)
> >  #define PCI_BRIDGE_CTRL_REG_OFFSET 0x43c
> >  #define PCI_CLASS_BRIDGE_MASK      0xffff00
> >  #define PCI_CLASS_BRIDGE_SHIFT     8
> >-	pci_bus_read_config_dword(bus, 0, PCI_BRIDGE_CTRL_REG_OFFSET, &class);
> >+	iproc_pci_raw_config_read32(pcie, 0, PCI_BRIDGE_CTRL_REG_OFFSET,
> >+				    4, &class);
> >  	class &= ~PCI_CLASS_BRIDGE_MASK;
> >  	class |= (PCI_CLASS_BRIDGE_PCI << PCI_CLASS_BRIDGE_SHIFT);
> >-	pci_bus_write_config_dword(bus, 0, PCI_BRIDGE_CTRL_REG_OFFSET, class);
> >+	iproc_pci_raw_config_write32(pcie, 0, PCI_BRIDGE_CTRL_REG_OFFSET,
> >+				     4, class);
> >  	/* check link status to see if link is active */
> >-	pci_bus_read_config_word(bus, 0, pos + PCI_EXP_LNKSTA, &link_status);
> >+	iproc_pci_raw_config_read32(pcie, 0, pos + PCI_EXP_LNKSTA,
> >+				    2, &link_status);
> >  	if (link_status & PCI_EXP_LNKSTA_NLW)
> >  		link_is_active = true;
> >@@ -603,20 +656,21 @@ static int iproc_pcie_check_link(struct iproc_pcie *pcie, struct pci_bus *bus)
> >  #define PCI_TARGET_LINK_SPEED_MASK    0xf
> >  #define PCI_TARGET_LINK_SPEED_GEN2    0x2
> >  #define PCI_TARGET_LINK_SPEED_GEN1    0x1
> >-		pci_bus_read_config_dword(bus, 0,
> >-					  pos + PCI_EXP_LNKCTL2,
> >+		iproc_pci_raw_config_read32(pcie, 0,
> >+					  pos + PCI_EXP_LNKCTL2, 4,
> >  					  &link_ctrl);
> >  		if ((link_ctrl & PCI_TARGET_LINK_SPEED_MASK) ==
> >  		    PCI_TARGET_LINK_SPEED_GEN2) {
> >  			link_ctrl &= ~PCI_TARGET_LINK_SPEED_MASK;
> >  			link_ctrl |= PCI_TARGET_LINK_SPEED_GEN1;
> >-			pci_bus_write_config_dword(bus, 0,
> >-					   pos + PCI_EXP_LNKCTL2,
> >-					   link_ctrl);
> >+			iproc_pci_raw_config_write32(pcie, 0,
> >+						pos + PCI_EXP_LNKCTL2,
> >+						4, link_ctrl);
> >  			msleep(100);
> >-			pci_bus_read_config_word(bus, 0, pos + PCI_EXP_LNKSTA,
> >-						 &link_status);
> >+			iproc_pci_raw_config_read32(pcie, 0,
> >+						pos + PCI_EXP_LNKSTA,
> >+						2, &link_status);
> >  			if (link_status & PCI_EXP_LNKSTA_NLW)
> >  				link_is_active = true;
> >  		}
> >@@ -1260,7 +1314,7 @@ int iproc_pcie_setup(struct iproc_pcie *pcie, struct list_head *res)
> >  	}
> >  	pcie->root_bus = bus;
> >-	ret = iproc_pcie_check_link(pcie, bus);
> >+	ret = iproc_pcie_check_link(pcie);
> >  	if (ret) {
> >  		dev_err(dev, "no PCIe EP device detected\n");
> >  		goto err_rm_root_bus;
> 



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