Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1507790

[PATCH 02/12] PCI: iproc: Do not reset PAXC when initializing the driver

Show all headers | View raw

During initialization, the current iProc PCIe host driver resets PAXC
and the downstream internal endpoint device that PAXC connects to. If
the endpoint device is already loaded with firmware and has started
running from the bootloader stage, this downstream reset causes the
endpoint device to stop working

Signed-off-by: Ray Jui <raj.jui@broadcom.com>
Reviewed-by: Scott Branden <scott.branden@broadcom.com>
---
 drivers/pci/host/pcie-iproc.c | 15 ++++++---------
 1 file changed, 6 insertions(+), 9 deletions(-)

diff --git a/drivers/pci/host/pcie-iproc.c b/drivers/pci/host/pcie-iproc.c
index a9b9cd8..3f4884a 100644
--- a/drivers/pci/host/pcie-iproc.c
+++ b/drivers/pci/host/pcie-iproc.c
@@ -243,16 +243,13 @@ static void iproc_pcie_reset(struct iproc_pcie *pcie)
 {
 	u32 val;
 
-	if (pcie->ep_is_internal) {
-		val = iproc_pcie_read_reg(pcie, IPROC_PCIE_CLK_CTRL);
-		val &= ~PAXC_RESET_MASK;
-		iproc_pcie_write_reg(pcie, IPROC_PCIE_CLK_CTRL, val);
-		udelay(100);
-		val |= PAXC_RESET_MASK;
-		iproc_pcie_write_reg(pcie, IPROC_PCIE_CLK_CTRL, val);
-		udelay(100);
+	/*
+	 * PAXC and the internal emulated endpoint device downstream should not
+	 * be reset. If firmware has been loaded on the endpoint device at an
+	 * earlier boot stage, reset here causes issues
+	 */
+	if (pcie->ep_is_internal)
 		return;
-	}
 
 	/*
 	 * Select perst_b signal as reset source. Put the device into reset,
-- 
2.1.4

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH 00/12] Additional iProc PCIe host support/fixes Ray Jui <ray.jui@broadcom.com> - 2016-10-25 00:20 +0200
  [PATCH 02/12] PCI: iproc: Do not reset PAXC when initializing the driver Ray Jui <ray.jui@broadcom.com> - 2016-10-25 00:20 +0200
  [PATCH 05/12] PCI: iproc: Update iProc PCIe DT binding Ray Jui <ray.jui@broadcom.com> - 2016-10-25 00:20 +0200
  [PATCH 07/12] PCI: iproc: Update iProc PCIe DT binding Ray Jui <ray.jui@broadcom.com> - 2016-10-25 00:30 +0200
    Re: [PATCH 07/12] PCI: iproc: Update iProc PCIe DT binding Scott Branden <scott.branden@broadcom.com> - 2016-10-25 00:30 +0200
      Re: [PATCH 07/12] PCI: iproc: Update iProc PCIe DT binding Ray Jui <ray.jui@broadcom.com> - 2016-10-25 00:30 +0200
  Re: [PATCH 00/12] Additional iProc PCIe host support/fixes Scott Branden <scott.branden@broadcom.com> - 2016-10-25 00:40 +0200
    Re: [PATCH 00/12] Additional iProc PCIe host support/fixes Ray Jui <ray.jui@broadcom.com> - 2016-10-25 00:40 +0200
  Re: [PATCH 00/12] Additional iProc PCIe host support/fixes Bjorn Helgaas <helgaas@kernel.org> - 2016-10-25 01:00 +0200
    Re: [PATCH 00/12] Additional iProc PCIe host support/fixes Ray Jui <ray.jui@broadcom.com> - 2016-10-25 01:00 +0200

csiph-web