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[1/1,SRU,Xenial] xhci: Bad Ethernet performance plugged in ASM1042A host

Message ID 20170719074436.25590-3-kai.heng.feng@canonical.com
State New
Headers show

Commit Message

Kai-Heng Feng July 19, 2017, 7:44 a.m. UTC
From: Jiahau Chang <jiahau@gmail.com>

BugLink: https://bugs.launchpad.net/bugs/1667750

When USB Ethernet is plugged in ASMEDIA ASM1042A xHCI host, bad
performance was manifesting in Web browser use (like download
large file such as ISO image). It is known limitation of
ASM1042A that is not compatible with driver scheduling,
As a workaround we can modify flow control handling of ASM1042A.
The register we modify is changes the behavior

[use quirk bit 28 instead, usleep_range 40-60us -Mathias]
Cc: <stable@vger.kernel.org>
Signed-off-by: Jiahau Chang <Lars_chang@asmedia.com.tw>
Signed-off-by: Ian Pilcher <arequipeno@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
(backported from commit 84f0e8acbfd8327131f2c6fe592013d43258b538 git://git.kernel.org/pub/scm/linux/kernel/git/mnyman/xhci.git for-usb-linus)
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
---
 drivers/usb/host/pci-quirks.c | 54 +++++++++++++++++++++++++++++++++++++++++++
 drivers/usb/host/pci-quirks.h |  1 +
 drivers/usb/host/xhci-pci.c   |  6 +++++
 drivers/usb/host/xhci.c       |  6 +++++
 drivers/usb/host/xhci.h       |  1 +
 5 files changed, 68 insertions(+)
diff mbox

Patch

diff --git a/drivers/usb/host/pci-quirks.c b/drivers/usb/host/pci-quirks.c
index f9400564cb72..749d8df5e351 100644
--- a/drivers/usb/host/pci-quirks.c
+++ b/drivers/usb/host/pci-quirks.c
@@ -78,6 +78,16 @@ 
 #define USB_INTEL_USB3_PSSEN   0xD8
 #define USB_INTEL_USB3PRM      0xDC
 
+/* ASMEDIA quirk use */
+#define ASMT_DATA_WRITE0_REG	0xF8
+#define ASMT_DATA_WRITE1_REG	0xFC
+#define ASMT_CONTROL_REG	0xE0
+#define ASMT_CONTROL_WRITE_BIT	0x02
+#define ASMT_WRITEREG_CMD	0x10423
+#define ASMT_FLOWCTL_ADDR	0xFA30
+#define ASMT_FLOWCTL_DATA	0xBA
+#define ASMT_PSEUDO_DATA	0
+
 /*
  * amd_chipset_gen values represent AMD different chipset generations
  */
@@ -413,6 +423,50 @@  void usb_amd_quirk_pll_disable(void)
 }
 EXPORT_SYMBOL_GPL(usb_amd_quirk_pll_disable);
 
+static int usb_asmedia_wait_write(struct pci_dev *pdev)
+{
+	unsigned long retry_count;
+	unsigned char value;
+
+	for (retry_count = 1000; retry_count > 0; --retry_count) {
+
+		pci_read_config_byte(pdev, ASMT_CONTROL_REG, &value);
+
+		if (value == 0xff) {
+			dev_err(&pdev->dev, "%s: check_ready ERROR", __func__);
+			return -EIO;
+		}
+
+		if ((value & ASMT_CONTROL_WRITE_BIT) == 0)
+			return 0;
+
+		usleep_range(40, 60);
+	}
+
+	dev_warn(&pdev->dev, "%s: check_write_ready timeout", __func__);
+	return -ETIMEDOUT;
+}
+
+void usb_asmedia_modifyflowcontrol(struct pci_dev *pdev)
+{
+	if (usb_asmedia_wait_write(pdev) != 0)
+		return;
+
+	/* send command and address to device */
+	pci_write_config_dword(pdev, ASMT_DATA_WRITE0_REG, ASMT_WRITEREG_CMD);
+	pci_write_config_dword(pdev, ASMT_DATA_WRITE1_REG, ASMT_FLOWCTL_ADDR);
+	pci_write_config_byte(pdev, ASMT_CONTROL_REG, ASMT_CONTROL_WRITE_BIT);
+
+	if (usb_asmedia_wait_write(pdev) != 0)
+		return;
+
+	/* send data to device */
+	pci_write_config_dword(pdev, ASMT_DATA_WRITE0_REG, ASMT_FLOWCTL_DATA);
+	pci_write_config_dword(pdev, ASMT_DATA_WRITE1_REG, ASMT_PSEUDO_DATA);
+	pci_write_config_byte(pdev, ASMT_CONTROL_REG, ASMT_CONTROL_WRITE_BIT);
+}
+EXPORT_SYMBOL_GPL(usb_asmedia_modifyflowcontrol);
+
 void usb_amd_quirk_pll_enable(void)
 {
 	usb_amd_quirk_pll(0);
diff --git a/drivers/usb/host/pci-quirks.h b/drivers/usb/host/pci-quirks.h
index c622ddf21c94..c78a0dc42d10 100644
--- a/drivers/usb/host/pci-quirks.h
+++ b/drivers/usb/host/pci-quirks.h
@@ -11,6 +11,7 @@  bool usb_amd_prefetch_quirk(void);
 void usb_amd_dev_put(void);
 void usb_amd_quirk_pll_disable(void);
 void usb_amd_quirk_pll_enable(void);
+void usb_asmedia_modifyflowcontrol(struct pci_dev *pdev);
 void usb_enable_intel_xhci_ports(struct pci_dev *xhci_pdev);
 void usb_disable_xhci_ports(struct pci_dev *xhci_pdev);
 void sb800_prefetch(struct device *dev, int on);
diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index 56b756d34819..fd4b6127d4dd 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -59,6 +59,8 @@ 
 #define PCI_DEVICE_ID_AMD_PROMONTORYA_2			0x43bb
 #define PCI_DEVICE_ID_AMD_PROMONTORYA_1			0x43bc
 
+#define PCI_DEVICE_ID_ASMEDIA_1042A_XHCI		0x1142
+
 static const char hcd_name[] = "xhci_hcd";
 
 static struct hc_driver __read_mostly xhci_pci_hc_driver;
@@ -215,6 +217,10 @@  static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
 			pdev->device == 0x1142)
 		xhci->quirks |= XHCI_TRUST_TX_LENGTH;
 
+	if (pdev->vendor == PCI_VENDOR_ID_ASMEDIA &&
+		pdev->device == PCI_DEVICE_ID_ASMEDIA_1042A_XHCI)
+		xhci->quirks |= XHCI_ASMEDIA_MODIFY_FLOWCONTROL;
+
 	if (xhci->quirks & XHCI_RESET_ON_RESUME)
 		xhci_dbg_trace(xhci, trace_xhci_dbg_quirks,
 				"QUIRK: Resetting on resume");
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index cb3d428036c0..60d3d9d600d2 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -191,6 +191,9 @@  int xhci_reset(struct xhci_hcd *xhci)
 	if (ret)
 		return ret;
 
+	if (xhci->quirks & XHCI_ASMEDIA_MODIFY_FLOWCONTROL)
+		usb_asmedia_modifyflowcontrol(to_pci_dev(xhci_to_hcd(xhci)->self.controller));
+
 	xhci_dbg_trace(xhci, trace_xhci_dbg_init,
 			 "Wait for controller to be ready for doorbell rings");
 	/*
@@ -1121,6 +1124,9 @@  int xhci_resume(struct xhci_hcd *xhci, bool hibernated)
 	if ((xhci->quirks & XHCI_COMP_MODE_QUIRK) && !comp_timer_running)
 		compliance_mode_recovery_timer_init(xhci);
 
+	if (xhci->quirks & XHCI_ASMEDIA_MODIFY_FLOWCONTROL)
+		usb_asmedia_modifyflowcontrol(to_pci_dev(hcd->self.controller));
+
 	/* Re-enable port polling. */
 	xhci_dbg(xhci, "%s: starting port polling.\n", __func__);
 	set_bit(HCD_FLAG_POLL_RH, &xhci->shared_hcd->flags);
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index d723fef01001..0607dd4aa8d2 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1645,6 +1645,7 @@  struct xhci_hcd {
 #define XHCI_PME_STUCK_QUIRK	(1 << 20)
 #define XHCI_MISSING_CAS	(1 << 24)
 #define XHCI_U2_DISABLE_WAKE    (1 << 27)
+#define XHCI_ASMEDIA_MODIFY_FLOWCONTROL	(1 << 28)
 
 	unsigned int		num_active_eps;
 	unsigned int		limit_active_eps;