[PATCH 1/1] [SRU Xenial] xhci: Bad Ethernet performance plugged in ASM1042A host
Kai-Heng Feng
kai.heng.feng at canonical.com
Wed Jul 19 07:44:35 UTC 2017
From: Jiahau Chang <jiahau at 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 at vger.kernel.org>
Signed-off-by: Jiahau Chang <Lars_chang at asmedia.com.tw>
Signed-off-by: Ian Pilcher <arequipeno at gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman at 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 at 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 --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;
--
2.13.3
More information about the kernel-team
mailing list