diff options
| author | Jiahau Chang <jiahau@gmail.com> | 2017-07-20 14:48:27 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-07-20 14:40:35 +0200 |
| commit | 9da5a1092b13468839b1a864b126cacfb72ad016 (patch) | |
| tree | 150639fa1c21c53e0d6988bd3b2f5d1a10e2e904 /drivers/usb/host/pci-quirks.c | |
| parent | 4b895868bb2da60a386a17cde3bf9ecbc70c79f4 (diff) | |
xhci: Bad Ethernet performance plugged in ASM1042A host
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, usleep_range 40-60us, empty non-pci function -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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/host/pci-quirks.c')
| -rw-r--r-- | drivers/usb/host/pci-quirks.c | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/drivers/usb/host/pci-quirks.c b/drivers/usb/host/pci-quirks.c index a9a1e4c40480..c8989c62a262 100644 --- a/drivers/usb/host/pci-quirks.c +++ b/drivers/usb/host/pci-quirks.c @@ -77,6 +77,16 @@ #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 */ @@ -412,6 +422,50 @@ 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); |