USB: quirk PLL power down mode

On some AMD 700 series southbridges, ISO OUT transfers (such as audio
playback through speakers) on the USB OHCI controller may be corrupted
when an A-Link express power saving feature is active.

PLL power down mode in conjunction with link power management feature
L1 being enabled is the bad combination ... this patch prevents them
from being enabled when ISO transfers are pending.

Signed-off-by: Crane Cai <crane.cai@amd.com>
Signed-off-by: Libin Yang <libin.yang@amd.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 132 insertions, 0 deletions

diff --git a/drivers/usb/host/ohci-pci.c b/drivers/usb/host/ohci-pci.c
index 4696cc9..083e8df 100644
--- a/drivers/usb/host/ohci-pci.c
+++ b/drivers/usb/host/ohci-pci.c
@@ -18,6 +18,28 @@
 #error "This file is PCI bus glue.  CONFIG_PCI must be defined."
 #endif
 
+#include <linux/pci.h>
+#include <linux/io.h>
+
+
+/* constants used to work around PM-related transfer
+ * glitches in some AMD 700 series southbridges
+ */
+#define AB_REG_BAR	0xf0
+#define AB_INDX(addr)	((addr) + 0x00)
+#define AB_DATA(addr)	((addr) + 0x04)
+#define AX_INDXC	0X30
+#define AX_DATAC	0x34
+
+#define NB_PCIE_INDX_ADDR	0xe0
+#define NB_PCIE_INDX_DATA	0xe4
+#define PCIE_P_CNTL		0x10040
+#define BIF_NB			0x10002
+
+static struct pci_dev *amd_smbus_dev;
+static struct pci_dev *amd_hb_dev;
+static int amd_ohci_iso_count;
+
 /*-------------------------------------------------------------------------*/
 
 static int broken_suspend(struct usb_hcd *hcd)
@@ -143,6 +165,103 @@ static int ohci_quirk_nec(struct usb_hcd *hcd)
 	return 0;
 }
 
+static int ohci_quirk_amd700(struct usb_hcd *hcd)
+{
+	struct ohci_hcd *ohci = hcd_to_ohci(hcd);
+	u8 rev = 0;
+
+	if (!amd_smbus_dev)
+		amd_smbus_dev = pci_get_device(PCI_VENDOR_ID_ATI,
+				PCI_DEVICE_ID_ATI_SBX00_SMBUS, NULL);
+	if (!amd_smbus_dev)
+		return 0;
+
+	pci_read_config_byte(amd_smbus_dev, PCI_REVISION_ID, &rev);
+	if ((rev > 0x3b) || (rev < 0x30)) {
+		pci_dev_put(amd_smbus_dev);
+		amd_smbus_dev = NULL;
+		return 0;
+	}
+
+	amd_ohci_iso_count++;
+
+	if (!amd_hb_dev)
+		amd_hb_dev = pci_get_device(PCI_VENDOR_ID_AMD, 0x9600, NULL);
+
+	ohci->flags |= OHCI_QUIRK_AMD_ISO;
+	ohci_dbg(ohci, "enabled AMD ISO transfers quirk\n");
+
+	return 0;
+}
+
+/*
+ * The hardware normally enables the A-link power management feature, which
+ * lets the system lower the power consumption in idle states.
+ *
+ * Assume the system is configured to have USB 1.1 ISO transfers going
+ * to or from a USB device.  Without this quirk, that stream may stutter
+ * or have breaks occasionally.  For transfers going to speakers, this
+ * makes a very audible mess...
+ *
+ * That audio playback corruption is due to the audio stream getting
+ * interrupted occasionally when the link goes in lower power state
+ * This USB quirk prevents the link going into that lower power state
+ * during audio playback or other ISO operations.
+ */
+static void quirk_amd_pll(int on)
+{
+	u32 addr;
+	u32 val;
+	u32 bit = (on > 0) ? 1 : 0;
+
+	pci_read_config_dword(amd_smbus_dev, AB_REG_BAR, &addr);
+
+	/* BIT names/meanings are NDA-protected, sorry ... */
+
+	outl(AX_INDXC, AB_INDX(addr));
+	outl(0x40, AB_DATA(addr));
+	outl(AX_DATAC, AB_INDX(addr));
+	val = inl(AB_DATA(addr));
+	val &= ~((1 << 3) | (1 << 4) | (1 << 9));
+	val |= (bit << 3) | ((!bit) << 4) | ((!bit) << 9);
+	outl(val, AB_DATA(addr));
+
+	if (amd_hb_dev) {
+		addr = PCIE_P_CNTL;
+		pci_write_config_dword(amd_hb_dev, NB_PCIE_INDX_ADDR, addr);
+
+		pci_read_config_dword(amd_hb_dev, NB_PCIE_INDX_DATA, &val);
+		val &= ~(1 | (1 << 3) | (1 << 4) | (1 << 9) | (1 << 12));
+		val |= bit | (bit << 3) | (bit << 12);
+		val |= ((!bit) << 4) | ((!bit) << 9);
+		pci_write_config_dword(amd_hb_dev, NB_PCIE_INDX_DATA, val);
+
+		addr = BIF_NB;
+		pci_write_config_dword(amd_hb_dev, NB_PCIE_INDX_ADDR, addr);
+
+		pci_read_config_dword(amd_hb_dev, NB_PCIE_INDX_DATA, &val);
+		val &= ~(1 << 8);
+		val |= bit << 8;
+		pci_write_config_dword(amd_hb_dev, NB_PCIE_INDX_DATA, val);
+	}
+}
+
+static void amd_iso_dev_put(void)
+{
+	amd_ohci_iso_count--;
+	if (amd_ohci_iso_count == 0) {
+		if (amd_smbus_dev) {
+			pci_dev_put(amd_smbus_dev);
+			amd_smbus_dev = NULL;
+		}
+		if (amd_hb_dev) {
+			pci_dev_put(amd_hb_dev);
+			amd_hb_dev = NULL;
+		}
+	}
+
+}
+
 /* List of quirks for OHCI */
 static const struct pci_device_id ohci_pci_quirks[] = {
 	{
@@ -181,6 +300,19 @@ static const struct pci_device_id ohci_pci_quirks[] = {
 		PCI_DEVICE(PCI_VENDOR_ID_ITE, 0x8152),
 		.driver_data = (unsigned long) broken_suspend,
 	},
+	{
+		PCI_DEVICE(PCI_VENDOR_ID_ATI, 0x4397),
+		.driver_data = (unsigned long)ohci_quirk_amd700,
+	},
+	{
+		PCI_DEVICE(PCI_VENDOR_ID_ATI, 0x4398),
+		.driver_data = (unsigned long)ohci_quirk_amd700,
+	},
+	{
+		PCI_DEVICE(PCI_VENDOR_ID_ATI, 0x4399),
+		.driver_data = (unsigned long)ohci_quirk_amd700,
+	},
+
 	/* FIXME for some of the early AMD 760 southbridges, OHCI
 	 * won't work at all.  blacklist them.
 	 */