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>

drivers/usb/host/ohci-hcd.c

@@ -86,6 +86,21 @@ static void ohci_stop (struct usb_hcd *hcd);
 static int ohci_restart (struct ohci_hcd *ohci);
 #endif
 
+#ifdef CONFIG_PCI
+static void quirk_amd_pll(int state);
+static void amd_iso_dev_put(void);
+#else
+static inline void quirk_amd_pll(int state)
+{
+	return;
+}
+static inline void amd_iso_dev_put(void)
+{
+	return;
+}
+#endif
+
+
 #include "ohci-hub.c"
 #include "ohci-dbg.c"
 #include "ohci-mem.c"
@@ -886,6 +901,8 @@ static void ohci_stop (struct usb_hcd *hcd)
 
 	if (quirk_zfmicro(ohci))
 		del_timer(&ohci->unlink_watchdog);
+	if (quirk_amdiso(ohci))
+		amd_iso_dev_put();
 
 	remove_debug_files (ohci);
 	ohci_mem_cleanup (ohci);

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.
 	 */

drivers/usb/host/ohci-q.c

@@ -49,6 +49,9 @@ __acquires(ohci->lock)
 	switch (usb_pipetype (urb->pipe)) {
 	case PIPE_ISOCHRONOUS:
 		ohci_to_hcd(ohci)->self.bandwidth_isoc_reqs--;
+		if (ohci_to_hcd(ohci)->self.bandwidth_isoc_reqs == 0
+				&& quirk_amdiso(ohci))
+			quirk_amd_pll(1);
 		break;
 	case PIPE_INTERRUPT:
 		ohci_to_hcd(ohci)->self.bandwidth_int_reqs--;
@@ -677,6 +680,9 @@ static void td_submit_urb (
 				data + urb->iso_frame_desc [cnt].offset,
 				urb->iso_frame_desc [cnt].length, urb, cnt);
 		}
+		if (ohci_to_hcd(ohci)->self.bandwidth_isoc_reqs == 0
+				&& quirk_amdiso(ohci))
+			quirk_amd_pll(0);
 		periodic = ohci_to_hcd(ohci)->self.bandwidth_isoc_reqs++ == 0
 			&& ohci_to_hcd(ohci)->self.bandwidth_int_reqs == 0;
 		break;

drivers/usb/host/ohci.h

@@ -401,6 +401,7 @@ struct ohci_hcd {
 #define	OHCI_QUIRK_NEC		0x40			/* lost interrupts */
 #define	OHCI_QUIRK_FRAME_NO	0x80			/* no big endian frame_no shift */
 #define	OHCI_QUIRK_HUB_POWER	0x100			/* distrust firmware power/oc setup */
+#define	OHCI_QUIRK_AMD_ISO	0x200			/* ISO transfers*/
 	// there are also chip quirks/bugs in init logic
 
 	struct work_struct	nec_work;	/* Worker for NEC quirk */
@@ -428,6 +429,10 @@ static inline int quirk_zfmicro(struct ohci_hcd *ohci)
 {
 	return ohci->flags & OHCI_QUIRK_ZFMICRO;
 }
+static inline int quirk_amdiso(struct ohci_hcd *ohci)
+{
+	return ohci->flags & OHCI_QUIRK_AMD_ISO;
+}
 #else
 static inline int quirk_nec(struct ohci_hcd *ohci)
 {
@@ -437,6 +442,10 @@ static inline int quirk_zfmicro(struct ohci_hcd *ohci)
 {
 	return 0;
 }
+static inline int quirk_amdiso(struct ohci_hcd *ohci)
+{
+	return 0;
+}
 #endif
 
 /* convert between an hcd pointer and the corresponding ohci_hcd */