fix ssb irq setup, allows ubsec_ssb devices on Asus WL500GP and Netgear WGT634U to work, no side effects noticed on other devices

SVN-Revision: 16416

target/linux/brcm47xx/patches-2.6.28/816-ssb_fix_irq_setup.patch

@@ -0,0 +1,185 @@
+the current ssb irq setup (in ssb_mipscore_init) have some problem :
+it configure some device on some irq without checking that the irq is not taken by an other device.
+
+For example in my case PCI host is on irq 0 and IPSEC on irq 3.
+The current code :
+- store in dev->irq that IPSEC irq is 3+2
+- do a set_irq 0->3 on PCI host
+
+But now IPSEC irq is not routed anymore to the mips code and dev->irq is wrong. This cause problem described in [1].
+
+This patch try to solve the problem by making set_irq configure the device we want to take the irq on the shared irq0.
+The previous example become :
+- store in dev->irq that IPSEC irq is 3+2
+- do a set_irq 0->3 on PCI host :
+  - irq 3 is already taken by IPSEC. do a set_irq 3->0 on IPSEC
+
+
+I also added some code to print the irq configuration before and after irq setup to allow easier debugging. And I add extra checking in ssb_mips_irq to report device without irq or device with not routed irq.
+
+
+[1] http://www.danm.de/files/src/bcm5365p/REPORTED_DEVICES
+
+Signed-off-by: Matthieu CASTET <[email protected]> 
+Index: linux-2.6/drivers/ssb/driver_mipscore.c
+===================================================================
+--- linux-2.6.orig/drivers/ssb/driver_mipscore.c	2009-05-25 19:47:26.000000000 +0200
++++ linux-2.6/drivers/ssb/driver_mipscore.c	2009-05-25 19:47:42.000000000 +0200
+@@ -49,29 +49,54 @@
+ 
+ static inline u32 ssb_irqflag(struct ssb_device *dev)
+ {
+-	return ssb_read32(dev, SSB_TPSFLAG) & SSB_TPSFLAG_BPFLAG;
++	u32 tpsflag = ssb_read32(dev, SSB_TPSFLAG);
++	if (tpsflag)
++		return ssb_read32(dev, SSB_TPSFLAG) & SSB_TPSFLAG_BPFLAG;
++	else
++		/* not irq supported */
++		return 0x3f;
++}
++
++static struct ssb_device *find_device(struct ssb_device *rdev, int irqflag)
++{
++	struct ssb_bus *bus = rdev->bus;
++	int i;
++	for (i = 0; i < bus->nr_devices; i++) {
++		struct ssb_device *dev;
++		dev = &(bus->devices[i]);
++		if (ssb_irqflag(dev) == irqflag)
++			return dev;
++	}
++	return NULL;
+ }
+ 
+ /* Get the MIPS IRQ assignment for a specified device.
+  * If unassigned, 0 is returned.
++ * If disabled, 5 is returned.
++ * If not supported, 6 is returned.
+  */
+ unsigned int ssb_mips_irq(struct ssb_device *dev)
+ {
+ 	struct ssb_bus *bus = dev->bus;
++	struct ssb_device *mdev = bus->mipscore.dev;
+ 	u32 irqflag;
+ 	u32 ipsflag;
+ 	u32 tmp;
+ 	unsigned int irq;
+ 
+ 	irqflag = ssb_irqflag(dev);
++	if (irqflag == 0x3f)
++		return 6;
+ 	ipsflag = ssb_read32(bus->mipscore.dev, SSB_IPSFLAG);
+ 	for (irq = 1; irq <= 4; irq++) {
+ 		tmp = ((ipsflag & ipsflag_irq_mask[irq]) >> ipsflag_irq_shift[irq]);
+ 		if (tmp == irqflag)
+ 			break;
+ 	}
+-	if (irq	== 5)
+-		irq = 0;
++	if (irq	== 5) {
++		if ((1 << irqflag) & ssb_read32(mdev, SSB_INTVEC))
++			irq = 0;
++	}
+ 
+ 	return irq;
+ }
+@@ -97,25 +122,56 @@
+ 	struct ssb_device *mdev = bus->mipscore.dev;
+ 	u32 irqflag = ssb_irqflag(dev);
+ 
++	BUG_ON(oldirq == 6);
++
+ 	dev->irq = irq + 2;
+ 
+-	ssb_dprintk(KERN_INFO PFX
+-		    "set_irq: core 0x%04x, irq %d => %d\n",
+-		    dev->id.coreid, oldirq, irq);
+ 	/* clear the old irq */
+ 	if (oldirq == 0)
+ 		ssb_write32(mdev, SSB_INTVEC, (~(1 << irqflag) & ssb_read32(mdev, SSB_INTVEC)));
+-	else
++	else if (oldirq != 5)
+ 		clear_irq(bus, oldirq);
+ 
+ 	/* assign the new one */
+ 	if (irq == 0) {
+ 		ssb_write32(mdev, SSB_INTVEC, ((1 << irqflag) | ssb_read32(mdev, SSB_INTVEC)));
+ 	} else {
++		u32 ipsflag = ssb_read32(mdev, SSB_IPSFLAG);
++		if ((ipsflag & ipsflag_irq_mask[irq]) != ipsflag_irq_mask[irq]) {
++			u32 oldipsflag = (ipsflag & ipsflag_irq_mask[irq]) >> ipsflag_irq_shift[irq];
++			struct ssb_device *olddev = find_device(dev, oldipsflag);
++			if (olddev)
++				set_irq(olddev, 0);
++		}
+ 		irqflag <<= ipsflag_irq_shift[irq];
+-		irqflag |= (ssb_read32(mdev, SSB_IPSFLAG) & ~ipsflag_irq_mask[irq]);
++		irqflag |= (ipsflag & ~ipsflag_irq_mask[irq]);
+ 		ssb_write32(mdev, SSB_IPSFLAG, irqflag);
+ 	}
++	ssb_dprintk(KERN_INFO PFX
++		    "set_irq: core 0x%04x, irq %d => %d\n",
++		    dev->id.coreid, oldirq+2, irq+2);
++}
++
++static void print_irq(struct ssb_device *dev, unsigned int irq)
++{
++	int i;
++	static const char *irq_name[] = {"2(S)", "3", "4", "5", "6", "D", "I"};
++	ssb_dprintk(KERN_INFO PFX
++		"core 0x%04x, irq :", dev->id.coreid);
++	for (i = 0; i <= 6; i++) {
++		ssb_dprintk(" %s%s", irq_name[i], i==irq?"*":" ");
++	}
++	ssb_dprintk("\n");
++}
++
++static void dump_irq(struct ssb_bus *bus)
++{
++	int i;
++	for (i = 0; i < bus->nr_devices; i++) {
++		struct ssb_device *dev;
++		dev = &(bus->devices[i]);
++		print_irq(dev, ssb_mips_irq(dev));
++	}
+ }
+ 
+ static void ssb_mips_serial_init(struct ssb_mipscore *mcore)
+@@ -195,18 +251,26 @@
+ 	else if (bus->chipco.dev)
+ 		ssb_chipco_timing_init(&bus->chipco, ns);
+ 
++	dump_irq(bus);
+ 	/* Assign IRQs to all cores on the bus, start with irq line 2, because serial usually takes 1 */
+ 	for (irq = 2, i = 0; i < bus->nr_devices; i++) {
++		int mips_irq;
+ 		dev = &(bus->devices[i]);
+-		dev->irq = ssb_mips_irq(dev) + 2;
++		mips_irq = ssb_mips_irq(dev);
++		if (mips_irq > 4)
++			dev->irq = 0;
++		else
++			dev->irq = mips_irq + 2;
++		if (dev->irq > 5)
++			continue;
+ 		switch (dev->id.coreid) {
+ 		case SSB_DEV_USB11_HOST:
+ 			/* shouldn't need a separate irq line for non-4710, most of them have a proper
+ 			 * external usb controller on the pci */
+ 			if ((bus->chip_id == 0x4710) && (irq <= 4)) {
+ 				set_irq(dev, irq++);
+-				break;
+ 			}
++			break;
+ 			/* fallthrough */
+ 		case SSB_DEV_PCI:
+ 		case SSB_DEV_ETHERNET:
+@@ -220,6 +284,8 @@
+ 			}
+ 		}
+ 	}
++	ssb_dprintk(KERN_INFO PFX "after irq reconfiguration\n");
++	dump_irq(bus);
+ 
+ 	ssb_mips_serial_init(mcore);
+ 	ssb_mips_flash_detect(mcore);