patch-2.4.20 linux-2.4.20/drivers/gsc/gsc.c

• Lines: 205
• Date: Thu Nov 28 15:53:12 2002
• Orig file: linux-2.4.19/drivers/gsc/gsc.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -urN linux-2.4.19/drivers/gsc/gsc.c linux-2.4.20/drivers/gsc/gsc.c
@@ -0,0 +1,204 @@
+/*
+ * Interrupt management for most GSC and related devices.
+ *
+ * (c) Copyright 1999 Alex deVries for The Puffin Group
+ * (c) Copyright 1999 Grant Grundler for Hewlett-Packard
+ * (c) Copyright 1999 Matthew Wilcox
+ * (c) Copyright 2000 Helge Deller
+ * (c) Copyright 2001 Matthew Wilcox for Hewlett-Packard
+ *
+ *	This program is free software; you can redistribute it and/or modify
+ *	it under the terms of the GNU General Public License as published by
+ *      the Free Software Foundation; either version 2 of the License, or
+ *      (at your option) any later version.
+ */
+
+#include <linux/bitops.h>
+#include <linux/config.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#include <asm/gsc.h>
+#include <asm/hardware.h>
+#include <asm/io.h>
+#include <asm/irq.h>
+
+#include "busdevice.h"
+
+#undef DEBUG
+
+#ifdef DEBUG
+#define DEBPRINTK printk
+#else
+#define DEBPRINTK(x,...)
+#endif
+
+int gsc_alloc_irq(struct gsc_irq *i)
+{
+	int irq = txn_alloc_irq();
+	if (irq < 0) {
+		printk("cannot get irq\n");
+		return irq;
+	}
+
+	i->txn_addr = txn_alloc_addr(irq);
+	i->txn_data = txn_alloc_data(irq, GSC_EIM_WIDTH);
+	i->irq = irq;
+
+	return irq;
+}
+
+
+int gsc_claim_irq(struct gsc_irq *i, int irq)
+{
+	int c = irq;
+
+	irq += IRQ_FROM_REGION(CPU_IRQ_REGION); /* virtualize the IRQ first */
+
+	irq = txn_claim_irq(irq);
+	if (irq < 0) {
+		printk("cannot claim irq %d\n", c);
+		return irq;
+	}
+
+	i->txn_addr = txn_alloc_addr(irq);
+	i->txn_data = txn_alloc_data(irq, GSC_EIM_WIDTH);
+	i->irq = irq;
+
+	return irq;
+}
+
+
+/* IRQ bits must be numbered from Most Significant Bit */
+#define GSC_FIX_IRQ(x)	(31-(x))
+#define GSC_MASK_IRQ(x)	(1<<(GSC_FIX_IRQ(x)))
+
+/* Common interrupt demultiplexer used by Asp, Lasi & Wax.  */
+void busdev_barked(int busdev_irq, void *dev, struct pt_regs *regs)
+{
+	unsigned long irq;
+	struct busdevice *busdev = (struct busdevice *) dev;
+
+	/* 
+	    Don't need to protect OFFSET_IRR with spinlock since this is
+	    the only place it's touched.
+	    Protect busdev_region by disabling this region's interrupts,
+	    modifying the region, and then re-enabling the region.
+	*/
+
+	irq = gsc_readl(busdev->hpa+OFFSET_IRR);
+	if (irq == 0) {
+		printk(KERN_ERR "%s: barking without apparent reason.\n", busdev->name);
+	} else {
+		DEBPRINTK ("%s (0x%x) barked, mask=0x%x, irq=%d\n", 
+		    busdev->name, busdev->busdev_region->data.irqbase, 
+		    irq, GSC_FIX_IRQ(ffs(irq))+1 );
+
+		do_irq_mask(irq, busdev->busdev_region, regs);
+	}
+}
+
+static void
+busdev_disable_irq(void *irq_dev, int irq)
+{
+	/* Disable the IRQ line by clearing the bit in the IMR */
+	u32 imr = gsc_readl(BUSDEV_DEV(irq_dev)->hpa+OFFSET_IMR);
+	imr &= ~(GSC_MASK_IRQ(irq));
+
+	DEBPRINTK( KERN_WARNING "%s(%p, %d) %s: IMR 0x%x\n", 
+		    __FUNCTION__, irq_dev, irq, BUSDEV_DEV(irq_dev)->name, imr);
+
+	gsc_writel(imr, BUSDEV_DEV(irq_dev)->hpa+OFFSET_IMR);
+}
+
+
+static void
+busdev_enable_irq(void *irq_dev, int irq)
+{
+	/* Enable the IRQ line by setting the bit in the IMR */
+	unsigned long addr = BUSDEV_DEV(irq_dev)->hpa + OFFSET_IMR;
+	u32 imr = gsc_readl(addr);
+	imr |= GSC_MASK_IRQ(irq);
+
+	DEBPRINTK (KERN_WARNING "%s(%p, %d) %s: IMR 0x%x\n", 
+		    __FUNCTION__, irq_dev, irq, BUSDEV_DEV(irq_dev)->name, imr);
+
+	gsc_writel(imr, addr);
+//	gsc_writel(~0L, addr);
+
+/* FIXME: read IPR to make sure the IRQ isn't already pending.
+**   If so, we need to read IRR and manually call do_irq_mask().
+**   This code should be shared with busdev_unmask_irq().
+*/
+}
+
+static void
+busdev_mask_irq(void *irq_dev, int irq)
+{
+/* FIXME: Clear the IMR bit in busdev for that IRQ */
+}
+
+static void
+busdev_unmask_irq(void *irq_dev, int irq)
+{
+/* FIXME: Read IPR. Set the IMR bit in busdev for that IRQ.
+   call do_irq_mask() if IPR is non-zero
+*/
+}
+
+struct irq_region_ops busdev_irq_ops = {
+	disable_irq:	busdev_disable_irq,
+	enable_irq:	busdev_enable_irq,
+	mask_irq:	busdev_mask_irq,
+	unmask_irq:	busdev_unmask_irq
+};
+
+
+int gsc_common_irqsetup(struct parisc_device *parent, struct busdevice *busdev)
+{
+	struct resource *res;
+
+	busdev->gsc = parent;
+
+	/* the IRQs we simulate */
+	busdev->busdev_region = alloc_irq_region(32, &busdev_irq_ops,
+						 busdev->name, busdev);
+	if (!busdev->busdev_region)
+		return -ENOMEM;
+
+	/* allocate resource region */
+	res = request_mem_region(busdev->hpa, 0x100000, busdev->name);
+	if (res) {
+		res->flags = IORESOURCE_MEM; 	/* do not mark it busy ! */
+	}
+
+#if 0
+	printk(KERN_WARNING "%s IRQ %d EIM 0x%x", busdev->name,
+			busdev->parent_irq, busdev->eim);
+	if (gsc_readl(busdev->hpa + OFFSET_IMR))
+		printk("  IMR is non-zero! (0x%x)",
+				gsc_readl(busdev->hpa + OFFSET_IMR));
+	printk("\n");
+#endif
+
+	return 0;
+}
+
+extern struct parisc_driver lasi_driver;
+extern struct parisc_driver asp_driver;
+extern struct parisc_driver wax_driver;
+
+void __init gsc_init(void)
+{
+#ifdef CONFIG_GSC_LASI
+	register_parisc_driver(&lasi_driver);
+	register_parisc_driver(&asp_driver);
+#endif
+#ifdef CONFIG_GSC_WAX
+	register_parisc_driver(&wax_driver);
+#endif
+}