1 files changed, 314 insertions, 12 deletions

diff --git a/arch/mips/sni/rm200.c b/arch/mips/sni/rm200.c
index 67b061eef6cd..5310aa75afa4 100644
--- a/arch/mips/sni/rm200.c
+++ b/arch/mips/sni/rm200.c
@@ -5,30 +5,36 @@
  * License.  See the file "COPYING" in the main directory of this archive
  * for more details.
  *
- * Copyright (C) 2006 Thomas Bogendoerfer (tsbogend@alpha.franken.de)
+ * Copyright (C) 2006,2007 Thomas Bogendoerfer (tsbogend@alpha.franken.de)
+ *
+ * i8259 parts ripped out of arch/mips/kernel/i8259.c
  */
 
+#include <linux/delay.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/platform_device.h>
 #include <linux/serial_8250.h>
+#include <linux/io.h>
 
 #include <asm/sni.h>
 #include <asm/time.h>
 #include <asm/irq_cpu.h>
 
-#define PORT(_base,_irq)                                \
+#define RM200_I8259A_IRQ_BASE 32
+
+#define MEMPORT(_base,_irq)                             \
         {                                               \
-                .iobase         = _base,                \
+                .mapbase        = _base,                \
                 .irq            = _irq,                 \
                 .uartclk        = 1843200,              \
-                .iotype         = UPIO_PORT,            \
-                .flags          = UPF_BOOT_AUTOCONF,    \
+                .iotype         = UPIO_MEM,             \
+                .flags          = UPF_BOOT_AUTOCONF|UPF_IOREMAP, \
         }
 
 static struct plat_serial8250_port rm200_data[] = {
-        PORT(0x3f8, 4),
-        PORT(0x2f8, 3),
+        MEMPORT(0x160003f8, RM200_I8259A_IRQ_BASE + 4),
+        MEMPORT(0x160002f8, RM200_I8259A_IRQ_BASE + 3),
         { },
 };
 
@@ -112,15 +118,311 @@ static int __init snirm_setup_devinit(void)
                 platform_device_register(&rm200_ds1216_device);
                 platform_device_register(&snirm_82596_rm200_pdev);
                 platform_device_register(&snirm_53c710_rm200_pdev);
+                sni_eisa_root_init();
         }
         return 0;
 }
 
 device_initcall(snirm_setup_devinit);
 
+/*
+ * RM200 has an ISA and an EISA bus. The iSA bus is only used
+ * for onboard devices and also has twi i8259 PICs. Since these
+ * PICs are no accessible via inb/outb the following code uses
+ * readb/writeb to access them
+ */
+
+DEFINE_SPINLOCK(sni_rm200_i8259A_lock);
+#define PIC_CMD    0x00
+#define PIC_IMR    0x01
+#define PIC_ISR    PIC_CMD
+#define PIC_POLL   PIC_ISR
+#define PIC_OCW3   PIC_ISR
+
+/* i8259A PIC related value */
+#define PIC_CASCADE_IR          2
+#define MASTER_ICW4_DEFAULT     0x01
+#define SLAVE_ICW4_DEFAULT      0x01
+
+/*
+ * This contains the irq mask for both 8259A irq controllers,
+ */
+static unsigned int rm200_cached_irq_mask = 0xffff;
+static __iomem u8 *rm200_pic_master;
+static __iomem u8 *rm200_pic_slave;
+
+#define cached_master_mask      (rm200_cached_irq_mask)
+#define cached_slave_mask       (rm200_cached_irq_mask >> 8)
+
+static void sni_rm200_disable_8259A_irq(unsigned int irq)
+{
+        unsigned int mask;
+        unsigned long flags;
+
+        irq -= RM200_I8259A_IRQ_BASE;
+        mask = 1 << irq;
+        spin_lock_irqsave(&sni_rm200_i8259A_lock, flags);
+        rm200_cached_irq_mask |= mask;
+        if (irq & 8)
+                writeb(cached_slave_mask, rm200_pic_slave + PIC_IMR);
+        else
+                writeb(cached_master_mask, rm200_pic_master + PIC_IMR);
+        spin_unlock_irqrestore(&sni_rm200_i8259A_lock, flags);
+}
+
+static void sni_rm200_enable_8259A_irq(unsigned int irq)
+{
+        unsigned int mask;
+        unsigned long flags;
+
+        irq -= RM200_I8259A_IRQ_BASE;
+        mask = ~(1 << irq);
+        spin_lock_irqsave(&sni_rm200_i8259A_lock, flags);
+        rm200_cached_irq_mask &= mask;
+        if (irq & 8)
+                writeb(cached_slave_mask, rm200_pic_slave + PIC_IMR);
+        else
+                writeb(cached_master_mask, rm200_pic_master + PIC_IMR);
+        spin_unlock_irqrestore(&sni_rm200_i8259A_lock, flags);
+}
+
+static inline int sni_rm200_i8259A_irq_real(unsigned int irq)
+{
+        int value;
+        int irqmask = 1 << irq;
+
+        if (irq < 8) {
+                writeb(0x0B, rm200_pic_master + PIC_CMD);
+                value = readb(rm200_pic_master + PIC_CMD) & irqmask;
+                writeb(0x0A, rm200_pic_master + PIC_CMD);
+                return value;
+        }
+        writeb(0x0B, rm200_pic_slave + PIC_CMD); /* ISR register */
+        value = readb(rm200_pic_slave + PIC_CMD) & (irqmask >> 8);
+        writeb(0x0A, rm200_pic_slave + PIC_CMD);
+        return value;
+}
+
+/*
+ * Careful! The 8259A is a fragile beast, it pretty
+ * much _has_ to be done exactly like this (mask it
+ * first, _then_ send the EOI, and the order of EOI
+ * to the two 8259s is important!
+ */
+void sni_rm200_mask_and_ack_8259A(unsigned int irq)
+{
+        unsigned int irqmask;
+        unsigned long flags;
+
+        irq -= RM200_I8259A_IRQ_BASE;
+        irqmask = 1 << irq;
+        spin_lock_irqsave(&sni_rm200_i8259A_lock, flags);
+        /*
+         * Lightweight spurious IRQ detection. We do not want
+         * to overdo spurious IRQ handling - it's usually a sign
+         * of hardware problems, so we only do the checks we can
+         * do without slowing down good hardware unnecessarily.
+         *
+         * Note that IRQ7 and IRQ15 (the two spurious IRQs
+         * usually resulting from the 8259A-1|2 PICs) occur
+         * even if the IRQ is masked in the 8259A. Thus we
+         * can check spurious 8259A IRQs without doing the
+         * quite slow i8259A_irq_real() call for every IRQ.
+         * This does not cover 100% of spurious interrupts,
+         * but should be enough to warn the user that there
+         * is something bad going on ...
+         */
+        if (rm200_cached_irq_mask & irqmask)
+                goto spurious_8259A_irq;
+        rm200_cached_irq_mask |= irqmask;
+
+handle_real_irq:
+        if (irq & 8) {
+                readb(rm200_pic_slave + PIC_IMR);
+                writeb(cached_slave_mask, rm200_pic_slave + PIC_IMR);
+                writeb(0x60+(irq & 7), rm200_pic_slave + PIC_CMD);
+                writeb(0x60+PIC_CASCADE_IR, rm200_pic_master + PIC_CMD);
+        } else {
+                readb(rm200_pic_master + PIC_IMR);
+                writeb(cached_master_mask, rm200_pic_master + PIC_IMR);
+                writeb(0x60+irq, rm200_pic_master + PIC_CMD);
+        }
+        spin_unlock_irqrestore(&sni_rm200_i8259A_lock, flags);
+        return;
+
+spurious_8259A_irq:
+        /*
+         * this is the slow path - should happen rarely.
+         */
+        if (sni_rm200_i8259A_irq_real(irq))
+                /*
+                 * oops, the IRQ _is_ in service according to the
+                 * 8259A - not spurious, go handle it.
+                 */
+                goto handle_real_irq;
+
+        {
+                static int spurious_irq_mask;
+                /*
+                 * At this point we can be sure the IRQ is spurious,
+                 * lets ACK and report it. [once per IRQ]
+                 */
+                if (!(spurious_irq_mask & irqmask)) {
+                        printk(KERN_DEBUG
+                               "spurious RM200 8259A interrupt: IRQ%d.\n", irq);
+                        spurious_irq_mask |= irqmask;
+                }
+                atomic_inc(&irq_err_count);
+                /*
+                 * Theoretically we do not have to handle this IRQ,
+                 * but in Linux this does not cause problems and is
+                 * simpler for us.
+                 */
+                goto handle_real_irq;
+        }
+}
+
+static struct irq_chip sni_rm200_i8259A_chip = {
+        .name           = "RM200-XT-PIC",
+        .mask           = sni_rm200_disable_8259A_irq,
+        .unmask         = sni_rm200_enable_8259A_irq,
+        .mask_ack       = sni_rm200_mask_and_ack_8259A,
+};
+
+/*
+ * Do the traditional i8259 interrupt polling thing.  This is for the few
+ * cases where no better interrupt acknowledge method is available and we
+ * absolutely must touch the i8259.
+ */
+static inline int sni_rm200_i8259_irq(void)
+{
+        int irq;
+
+        spin_lock(&sni_rm200_i8259A_lock);
+
+        /* Perform an interrupt acknowledge cycle on controller 1. */
+        writeb(0x0C, rm200_pic_master + PIC_CMD);       /* prepare for poll */
+        irq = readb(rm200_pic_master + PIC_CMD) & 7;
+        if (irq == PIC_CASCADE_IR) {
+                /*
+                 * Interrupt is cascaded so perform interrupt
+                 * acknowledge on controller 2.
+                 */
+                writeb(0x0C, rm200_pic_slave + PIC_CMD); /* prepare for poll */
+                irq = (readb(rm200_pic_slave + PIC_CMD) & 7) + 8;
+        }
+
+        if (unlikely(irq == 7)) {
+                /*
+                 * This may be a spurious interrupt.
+                 *
+                 * Read the interrupt status register (ISR). If the most
+                 * significant bit is not set then there is no valid
+                 * interrupt.
+                 */
+                writeb(0x0B, rm200_pic_master + PIC_ISR); /* ISR register */
+                if (~readb(rm200_pic_master + PIC_ISR) & 0x80)
+                        irq = -1;
+        }
+
+        spin_unlock(&sni_rm200_i8259A_lock);
+
+        return likely(irq >= 0) ? irq + RM200_I8259A_IRQ_BASE : irq;
+}
+
+void sni_rm200_init_8259A(void)
+{
+        unsigned long flags;
+
+        spin_lock_irqsave(&sni_rm200_i8259A_lock, flags);
+
+        writeb(0xff, rm200_pic_master + PIC_IMR);
+        writeb(0xff, rm200_pic_slave + PIC_IMR);
+
+        writeb(0x11, rm200_pic_master + PIC_CMD);
+        writeb(0, rm200_pic_master + PIC_IMR);
+        writeb(1U << PIC_CASCADE_IR, rm200_pic_master + PIC_IMR);
+        writeb(MASTER_ICW4_DEFAULT, rm200_pic_master + PIC_IMR);
+        writeb(0x11, rm200_pic_slave + PIC_CMD);
+        writeb(8, rm200_pic_slave + PIC_IMR);
+        writeb(PIC_CASCADE_IR, rm200_pic_slave + PIC_IMR);
+        writeb(SLAVE_ICW4_DEFAULT, rm200_pic_slave + PIC_IMR);
+        udelay(100);            /* wait for 8259A to initialize */
+
+        writeb(cached_master_mask, rm200_pic_master + PIC_IMR);
+        writeb(cached_slave_mask, rm200_pic_slave + PIC_IMR);
+
+        spin_unlock_irqrestore(&sni_rm200_i8259A_lock, flags);
+}
+
+/*
+ * IRQ2 is cascade interrupt to second interrupt controller
+ */
+static struct irqaction sni_rm200_irq2 = {
+        no_action, 0, CPU_MASK_NONE, "cascade", NULL, NULL
+};
+
+static struct resource sni_rm200_pic1_resource = {
+        .name = "onboard ISA pic1",
+        .start = 0x16000020,
+        .end = 0x16000023,
+        .flags = IORESOURCE_BUSY
+};
+
+static struct resource sni_rm200_pic2_resource = {
+        .name = "onboard ISA pic2",
+        .start = 0x160000a0,
+        .end = 0x160000a3,
+        .flags = IORESOURCE_BUSY
+};
+
+/* ISA irq handler */
+static irqreturn_t sni_rm200_i8259A_irq_handler(int dummy, void *p)
+{
+        int irq;
+
+        irq = sni_rm200_i8259_irq();
+        if (unlikely(irq < 0))
+                return IRQ_NONE;
+
+        do_IRQ(irq);
+        return IRQ_HANDLED;
+}
+
+struct irqaction sni_rm200_i8259A_irq = {
+        .handler = sni_rm200_i8259A_irq_handler,
+        .name = "onboard ISA",
+        .flags = IRQF_SHARED
+};
+
+void __init sni_rm200_i8259_irqs(void)
+{
+        int i;
+
+        rm200_pic_master = ioremap_nocache(0x16000020, 4);
+        if (!rm200_pic_master)
+                return;
+        rm200_pic_slave = ioremap_nocache(0x160000a0, 4);
+        if (!rm200_pic_master) {
+                iounmap(rm200_pic_master);
+                return;
+        }
+
+        insert_resource(&iomem_resource, &sni_rm200_pic1_resource);
+        insert_resource(&iomem_resource, &sni_rm200_pic2_resource);
+
+        sni_rm200_init_8259A();
+
+        for (i = RM200_I8259A_IRQ_BASE; i < RM200_I8259A_IRQ_BASE + 16; i++)
+                set_irq_chip_and_handler(i, &sni_rm200_i8259A_chip,
+                                         handle_level_irq);
+
+        setup_irq(RM200_I8259A_IRQ_BASE + PIC_CASCADE_IR, &sni_rm200_irq2);
+}
+
 
-#define SNI_RM200_INT_STAT_REG  0xbc000000
-#define SNI_RM200_INT_ENA_REG   0xbc080000
+#define SNI_RM200_INT_STAT_REG  CKSEG1ADDR(0xbc000000)
+#define SNI_RM200_INT_ENA_REG   CKSEG1ADDR(0xbc080000)
 
 #define SNI_RM200_INT_START  24
 #define SNI_RM200_INT_END    28
@@ -181,17 +483,17 @@ void __init sni_rm200_irq_init(void)
 
         * (volatile u8 *)SNI_RM200_INT_ENA_REG = 0x1f;
 
+        sni_rm200_i8259_irqs();
         mips_cpu_irq_init();
         /* Actually we've got more interrupts to handle ...  */
         for (i = SNI_RM200_INT_START; i <= SNI_RM200_INT_END; i++)
                 set_irq_chip(i, &rm200_irq_type);
         sni_hwint = sni_rm200_hwint;
         change_c0_status(ST0_IM, IE_IRQ0);
-        setup_irq(SNI_RM200_INT_START + 0, &sni_isa_irq);
+        setup_irq(SNI_RM200_INT_START + 0, &sni_rm200_i8259A_irq);
+        setup_irq(SNI_RM200_INT_START + 1, &sni_isa_irq);
 }
 
 void __init sni_rm200_init(void)
 {
-        set_io_port_base(SNI_PORT_BASE + 0x02000000);
-        ioport_resource.end += 0x02000000;
 }