Changeset 409a996 in mainline

Timestamp:

2013-04-03T16:49:52Z (12 years ago)

Author:

Beniamino Galvani <b.galvani@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

f22f679

Parents:

44b2b78

Message:

bcm2835: improve interrupt handling

File:

• kernel/genarch/include/genarch/drivers/bcm2835/irc.h (modified) (2 diffs)

kernel/genarch/include/genarch/drivers/bcm2835/irc.h

@@ -51 +51 @@
 #define BCM2835_UART_IRQ        MAKE_IRQ(BANK_GPU1, 25)
 #define BCM2835_TIMER1_IRQ      MAKE_IRQ(BANK_GPU0,  1)
+
+#define IRQ_PEND_ARM_M          0xFF
+#define IRQ_PEND_GPU0_M         (1 << 8)
+#define IRQ_PEND_GPU1_M         (1 << 9)
+#define IRQ_PEND_SHORT_M        0x1FFC00
+#define IRQ_PEND_SHORT_S        10
+
+unsigned shortcut_inums[] = {7, 9, 10, 18, 19, 53, 54, 55, 56, 57, 62};
 
 typedef struct {
@@ -111 +119 @@
 {
         uint32_t pending;
-
-        /* TODO: use 'shortcut' bits in basic pending register */
+        int inum = -1;
 
         pending = regs->irq_basic_pending;
-        if (pending & 0xff)
-                return MAKE_IRQ(BANK_ARM, ffs(pending & 0xFF) - 1);
 
-        pending = regs->irq_pending1;
-        if (pending)
-                return MAKE_IRQ(BANK_GPU0, ffs(pending) - 1);
+        /*
+         * The basic pending register shows interrupts pending from ARM
+         * peripherals and it also contains, in order to speed up processing,
+         * additional information about pending GPU interrupts:
+         *
+         *  - bits 0-7 are associated to ARM peripherals
+         *  - bit 8 is 1 when at least one bit is set in pending register 1
+         *  - bit 9 is 1 when at least one bit is set in pending register 2
+         *  - bits 10-20 indicate pending status of selected GPU peripherals
+         *
+         *  Reference: BCM2835 ARM Peripherals, p.113
+         */
 
-        pending = regs->irq_pending2;
-        if (pending)
-                return MAKE_IRQ(BANK_GPU1, ffs(pending) - 1);
+        if (pending & IRQ_PEND_ARM_M) {
+                inum = MAKE_IRQ(BANK_ARM, ffs(pending & IRQ_PEND_ARM_M) - 1);
+        } else if (pending & IRQ_PEND_SHORT_M) {
+                int pos = (pending & IRQ_PEND_SHORT_M) >> IRQ_PEND_SHORT_S;
+                inum = shortcut_inums[ffs(pos) - 1];
+        } else if (pending & IRQ_PEND_GPU0_M) {
+                inum = MAKE_IRQ(BANK_GPU0, ffs(regs->irq_pending1) - 1);
+        } else if (pending & IRQ_PEND_GPU1_M) {
+                inum = MAKE_IRQ(BANK_GPU1, ffs(regs->irq_pending2) - 1);
+        }
 
-        printf("Spurious interrupt!\n");
-        bcm2835_irc_dump(regs);
-        return 0;
+        if (inum < 0) {
+                printf("Spurious interrupt!\n");
+                bcm2835_irc_dump(regs);
+                inum = 0;
+        }
+
+        return inum;
 }