[PATCH HACK] powerpc: quick hack to get a functional eHEA with
hardirq preemption

Sebastien Dugue

to:

15.09.2008 10:07

Cc:

linux-ppc, linux-kernel, Linux-rt, netdev, Jan-Bernd Themann, Thomas
Q Klein, Christoph Raisch, jean-pierre.dion, gilles.carry, tinytim


WARNING: HACK - HACK - HACK
Not-Signed-off-by: Sebastien Dugue [off-list ref]
---

--- a/arch/powerpc/kernel/ibmebus.c
+++ b/arch/powerpc/kernel/ibmebus.c

@@ -41,6 +41,7 @@
-   return request_irq(irq, handler, irq_flags, devname, dev_id);
+   ret = request_irq(irq, handler, irq_flags, devname, dev_id);
+
+   desc = irq_desc + irq;
+   desc->status &= ~(IRQ_TYPE_SENSE_MASK | IRQ_LEVEL);
+   desc->status |= IRQ_TYPE_EDGE_RISING;
+
+   return ret;

 }
 EXPORT_SYMBOL(ibmebus_request_irq);

diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index b7b397a..6d366ca 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c

@@ -430,7 +430,7 @@ handle_fasteoi_irq(unsigned int irq, struct

irq_desc *desc)
    action = desc->action;
    if (unlikely(!action || (desc->status & (IRQ_INPROGRESS |
                    IRQ_DISABLED)))) {
-      desc->status |= IRQ_PENDING;
+      desc->status |= IRQ_PENDING | IRQ_MASKED;
       if (desc->chip->mask)
          desc->chip->mask(irq);
       goto out;

@@ -439,9 +439,10 @@ handle_fasteoi_irq(unsigned int irq, struct

irq_desc *desc)
    desc->status |= IRQ_INPROGRESS;
    /*
     * In the threaded case we fall back to a mask+eoi sequence:
+    * excepted for edge interrupts which are not masked.
     */
    if (redirect_hardirq(desc)) {
-      if (desc->chip->mask)
+      if (desc->chip->mask && !(desc->status & IRQ_TYPE_EDGE_BOTH))
          desc->chip->mask(irq);
       goto out;
    }

diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 3bffa20..3e39c71 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c

@@ -788,9 +788,12 @@ static void do_hardirq(struct irq_desc *desc)
       thread_simple_irq(desc);
    else if (desc->handle_irq == handle_level_irq)
       thread_level_irq(desc);
-   else if (desc->handle_irq == handle_fasteoi_irq)
-      thread_fasteoi_irq(desc);
-   else if (desc->handle_irq == handle_edge_irq)
+   else if (desc->handle_irq == handle_fasteoi_irq) {
+      if (desc->status & IRQ_TYPE_EDGE_BOTH)
+         thread_edge_irq(desc);
+      else
+         thread_fasteoi_irq(desc);
+   } else if (desc->handle_irq == handle_edge_irq)
       thread_edge_irq(desc);
    else
       thread_do_irq(desc);
--

1.6.0.1.308.gede4c