Port-arm archive
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]
Re: Some issues on Sheevaplug
>Using my Sheevaplug and NetBSD, I encountered three issues :
>- When I use the serial console for a long time, my Sheevaplug hangs up
(nothing to report with OpenSSH).
The problem is with the interrupt system.
On the kirkwood series of chips there are two interrupt cause registers - a
low one and a high one.
kirkwood.c splits the high and low register up into two pics with the high
register pic being chained off the low register pic on BIT0 (MainHighSum)
this is incorrect as masking off this bit does not stop interrupts on the
high register from firing. The correct way of doing this is to have one pic
for both registers.
The reason the serial console hangs is that the processor is trying to
execute atomic functions (atomic_or_32) in pic_mark_pending_sources which
restart when returning from an interrupt (LOCK_CAS) and since the high
register interrupt is not being masked off the atomic functions never
complete as they are constantly being interrupted with interrupts from the
UART.
Most of the time this isnt an issue as the current design establishes the
"high register interrupt" as IPL_HIGH and is allowed to run the high
register interrupt handler and block the relevant high interrupt bit -
however when running other IPL_HIGH code it just masks off BIT0
(MainHighSum) in the low register and marks it as pending and doesnt
immediately run the high register interrupt handler.
The code uses a single pic for low and high registers:
Index: kirkwood.c
===================================================================
RCS file: /cvsroot/src/sys/arch/arm/marvell/kirkwood.c,v
retrieving revision 1.2
diff -u -r1.2 kirkwood.c
--- kirkwood.c 30 Oct 2010 06:37:49 -0000 1.2
+++ kirkwood.c 10 Mar 2011 15:44:32 -0000
@@ -49,12 +49,8 @@
static void kirkwood_intr_init(void);
-static void kirkwood_pic_unblock_low_irqs(struct pic_softc *, size_t,
uint32_t);
-static void kirkwood_pic_unblock_high_irqs(struct pic_softc *, size_t,
- uint32_t);
-static void kirkwood_pic_block_low_irqs(struct pic_softc *, size_t,
uint32_t);
-static void kirkwood_pic_block_high_irqs(struct pic_softc *, size_t,
uint32_t);
-static int kirkwood_pic_find_pending_high_irqs(struct pic_softc *);
+static void kirkwood_pic_unblock_irqs(struct pic_softc *, size_t,
uint32_t);
+static void kirkwood_pic_block_irqs(struct pic_softc *, size_t, uint32_t);
static void kirkwood_pic_establish_irq(struct pic_softc *, struct
intrsource *);
static void kirkwood_pic_source_name(struct pic_softc *, int, char *,
size_t);
@@ -80,31 +76,18 @@
"Reserved(60)", "Reserved(61)", "Reserved(62)", "Reserved(63)"
};
-static struct pic_ops kirkwood_picops_low = {
- .pic_unblock_irqs = kirkwood_pic_unblock_low_irqs,
- .pic_block_irqs = kirkwood_pic_block_low_irqs,
+static struct pic_ops kirkwood_picops = {
+ .pic_unblock_irqs = kirkwood_pic_unblock_irqs,
+ .pic_block_irqs = kirkwood_pic_block_irqs,
.pic_establish_irq = kirkwood_pic_establish_irq,
.pic_source_name = kirkwood_pic_source_name,
};
-static struct pic_ops kirkwood_picops_high = {
- .pic_unblock_irqs = kirkwood_pic_unblock_high_irqs,
- .pic_block_irqs = kirkwood_pic_block_high_irqs,
- .pic_find_pending_irqs = kirkwood_pic_find_pending_high_irqs,
- .pic_establish_irq = kirkwood_pic_establish_irq,
- .pic_source_name = kirkwood_pic_source_name,
-};
-static struct pic_softc kirkwood_pic_low = {
- .pic_ops = &kirkwood_picops_low,
- .pic_maxsources = 32,
- .pic_name = "kirkwood_low",
-};
-static struct pic_softc kirkwood_pic_high = {
- .pic_ops = &kirkwood_picops_high,
- .pic_maxsources = 32,
- .pic_name = "kirkwood_high",
+static struct pic_softc kirkwood_pic = {
+ .pic_ops = &kirkwood_picops,
+ .pic_maxsources = 64,
+ .pic_name = "kirkwood",
};
-
/*
* kirkwood_intr_bootstrap:
*
@@ -141,12 +124,7 @@
extern struct pic_softc mvsoc_bridge_pic;
void *ih;
- pic_add(&kirkwood_pic_low, 0);
-
- pic_add(&kirkwood_pic_high, 32);
- ih = intr_establish(KIRKWOOD_IRQ_HIGH, IPL_HIGH, IST_LEVEL_HIGH,
- pic_handle_intr, &kirkwood_pic_high);
- KASSERT(ih != NULL);
+ pic_add(&kirkwood_pic, 0);
pic_add(&mvsoc_bridge_pic, 64);
ih = intr_establish(KIRKWOOD_IRQ_BRIDGE, IPL_HIGH, IST_LEVEL_HIGH,
@@ -158,55 +136,32 @@
/* ARGSUSED */
static void
-kirkwood_pic_unblock_low_irqs(struct pic_softc *pic, size_t irqbase,
+kirkwood_pic_unblock_irqs(struct pic_softc *pic, size_t irqbase,
uint32_t irq_mask)
{
-
- write_mlmbreg(KIRKWOOD_MLMB_MIRQIMLR,
- read_mlmbreg(KIRKWOOD_MLMB_MIRQIMLR) | irq_mask);
+ if (irqbase == 0)
+ write_mlmbreg(KIRKWOOD_MLMB_MIRQIMLR,
+ read_mlmbreg(KIRKWOOD_MLMB_MIRQIMLR) | irq_mask);
+ else if (irqbase == 32)
+ write_mlmbreg(KIRKWOOD_MLMB_MIRQIMHR,
+ read_mlmbreg(KIRKWOOD_MLMB_MIRQIMHR) | irq_mask);
+ else
+ KASSERT(0);
}
/* ARGSUSED */
static void
-kirkwood_pic_unblock_high_irqs(struct pic_softc *pic, size_t irqbase,
- uint32_t irq_mask)
-{
-
- write_mlmbreg(KIRKWOOD_MLMB_MIRQIMHR,
- read_mlmbreg(KIRKWOOD_MLMB_MIRQIMHR) | irq_mask);
-}
-
-/* ARGSUSED */
-static void
-kirkwood_pic_block_low_irqs(struct pic_softc *pic, size_t irqbase,
+kirkwood_pic_block_irqs(struct pic_softc *pic, size_t irqbase,
uint32_t irq_mask)
{
-
- write_mlmbreg(KIRKWOOD_MLMB_MIRQIMLR,
- read_mlmbreg(KIRKWOOD_MLMB_MIRQIMLR) & ~irq_mask);
-}
-
-/* ARGSUSED */
-static void
-kirkwood_pic_block_high_irqs(struct pic_softc *pic, size_t irqbase,
- uint32_t irq_mask)
-{
-
- write_mlmbreg(KIRKWOOD_MLMB_MIRQIMHR,
- read_mlmbreg(KIRKWOOD_MLMB_MIRQIMHR) & ~irq_mask);
-}
-
-static int
-kirkwood_pic_find_pending_high_irqs(struct pic_softc *pic)
-{
- uint32_t pending;
-
- pending = read_mlmbreg(KIRKWOOD_MLMB_MICHR) &
- read_mlmbreg(KIRKWOOD_MLMB_MIRQIMHR);
- if (pending == 0)
- return 0;
- pic_mark_pending_sources(pic, 0, pending);
- return 1;
+ if (irqbase == 0)
+ write_mlmbreg(KIRKWOOD_MLMB_MIRQIMLR,
+ read_mlmbreg(KIRKWOOD_MLMB_MIRQIMLR) & ~irq_mask);
+ else if (irqbase == 32)
+ write_mlmbreg(KIRKWOOD_MLMB_MIRQIMHR,
+ read_mlmbreg(KIRKWOOD_MLMB_MIRQIMHR) & ~irq_mask);
+ else
+ KASSERT(0);
}
/* ARGSUSED */
@@ -229,14 +184,25 @@
static int
kirkwood_find_pending_irqs(void)
{
- uint32_t pending;
+ uint32_t pendinglow, causelowreg;
+ uint32_t pendinghigh = 0, ipl_masklow = 0, ipl_maskhigh = 0;
- pending = read_mlmbreg(KIRKWOOD_MLMB_MICLR) &
+ causelowreg = read_mlmbreg(KIRKWOOD_MLMB_MICLR);
+ pendinglow = causelowreg &
read_mlmbreg(KIRKWOOD_MLMB_MIRQIMLR);
- if (pending == 0)
- return 0;
- return pic_mark_pending_sources(&kirkwood_pic_low, 0, pending);
+ if ((causelowreg & KIRKWOOD_IRQ_HIGH)==KIRKWOOD_IRQ_HIGH)
+ {
+ pendinghigh = read_mlmbreg(KIRKWOOD_MLMB_MICHR) &
+ read_mlmbreg(KIRKWOOD_MLMB_MIRQIMHR);
+ }
+
+ if (pendinglow != 0)
+ ipl_masklow = pic_mark_pending_sources(&kirkwood_pic, 0,
pendinglow);
+ if (pendinghigh !=0)
+ ipl_maskhigh = pic_mark_pending_sources(&kirkwood_pic, 32,
pendinghigh);
+
+ return (ipl_masklow | ipl_maskhigh);
}
/*
--
View this message in context:
http://old.nabble.com/Some-issues-on-Sheevaplug-tp30822756p31117056.html
Sent from the port-arm mailing list archive at Nabble.com.
Home |
Main Index |
Thread Index |
Old Index