[PATCH 1/6] powerpc/mpic: Fix use of "flags" variable in mpic_alloc()

From: Kyle Moffett
Date: Thu Dec 22 2011 - 15:20:26 EST


The mpic_alloc() function takes a "flags" parameter and assigns it into
the mpic->flags variable fairly early on, but several later pieces of
code detect various device-tree properties and save them into the
"mpic->flags" variable (EG: "big-endian" => MPIC_BIG_ENDIAN).

Unfortunately, a number of codepaths (including several which test the
flag MPIC_BIG_ENDIAN!) test "flags" instead of "mpic->flags", and get
wrong answers as a result.

Consolidate the device-tree flag tests early in mpic_alloc() and change
all of the checks after "mpic->flags" is init'ed to use "mpic->flags".

Signed-off-by: Kyle Moffett <Kyle.D.Moffett@xxxxxxxxxx>
---
arch/powerpc/sysdev/mpic.c | 46 +++++++++++++++++++++----------------------
1 files changed, 22 insertions(+), 24 deletions(-)

diff --git a/arch/powerpc/sysdev/mpic.c b/arch/powerpc/sysdev/mpic.c
index 4e9ccb1..9dd7f76 100644
--- a/arch/powerpc/sysdev/mpic.c
+++ b/arch/powerpc/sysdev/mpic.c
@@ -1182,6 +1182,14 @@ struct mpic * __init mpic_alloc(struct device_node *node,
}
}

+ /* Read extra device-tree properties into the flags variable */
+ if (of_get_property(mpic->node, "big-endian", NULL))
+ flags |= MPIC_BIG_ENDIAN;
+ if (of_get_property(mpic->node, "pic-no-reset", NULL))
+ flags |= MPIC_NO_RESET;
+ if (of_device_is_compatible(mpic->node, "fsl,mpic"))
+ flags |= MPIC_FSL;
+
mpic = kzalloc(sizeof(struct mpic), GFP_KERNEL);
if (mpic == NULL)
goto err_of_node_put;
@@ -1189,15 +1197,16 @@ struct mpic * __init mpic_alloc(struct device_node *node,
mpic->name = name;
mpic->node = node;
mpic->paddr = phys_addr;
+ mpic->flags = flags;

mpic->hc_irq = mpic_irq_chip;
mpic->hc_irq.name = name;
- if (!(flags & MPIC_SECONDARY))
+ if (!(mpic->flags & MPIC_SECONDARY))
mpic->hc_irq.irq_set_affinity = mpic_set_affinity;
#ifdef CONFIG_MPIC_U3_HT_IRQS
mpic->hc_ht_irq = mpic_irq_ht_chip;
mpic->hc_ht_irq.name = name;
- if (!(flags & MPIC_SECONDARY))
+ if (!(mpic->flags & MPIC_SECONDARY))
mpic->hc_ht_irq.irq_set_affinity = mpic_set_affinity;
#endif /* CONFIG_MPIC_U3_HT_IRQS */

@@ -1209,12 +1218,11 @@ struct mpic * __init mpic_alloc(struct device_node *node,
mpic->hc_tm = mpic_tm_chip;
mpic->hc_tm.name = name;

- mpic->flags = flags;
mpic->isu_size = isu_size;
mpic->irq_count = irq_count;
mpic->num_sources = 0; /* so far */

- if (flags & MPIC_LARGE_VECTORS)
+ if (mpic->flags & MPIC_LARGE_VECTORS)
intvec_top = 2047;
else
intvec_top = 255;
@@ -1233,12 +1241,6 @@ struct mpic * __init mpic_alloc(struct device_node *node,
mpic->ipi_vecs[3] = intvec_top - 1;
mpic->spurious_vec = intvec_top;

- /* Check for "big-endian" in device-tree */
- if (of_get_property(mpic->node, "big-endian", NULL) != NULL)
- mpic->flags |= MPIC_BIG_ENDIAN;
- if (of_device_is_compatible(mpic->node, "fsl,mpic"))
- mpic->flags |= MPIC_FSL;
-
/* Look for protected sources */
psrc = of_get_property(mpic->node, "protected-sources", &psize);
if (psrc) {
@@ -1254,11 +1256,11 @@ struct mpic * __init mpic_alloc(struct device_node *node,
}

#ifdef CONFIG_MPIC_WEIRD
- mpic->hw_set = mpic_infos[MPIC_GET_REGSET(flags)];
+ mpic->hw_set = mpic_infos[MPIC_GET_REGSET(mpic->flags)];
#endif

/* default register type */
- if (flags & MPIC_BIG_ENDIAN)
+ if (mpic->flags & MPIC_BIG_ENDIAN)
mpic->reg_type = mpic_access_mmio_be;
else
mpic->reg_type = mpic_access_mmio_le;
@@ -1268,10 +1270,10 @@ struct mpic * __init mpic_alloc(struct device_node *node,
* only if the kernel includes DCR support.
*/
#ifdef CONFIG_PPC_DCR
- if (flags & MPIC_USES_DCR)
+ if (mpic->flags & MPIC_USES_DCR)
mpic->reg_type = mpic_access_dcr;
#else
- BUG_ON(flags & MPIC_USES_DCR);
+ BUG_ON(mpic->flags & MPIC_USES_DCR);
#endif

/* Map the global registers */
@@ -1283,10 +1285,7 @@ struct mpic * __init mpic_alloc(struct device_node *node,
/* When using a device-node, reset requests are only honored if the MPIC
* is allowed to reset.
*/
- if (of_get_property(mpic->node, "pic-no-reset", NULL))
- mpic->flags |= MPIC_NO_RESET;
-
- if ((flags & MPIC_WANTS_RESET) && !(mpic->flags & MPIC_NO_RESET)) {
+ if ((mpic->flags & MPIC_WANTS_RESET) && !(mpic->flags & MPIC_NO_RESET)) {
printk(KERN_DEBUG "mpic: Resetting\n");
mpic_write(mpic->gregs, MPIC_INFO(GREG_GLOBAL_CONF_0),
mpic_read(mpic->gregs, MPIC_INFO(GREG_GLOBAL_CONF_0))
@@ -1297,12 +1296,12 @@ struct mpic * __init mpic_alloc(struct device_node *node,
}

/* CoreInt */
- if (flags & MPIC_ENABLE_COREINT)
+ if (mpic->flags & MPIC_ENABLE_COREINT)
mpic_write(mpic->gregs, MPIC_INFO(GREG_GLOBAL_CONF_0),
mpic_read(mpic->gregs, MPIC_INFO(GREG_GLOBAL_CONF_0))
| MPIC_GREG_GCONF_COREINT);

- if (flags & MPIC_ENABLE_MCK)
+ if (mpic->flags & MPIC_ENABLE_MCK)
mpic_write(mpic->gregs, MPIC_INFO(GREG_GLOBAL_CONF_0),
mpic_read(mpic->gregs, MPIC_INFO(GREG_GLOBAL_CONF_0))
| MPIC_GREG_GCONF_MCK);
@@ -1313,7 +1312,7 @@ struct mpic * __init mpic_alloc(struct device_node *node,
*/
greg_feature = mpic_read(mpic->gregs, MPIC_INFO(GREG_FEATURE_0));
if (isu_size == 0) {
- if (flags & MPIC_BROKEN_FRR_NIRQS)
+ if (mpic->flags & MPIC_BROKEN_FRR_NIRQS)
mpic->num_sources = mpic->irq_count;
else
mpic->num_sources =
@@ -1347,8 +1346,7 @@ struct mpic * __init mpic_alloc(struct device_node *node,

mpic->irqhost = irq_alloc_host(mpic->node, IRQ_HOST_MAP_LINEAR,
isu_size ? isu_size : mpic->num_sources,
- &mpic_host_ops,
- flags & MPIC_LARGE_VECTORS ? 2048 : 256);
+ &mpic_host_ops, intvec_top + 1);

/*
* FIXME: The code leaks the MPIC object and mappings here; this
@@ -1383,7 +1381,7 @@ struct mpic * __init mpic_alloc(struct device_node *node,
mpic->next = mpics;
mpics = mpic;

- if (!(flags & MPIC_SECONDARY)) {
+ if (!(mpic->flags & MPIC_SECONDARY)) {
mpic_primary = mpic;
irq_set_default_host(mpic->irqhost);
}
--
1.7.7.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/