linux/arch/powerpc/sysdev/mpc8xx_pic.c
Julia Lawall b1725c9319 [POWERPC] arch/powerpc/sysdev: Add missing of_node_put
The functions of_find_compatible_node and of_find_node_by_type both
call of_node_get on their result.  So any error handling code
thereafter should call of_node_put(np).  This is taken care of in the
case where there is a goto out, but not when there is a direct return.

The function irq_alloc_host puts np into the returned structure, which is
stored in the global variable mpc8xx_pic_host, so the reference count
should be set for the lifetime of that variable.  The current solution ups
the reference count again in the argument to irq_alloc_host so that it can
be decremented on the way out.  This seems a bit unnecessary, and also
doesn't work in the case where irq_alloc_host fails, because then the
reference count only goes does by one, whereas it should go down by two.  A
better solution is to not increment the reference count in the argument to
irq_alloc_host and only decrement it on the way out in an error case.

The problem was found using the following semantic match.
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@
type T,T1,T2;
identifier E;
statement S;
expression x1,x2,x3;
int ret;
@@

  T E;
  ...
* E = \(of_get_parent\|of_find_compatible_node\)(...);
  if (E == NULL) S
  ... when != of_node_put(...,(T1)E,...)
      when != if (E != NULL) { ... of_node_put(...,(T1)E,...); ...}
      when != x1 = (T1)E
      when != E = x3;
      when any
  if (...) {
    ... when != of_node_put(...,(T2)E,...)
        when != if (E != NULL) { ... of_node_put(...,(T2)E,...); ...}
        when != x2 = (T2)E
(
*   return;
|
*   return ret;
)
  }
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Kumar Gala <galak@gate.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-02-06 22:06:59 +11:00

195 lines
4.3 KiB
C

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/stddef.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/signal.h>
#include <linux/irq.h>
#include <linux/dma-mapping.h>
#include <asm/prom.h>
#include <asm/irq.h>
#include <asm/io.h>
#include <asm/8xx_immap.h>
#include "mpc8xx_pic.h"
#define PIC_VEC_SPURRIOUS 15
extern int cpm_get_irq(struct pt_regs *regs);
static struct irq_host *mpc8xx_pic_host;
#define NR_MASK_WORDS ((NR_IRQS + 31) / 32)
static unsigned long ppc_cached_irq_mask[NR_MASK_WORDS];
static sysconf8xx_t __iomem *siu_reg;
int cpm_get_irq(struct pt_regs *regs);
static void mpc8xx_unmask_irq(unsigned int virq)
{
int bit, word;
unsigned int irq_nr = (unsigned int)irq_map[virq].hwirq;
bit = irq_nr & 0x1f;
word = irq_nr >> 5;
ppc_cached_irq_mask[word] |= (1 << (31-bit));
out_be32(&siu_reg->sc_simask, ppc_cached_irq_mask[word]);
}
static void mpc8xx_mask_irq(unsigned int virq)
{
int bit, word;
unsigned int irq_nr = (unsigned int)irq_map[virq].hwirq;
bit = irq_nr & 0x1f;
word = irq_nr >> 5;
ppc_cached_irq_mask[word] &= ~(1 << (31-bit));
out_be32(&siu_reg->sc_simask, ppc_cached_irq_mask[word]);
}
static void mpc8xx_ack(unsigned int virq)
{
int bit;
unsigned int irq_nr = (unsigned int)irq_map[virq].hwirq;
bit = irq_nr & 0x1f;
out_be32(&siu_reg->sc_sipend, 1 << (31-bit));
}
static void mpc8xx_end_irq(unsigned int virq)
{
int bit, word;
unsigned int irq_nr = (unsigned int)irq_map[virq].hwirq;
bit = irq_nr & 0x1f;
word = irq_nr >> 5;
ppc_cached_irq_mask[word] |= (1 << (31-bit));
out_be32(&siu_reg->sc_simask, ppc_cached_irq_mask[word]);
}
static int mpc8xx_set_irq_type(unsigned int virq, unsigned int flow_type)
{
struct irq_desc *desc = get_irq_desc(virq);
desc->status &= ~(IRQ_TYPE_SENSE_MASK | IRQ_LEVEL);
desc->status |= flow_type & IRQ_TYPE_SENSE_MASK;
if (flow_type & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW))
desc->status |= IRQ_LEVEL;
if (flow_type & IRQ_TYPE_EDGE_FALLING) {
irq_hw_number_t hw = (unsigned int)irq_map[virq].hwirq;
unsigned int siel = in_be32(&siu_reg->sc_siel);
/* only external IRQ senses are programmable */
if ((hw & 1) == 0) {
siel |= (0x80000000 >> hw);
out_be32(&siu_reg->sc_siel, siel);
desc->handle_irq = handle_edge_irq;
}
}
return 0;
}
static struct irq_chip mpc8xx_pic = {
.typename = " MPC8XX SIU ",
.unmask = mpc8xx_unmask_irq,
.mask = mpc8xx_mask_irq,
.ack = mpc8xx_ack,
.eoi = mpc8xx_end_irq,
.set_type = mpc8xx_set_irq_type,
};
unsigned int mpc8xx_get_irq(void)
{
int irq;
/* For MPC8xx, read the SIVEC register and shift the bits down
* to get the irq number.
*/
irq = in_be32(&siu_reg->sc_sivec) >> 26;
if (irq == PIC_VEC_SPURRIOUS)
irq = NO_IRQ;
return irq_linear_revmap(mpc8xx_pic_host, irq);
}
static int mpc8xx_pic_host_map(struct irq_host *h, unsigned int virq,
irq_hw_number_t hw)
{
pr_debug("mpc8xx_pic_host_map(%d, 0x%lx)\n", virq, hw);
/* Set default irq handle */
set_irq_chip_and_handler(virq, &mpc8xx_pic, handle_level_irq);
return 0;
}
static int mpc8xx_pic_host_xlate(struct irq_host *h, struct device_node *ct,
u32 *intspec, unsigned int intsize,
irq_hw_number_t *out_hwirq, unsigned int *out_flags)
{
static unsigned char map_pic_senses[4] = {
IRQ_TYPE_EDGE_RISING,
IRQ_TYPE_LEVEL_LOW,
IRQ_TYPE_LEVEL_HIGH,
IRQ_TYPE_EDGE_FALLING,
};
*out_hwirq = intspec[0];
if (intsize > 1 && intspec[1] < 4)
*out_flags = map_pic_senses[intspec[1]];
else
*out_flags = IRQ_TYPE_NONE;
return 0;
}
static struct irq_host_ops mpc8xx_pic_host_ops = {
.map = mpc8xx_pic_host_map,
.xlate = mpc8xx_pic_host_xlate,
};
int mpc8xx_pic_init(void)
{
struct resource res;
struct device_node *np;
int ret;
np = of_find_compatible_node(NULL, NULL, "fsl,pq1-pic");
if (np == NULL)
np = of_find_node_by_type(NULL, "mpc8xx-pic");
if (np == NULL) {
printk(KERN_ERR "Could not find fsl,pq1-pic node\n");
return -ENOMEM;
}
ret = of_address_to_resource(np, 0, &res);
if (ret)
goto out;
siu_reg = ioremap(res.start, res.end - res.start + 1);
if (siu_reg == NULL) {
ret = -EINVAL;
goto out;
}
mpc8xx_pic_host = irq_alloc_host(np, IRQ_HOST_MAP_LINEAR,
64, &mpc8xx_pic_host_ops, 64);
if (mpc8xx_pic_host == NULL) {
printk(KERN_ERR "MPC8xx PIC: failed to allocate irq host!\n");
ret = -ENOMEM;
goto out;
}
return 0;
out:
of_node_put(np);
return ret;
}