Re: [PATCH] - Increase PNP_MAX_PORT. ACPI devices can have a lot IO resource declarations

Bjorn Helgaas
2007-07-17T16:10:54Z

On Monday 16 July 2007 08:21:07 am Thomas Renninger wrote:
> PNP0C02 devices normally have a lot more IO port declarations than
> currently defined in PNP_MAX_PORT

Yes.

> I also wonder whether other limits like:
> #define PNP_MAX_MEM 4
> #define PNP_MAX_IRQ 2
> #define PNP_MAX_DMA 2
> could get exceeded with pnpacpi?

Definitely. I think the current limits come from the PNP ISA spec
(sec 4.6). I don't see similar limits in the PNPBIOS or ACPI specs,
so ideally I think they should be dynamically allocated as you suggest.

HPET devices often use more than two IRQs, so I worked up the following
patch a while ago. I didn't post it because Adam had plans for a better
fix. But I suspect he's otherwise occupied now :-)

It doesn't change PNP_MAX_PORT, so that would have to be updated.

PNP: increase number of resources devices can use

PNPACPI and PNPBIOS devices can use more than 2 IRQs, so bump PNP_MAX_IRQ
from 2 to 4. For example, HPET devices can have up to 32 timers, each with
an IRQ. (Current HPETs typically have 3 timers.)

Add ISAPNP_MAX_PORT, ISAPNP_MAX_MEM, ISAPNP_MAX_IRQ, and ISAPNP_MAX_DMA
because ISAPNP does limit the number of resources a device can use.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>

Index: work-mm1/drivers/pnp/isapnp/core.c
===================================================================
--- work-mm1.orig/drivers/pnp/isapnp/core.c 2005-08-09 10:07:45.000000000 -0600
+++ work-mm1/drivers/pnp/isapnp/core.c 2005-08-09 14:03:03.000000000 -0600
@@ -950,28 +950,28 @@

dev->active = isapnp_read_byte(ISAPNP_CFG_ACTIVATE);
if (dev->active) {
- for (tmp = 0; tmp < PNP_MAX_PORT; tmp++) {
+ for (tmp = 0; tmp < ISAPNP_MAX_PORT; tmp++) {
ret = isapnp_read_word(ISAPNP_CFG_PORT + (tmp << 1));
if (!ret)
continue;
res->port_resource[tmp].start = ret;
res->port_resource[tmp].flags = IORESOURCE_IO;
}
- for (tmp = 0; tmp < PNP_MAX_MEM; tmp++) {
+ for (tmp = 0; tmp < ISAPNP_MAX_MEM; tmp++) {
ret = isapnp_read_word(ISAPNP_CFG_MEM + (tmp << 3)) << 8;
if (!ret)
continue;
res->mem_resource[tmp].start = ret;
res->mem_resource[tmp].flags = IORESOURCE_MEM;
}
- for (tmp = 0; tmp < PNP_MAX_IRQ; tmp++) {
+ for (tmp = 0; tmp < ISAPNP_MAX_IRQ; tmp++) {
ret = (isapnp_read_word(ISAPNP_CFG_IRQ + (tmp << 1)) >> 8);
if (!ret)
continue;
res->irq_resource[tmp].start = res->irq_resource[tmp].end = ret;
res->irq_resource[tmp].flags = IORESOURCE_IRQ;
}
- for (tmp = 0; tmp < PNP_MAX_DMA; tmp++) {
+ for (tmp = 0; tmp < ISAPNP_MAX_DMA; tmp++) {
ret = isapnp_read_byte(ISAPNP_CFG_DMA + tmp);
if (ret == 4)
continue;
@@ -998,17 +998,17 @@

isapnp_cfg_begin(dev->card->number, dev->number);
dev->active = 1;
- for (tmp = 0; tmp < PNP_MAX_PORT && (res->port_resource[tmp].flags & (IORESOURCE_IO | IORESOURCE_UNSET)) == IORESOURCE_IO; tmp++)
+ for (tmp = 0; tmp < ISAPNP_MAX_PORT && (res->port_resource[tmp].flags & (IORESOURCE_IO | IORESOURCE_UNSET)) == IORESOURCE_IO; tmp++)
isapnp_write_word(ISAPNP_CFG_PORT+(tmp<<1), res->port_resource[tmp].start);
- for (tmp = 0; tmp < PNP_MAX_IRQ && (res->irq_resource[tmp].flags & (IORESOURCE_IRQ | IORESOURCE_UNSET)) == IORESOURCE_IRQ; tmp++) {
+ for (tmp = 0; tmp < ISAPNP_MAX_IRQ && (res->irq_resource[tmp].flags & (IORESOURCE_IRQ | IORESOURCE_UNSET)) == IORESOURCE_IRQ; tmp++) {
int irq = res->irq_resource[tmp].start;
if (irq == 2)
irq = 9;
isapnp_write_byte(ISAPNP_CFG_IRQ+(tmp<<1), irq);
}
- for (tmp = 0; tmp < PNP_MAX_DMA && (res->dma_resource[tmp].flags & (IORESOURCE_DMA | IORESOURCE_UNSET)) == IORESOURCE_DMA; tmp++)
+ for (tmp = 0; tmp < ISAPNP_MAX_DMA && (res->dma_resource[tmp].flags & (IORESOURCE_DMA | IORESOURCE_UNSET)) == IORESOURCE_DMA; tmp++)
isapnp_write_byte(ISAPNP_CFG_DMA+tmp, res->dma_resource[tmp].start);
- for (tmp = 0; tmp < PNP_MAX_MEM && (res->mem_resource[tmp].flags & (IORESOURCE_MEM | IORESOURCE_UNSET)) == IORESOURCE_MEM; tmp++)
+ for (tmp = 0; tmp < ISAPNP_MAX_MEM && (res->mem_resource[tmp].flags & (IORESOURCE_MEM | IORESOURCE_UNSET)) == IORESOURCE_MEM; tmp++)
isapnp_write_word(ISAPNP_CFG_MEM+(tmp<<3), (res->mem_resource[tmp].start >> 8) & 0xffff);
/* FIXME: We aren't handling 32bit mems properly here */
isapnp_activate(dev->number);
Index: work-mm1/include/linux/isapnp.h
===================================================================
--- work-mm1.orig/include/linux/isapnp.h 2005-06-17 13:48:29.000000000 -0600
+++ work-mm1/include/linux/isapnp.h 2005-08-09 14:35:31.000000000 -0600
@@ -24,6 +24,7 @@

#include <linux/config.h>
#include <linux/errno.h>
+#include <linux/kernel.h>
#include <linux/pnp.h>

/*
@@ -36,6 +37,11 @@
#define ISAPNP_CFG_IRQ 0x70 /* 2 * word */
#define ISAPNP_CFG_DMA 0x74 /* 2 * byte */

+#define ISAPNP_MAX_PORT min(8, PNP_MAX_PORT)
+#define ISAPNP_MAX_MEM min(4, PNP_MAX_MEM)
+#define ISAPNP_MAX_IRQ min(2, PNP_MAX_IRQ)
+#define ISAPNP_MAX_DMA min(2, PNP_MAX_DMA)
+
/*
*
*/
Index: work-mm1/include/linux/pnp.h
===================================================================
--- work-mm1.orig/include/linux/pnp.h 2005-08-09 10:07:46.000000000 -0600
+++ work-mm1/include/linux/pnp.h 2005-08-09 14:01:08.000000000 -0600
@@ -16,7 +16,7 @@

#define PNP_MAX_PORT 8
#define PNP_MAX_MEM 4
-#define PNP_MAX_IRQ 2
+#define PNP_MAX_IRQ 4
#define PNP_MAX_DMA 2
#define PNP_NAME_LEN 50

Index: work-mm1/drivers/pnp/pnpacpi/rsparser.c
===================================================================
--- work-mm1.orig/drivers/pnp/pnpacpi/rsparser.c 2005-08-09 10:07:45.000000000 -0600
+++ work-mm1/drivers/pnp/pnpacpi/rsparser.c 2005-08-09 14:29:59.000000000 -0600
@@ -72,6 +72,10 @@
}
}

+/*
+ * ACPI doesn't limit the number of resources a device can use, so
+ * we can use the generic PNP limits (PNP_MAX_IRQ, etc).
+ */
static void
pnpacpi_parse_allocated_irqresource(struct pnp_resource_table * res, u32 gsi,
int edge_level, int active_high_low)
Index: work-mm1/drivers/pnp/pnpbios/rsparser.c
===================================================================
--- work-mm1.orig/drivers/pnp/pnpbios/rsparser.c 2005-08-09 10:07:45.000000000 -0600
+++ work-mm1/drivers/pnp/pnpbios/rsparser.c 2005-08-09 14:29:37.000000000 -0600
@@ -51,6 +51,10 @@
* Allocated Resources
*/

+/*
+ * PNPBIOS doesn't limit the number of resources a device can use, so
+ * we can use the generic PNP limits (PNP_MAX_IRQ, etc).
+ */
static void
pnpbios_parse_allocated_irqresource(struct pnp_resource_table * res, int irq)
{