Re: [PATCH] IPMI: reserve memio regions separately

From: Corey Minyard
Date: Wed Apr 27 2016 - 09:38:30 EST


On 04/27/2016 08:24 AM, Mark Salter wrote:
On Tue, 2016-04-26 at 23:31 -0500, minyard@xxxxxxx wrote:
From: Corey Minyard <cminyard@xxxxxxxxxx>

Commit d61a3ead2680 ("[PATCH] IPMI: reserve I/O ports separately")
changed the way I/O ports were reserved and includes this comment in
log:

Some BIOSes reserve disjoint I/O regions in their ACPI tables for the IPMI
controller. This causes problems when trying to register the entire I/O
region. Therefore we must register each I/O port separately.

There is a similar problem with memio regions on an arm64 platform
(AMD Seattle). Where I see:

ipmi message handler version 39.2
ipmi_si AMDI0300:00: probing via device tree
ipmi_si AMDI0300:00: ipmi_si: probing via ACPI
ipmi_si AMDI0300:00: [mem 0xe0010000] regsize 1 spacing 4 irq 23
ipmi_si: Adding ACPI-specified kcs state machine
IPMI System Interface driver.
ipmi_si: Trying ACPI-specified kcs state machine at mem \
address 0xe0010000, slave address 0x0, irq 23
ipmi_si: Could not set up I/O space

The problem is that the ACPI core registers disjoint regions for the
platform device:

e0010000-e0010000 : AMDI0300:00
e0010004-e0010004 : AMDI0300:00

and the ipmi_si driver tries to register one region e0010000-e0010004.

Based on a patch from Mark Salter <msalter@xxxxxxxxxx>

Signed-off-by: Corey Minyard <cminyard@xxxxxxxxxx>
---
This works for me as well.

Tested-by: Mark Salter <msalter@xxxxxxxxxx>

Thanks a bunch for testing this. Queued for 4.7 and in linux-next.

-corey

drivers/char/ipmi/ipmi_si_intf.c | 40 +++++++++++++++++++++++++++-------------
1 file changed, 27 insertions(+), 13 deletions(-)

diff --git a/drivers/char/ipmi/ipmi_si_intf.c b/drivers/char/ipmi/ipmi_si_intf.c
index 6ecf9af..a815044 100644
--- a/drivers/char/ipmi/ipmi_si_intf.c
+++ b/drivers/char/ipmi/ipmi_si_intf.c
@@ -1637,25 +1637,28 @@ static void mem_outq(const struct si_sm_io *io, unsigned int offset,
}
#endif
-static void mem_cleanup(struct smi_info *info)
+static void mem_region_cleanup(struct smi_info *info, int num)
{
unsigned long addr = info->io.addr_data;
- int mapsize;
+ int idx;
+
+ for (idx = 0; idx < num; idx++)
+ release_mem_region(addr + idx * info->io.regspacing,
+ info->io.regsize);
+}
+static void mem_cleanup(struct smi_info *info)
+{
if (info->io.addr) {
iounmap(info->io.addr);
-
- mapsize = ((info->io_size * info->io.regspacing)
- - (info->io.regspacing - info->io.regsize));
-
- release_mem_region(addr, mapsize);
+ mem_region_cleanup(info, info->io_size);
}
}
static int mem_setup(struct smi_info *info)
{
unsigned long addr = info->io.addr_data;
- int mapsize;
+ int mapsize, idx;
if (!addr)
return -ENODEV;
@@ -1692,6 +1695,21 @@ static int mem_setup(struct smi_info *info)
}
/*
+ * Some BIOSes reserve disjoint memory regions in their ACPI
+ * tables. This causes problems when trying to request the
+ * entire region. Therefore we must request each register
+ * separately.
+ */
+ for (idx = 0; idx < info->io_size; idx++) {
+ if (request_mem_region(addr + idx * info->io.regspacing,
+ info->io.regsize, DEVICE_NAME) == NULL) {
+ /* Undo allocations */
+ mem_region_cleanup(info, idx);
+ return -EIO;
+ }
+ }
+
+ /*
* Calculate the total amount of memory to claim. This is an
* unusual looking calculation, but it avoids claiming any
* more memory than it has to. It will claim everything
@@ -1700,13 +1718,9 @@ static int mem_setup(struct smi_info *info)
*/
mapsize = ((info->io_size * info->io.regspacing)
- (info->io.regspacing - info->io.regsize));
-
- if (request_mem_region(addr, mapsize, DEVICE_NAME) == NULL)
- return -EIO;
-
info->io.addr = ioremap(addr, mapsize);
if (info->io.addr == NULL) {
- release_mem_region(addr, mapsize);
+ mem_region_cleanup(info, info->io_size);
return -EIO;
}
return 0;