On Fri, 2014-02-21 at 07:37 -0600, Corey Minyard wrote:
> However, the basic problem is that hardware vendors produce hardware
> that sucks and then expect software to fix all the problems. Most IPMI
> interfaces don't have interrupts, so they have to be polled. Then they
> add important interfaces on top of it like firmware upgrade and ACPI and
> expect it to perform well. If vendors would just have an interrupt for
> IPMI, 99% of these problems would go away.
Not going to disagree. The impact on power consumption is also pretty
awful. I should re-read the spec to figure out whether we can
legitimately get away with not doing that.
> One thing we can do is remove the default interface probing for IPMI.
> Even though the spec has it, all modern hardware should have it
> specified in ACPI or device tree. That should fix all the slow boot
> problems, at least. If a user wants to add a default interface, they
> can use the interface to dynamically add it after boot time.
Something like this (untested)?
diff --git a/drivers/char/ipmi/Kconfig b/drivers/char/ipmi/Kconfig
index eea8464..5126230 100644
--- a/drivers/char/ipmi/Kconfig
+++ b/drivers/char/ipmi/Kconfig
@@ -52,6 +52,16 @@ config IPMI_SI
Currently, only KCS and SMIC are supported. If
you are using IPMI, you should probably say "y" here.
+config IPMI_PROBE_DEFAULTS
+ bool 'Probe for all possible IPMI interfaces by default'
+ help
+ Modern systems will usually expose IPMI interfaces via a discoverable
+ firmware mechanism such as ACPI or DMI. Older systems do not, and so
+ the driver is forced to probe hardware manually. This may cause boot
+ delays. Say "n" here to disable this manual probing. IPMI will then
+ only be available on older systems if the "ipmi_si_intf.trydefaults=1"
+ boot argument is passed.
+
config IPMI_WATCHDOG
tristate 'IPMI Watchdog Timer'
help
diff --git a/drivers/char/ipmi/ipmi_si_intf.c b/drivers/char/ipmi/ipmi_si_intf.c
index 03f4189..82c7d56 100644
--- a/drivers/char/ipmi/ipmi_si_intf.c
+++ b/drivers/char/ipmi/ipmi_si_intf.c
@@ -1230,7 +1230,11 @@ static bool si_tryplatform = 1;
#ifdef CONFIG_PCI
static bool si_trypci = 1;
#endif
+#ifdef CONFIG_IPMI_PROBE_DEFAULTS
static bool si_trydefaults = 1;
+#else
+static bool si_trydefaults;
+#endif
static char *si_type[SI_MAX_PARMS];
#define MAX_SI_TYPE_STR 30
static char si_type_str[MAX_SI_TYPE_STR];
--
Matthew Garrett <matthew.garr...@nebula.com>
