powerpc: Enable relocation on during exceptions at boot
We currently do this synchronously at boot from setup_arch. On a large
system this could hypothetically take a little while to complete, so
currently we will give up if we are asked to wait for more than a second
in total.
If we actually start hitting that timeout in practice we can always move
this code into a kernel thread to take care of it in the background.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index e1a5b8a..5d97553 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -367,6 +367,36 @@
}
}
+/*
+ * Enable relocation on during exceptions. This has partition wide scope and
+ * may take a while to complete, if it takes longer than one second we will
+ * just give up rather than wasting any more time on this - if that turns out
+ * to ever be a problem in practice we can move this into a kernel thread to
+ * finish off the process later in boot.
+ */
+static int __init pSeries_enable_reloc_on_exc(void)
+{
+ long rc;
+ unsigned int delay, total_delay = 0;
+
+ while (1) {
+ rc = enable_reloc_on_exceptions();
+ if (!H_IS_LONG_BUSY(rc))
+ return rc;
+
+ delay = get_longbusy_msecs(rc);
+ total_delay += delay;
+ if (total_delay > 1000) {
+ pr_warn("Warning: Giving up waiting to enable "
+ "relocation on exceptions (%u msec)!\n",
+ total_delay);
+ return rc;
+ }
+
+ mdelay(delay);
+ }
+}
+
static void __init pSeries_setup_arch(void)
{
panic_timeout = 10;
@@ -402,6 +432,14 @@
ppc_md.enable_pmcs = pseries_lpar_enable_pmcs;
else
ppc_md.enable_pmcs = power4_enable_pmcs;
+
+ if (firmware_has_feature(FW_FEATURE_SET_MODE)) {
+ long rc;
+ if ((rc = pSeries_enable_reloc_on_exc()) != H_SUCCESS) {
+ pr_warn("Unable to enable relocation on exceptions: "
+ "%ld\n", rc);
+ }
+ }
}
static int __init pSeries_init_panel(void)