powerpc/pseries: Return the number of MSIs we could allocate
If we can't allocate the requested number of MSIs, we can still tell the
generic code how many we were able to allocate. That can then be passed
onto the driver, allowing it to request that many in future, and
probably succeeed.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/platforms/pseries/msi.c b/arch/powerpc/platforms/pseries/msi.c
index e6c80ac..073b518 100644
--- a/arch/powerpc/platforms/pseries/msi.c
+++ b/arch/powerpc/platforms/pseries/msi.c
@@ -71,11 +71,13 @@
} while (rtas_busy_delay(rc));
/*
- * If the RTAS call succeeded, check the number of irqs is actually
- * what we asked for. If not, return an error.
+ * If the RTAS call succeeded, return the number of irqs allocated.
+ * If not, make sure we return a negative error code.
*/
- if (rc == 0 && rtas_ret[0] != num_irqs)
- rc = -ENOSPC;
+ if (rc == 0)
+ rc = rtas_ret[0];
+ else if (rc > 0)
+ rc = -rc;
pr_debug("rtas_msi: ibm,change_msi(func=%d,num=%d), got %d rc = %d\n",
func, num_irqs, rtas_ret[0], rc);
@@ -91,7 +93,7 @@
if (!pdn)
return;
- if (rtas_change_msi(pdn, RTAS_CHANGE_FN, 0))
+ if (rtas_change_msi(pdn, RTAS_CHANGE_FN, 0) != 0)
pr_debug("rtas_msi: Setting MSIs to 0 failed!\n");
}
@@ -195,14 +197,14 @@
if (type == PCI_CAP_ID_MSI) {
rc = rtas_change_msi(pdn, RTAS_CHANGE_MSI_FN, nvec);
- if (rc) {
+ if (rc < 0) {
pr_debug("rtas_msi: trying the old firmware call.\n");
rc = rtas_change_msi(pdn, RTAS_CHANGE_FN, nvec);
}
} else
rc = rtas_change_msi(pdn, RTAS_CHANGE_MSIX_FN, nvec);
- if (rc) {
+ if (rc != nvec) {
pr_debug("rtas_msi: rtas_change_msi() failed\n");
return rc;
}