Merge tag 'powerpc-6.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:

 - Add HOTPLUG_SMT support (/sys/devices/system/cpu/smt) and honour the
   configured SMT state when hotplugging CPUs into the system

 - Combine final TLB flush and lazy TLB mm shootdown IPIs when using the
   Radix MMU to avoid a broadcast TLBIE flush on exit

 - Drop the exclusion between ptrace/perf watchpoints, and drop the now
   unused associated arch hooks

 - Add support for the "nohlt" command line option to disable CPU idle

 - Add support for -fpatchable-function-entry for ftrace, with GCC >=
   13.1

 - Rework memory block size determination, and support 256MB size on
   systems with GPUs that have hotpluggable memory

 - Various other small features and fixes

Thanks to Andrew Donnellan, Aneesh Kumar K.V, Arnd Bergmann, Athira
Rajeev, Benjamin Gray, Christophe Leroy, Frederic Barrat, Gautam
Menghani, Geoff Levand, Hari Bathini, Immad Mir, Jialin Zhang, Joel
Stanley, Jordan Niethe, Justin Stitt, Kajol Jain, Kees Cook, Krzysztof
Kozlowski, Laurent Dufour, Liang He, Linus Walleij, Mahesh Salgaonkar,
Masahiro Yamada, Michal Suchanek, Nageswara R Sastry, Nathan Chancellor,
Nathan Lynch, Naveen N Rao, Nicholas Piggin, Nick Desaulniers, Omar
Sandoval, Randy Dunlap, Reza Arbab, Rob Herring, Russell Currey, Sourabh
Jain, Thomas Gleixner, Trevor Woerner, Uwe Kleine-König, Vaibhav Jain,
Xiongfeng Wang, Yuan Tan, Zhang Rui, and Zheng Zengkai.

* tag 'powerpc-6.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (135 commits)
  macintosh/ams: linux/platform_device.h is needed
  powerpc/xmon: Reapply "Relax frame size for clang"
  powerpc/mm/book3s64: Use 256M as the upper limit with coherent device memory attached
  powerpc/mm/book3s64: Fix build error with SPARSEMEM disabled
  powerpc/iommu: Fix notifiers being shared by PCI and VIO buses
  powerpc/mpc5xxx: Add missing fwnode_handle_put()
  powerpc/config: Disable SLAB_DEBUG_ON in skiroot
  powerpc/pseries: Remove unused hcall tracing instruction
  powerpc/pseries: Fix hcall tracepoints with JUMP_LABEL=n
  powerpc: dts: add missing space before {
  powerpc/eeh: Use pci_dev_id() to simplify the code
  powerpc/64s: Move CPU -mtune options into Kconfig
  powerpc/powermac: Fix unused function warning
  powerpc/pseries: Rework lppaca_shared_proc() to avoid DEBUG_PREEMPT
  powerpc: Don't include lppaca.h in paca.h
  powerpc/pseries: Move hcall_vphn() prototype into vphn.h
  powerpc/pseries: Move VPHN constants into vphn.h
  cxl: Drop unused detach_spa()
  powerpc: Drop zalloc_maybe_bootmem()
  powerpc/powernv: Use struct opal_prd_msg in more places
  ...

1 files changed, 82 insertions, 3 deletions

diff --git a/drivers/pci/hotplug/rpaphp_pci.c b/drivers/pci/hotplug/rpaphp_pci.c
index 630f77057c23..bcfd26ec6d30 100644
--- a/drivers/pci/hotplug/rpaphp_pci.c
+++ b/drivers/pci/hotplug/rpaphp_pci.c
@@ -19,12 +19,92 @@
 #include "../pci.h"		/* for pci_add_new_bus */
 #include "rpaphp.h"
 
+/*
+ * RTAS call get-sensor-state(DR_ENTITY_SENSE) return values as per PAPR:
+ * -- generic return codes ---
+ *    -1: Hardware Error
+ *    -2: RTAS_BUSY
+ *    -3: Invalid sensor. RTAS Parameter Error.
+ * -- rtas_get_sensor function specific return codes ---
+ * -9000: Need DR entity to be powered up and unisolated before RTAS call
+ * -9001: Need DR entity to be powered up, but not unisolated, before RTAS call
+ * -9002: DR entity unusable
+ *  990x: Extended delay - where x is a number in the range of 0-5
+ */
+#define RTAS_SLOT_UNISOLATED		-9000
+#define RTAS_SLOT_NOT_UNISOLATED	-9001
+#define RTAS_SLOT_NOT_USABLE		-9002
+
+static int rtas_get_sensor_errno(int rtas_rc)
+{
+	switch (rtas_rc) {
+	case 0:
+		/* Success case */
+		return 0;
+	case RTAS_SLOT_UNISOLATED:
+	case RTAS_SLOT_NOT_UNISOLATED:
+		return -EFAULT;
+	case RTAS_SLOT_NOT_USABLE:
+		return -ENODEV;
+	case RTAS_BUSY:
+	case RTAS_EXTENDED_DELAY_MIN...RTAS_EXTENDED_DELAY_MAX:
+		return -EBUSY;
+	default:
+		return rtas_error_rc(rtas_rc);
+	}
+}
+
+/*
+ * get_adapter_status() can be called by the EEH handler during EEH recovery.
+ * On certain PHB failures, the RTAS call rtas_call(get-sensor-state) returns
+ * extended busy error (9902) until PHB is recovered by pHyp. The RTAS call
+ * interface rtas_get_sensor() loops over the RTAS call on extended delay
+ * return code (9902) until the return value is either success (0) or error
+ * (-1). This causes the EEH handler to get stuck for ~6 seconds before it
+ * could notify that the PCI error has been detected and stop any active
+ * operations. This sometimes causes EEH recovery to fail. To avoid this issue,
+ * invoke rtas_call(get-sensor-state) directly if the respective PE is in EEH
+ * recovery state and return -EBUSY error based on RTAS return status. This
+ * will help the EEH handler to notify the driver about the PCI error
+ * immediately and successfully proceed with EEH recovery steps.
+ */
+
+static int __rpaphp_get_sensor_state(struct slot *slot, int *state)
+{
+	int rc;
+	int token = rtas_token("get-sensor-state");
+	struct pci_dn *pdn;
+	struct eeh_pe *pe;
+	struct pci_controller *phb = PCI_DN(slot->dn)->phb;
+
+	if (token == RTAS_UNKNOWN_SERVICE)
+		return -ENOENT;
+
+	/*
+	 * Fallback to existing method for empty slot or PE isn't in EEH
+	 * recovery.
+	 */
+	pdn = list_first_entry_or_null(&PCI_DN(phb->dn)->child_list,
+					struct pci_dn, list);
+	if (!pdn)
+		goto fallback;
+
+	pe = eeh_dev_to_pe(pdn->edev);
+	if (pe && (pe->state & EEH_PE_RECOVERING)) {
+		rc = rtas_call(token, 2, 2, state, DR_ENTITY_SENSE,
+			       slot->index);
+		return rtas_get_sensor_errno(rc);
+	}
+fallback:
+	return rtas_get_sensor(DR_ENTITY_SENSE, slot->index, state);
+}
+
 int rpaphp_get_sensor_state(struct slot *slot, int *state)
 {
 	int rc;
 	int setlevel;
 
-	rc = rtas_get_sensor(DR_ENTITY_SENSE, slot->index, state);
+	rc = __rpaphp_get_sensor_state(slot, state);
 
 	if (rc < 0) {
 		if (rc == -EFAULT || rc == -EEXIST) {
@@ -40,8 +120,7 @@ int rpaphp_get_sensor_state(struct slot *slot, int *state)
 				dbg("%s: power on slot[%s] failed rc=%d.\n",
 				    __func__, slot->name, rc);
 			} else {
-				rc = rtas_get_sensor(DR_ENTITY_SENSE,
-						     slot->index, state);
+				rc = __rpaphp_get_sensor_state(slot, state);
 			}
 		} else if (rc == -ENODEV)
 			info("%s: slot is unusable\n", __func__);