phb3/capi: Add two new modes to opal_pci_set_phb_capi_mode

For user initiated capp recovery, provide a mode to turn snoops off.  The perst
alone does not turn snoops off and we need to do this as part of the capp
recovery procedure before reinitializing the phb.

A second mode turns snoops back on after recovery.  The driver needs to do this
after it reinitializes the PSL otherwise tlbies could come in before the psl is
initialized.  Also write 0 to capp error status and control as part of the
recovery procedure.

Put modes as flag defines in opal.h so the driver can pick them up.

Add a dt property "ibm,capi-modes" which tells the driver which modes sapphire
supports.  For backwards compatibility with older opals.  Also, the driver can
disable reset in sysfs if not supported.

Move the mode checking into phb3.c so it's all in one place.

Signed-off-by: Ryan Grimm <grimm@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

3 files changed, 44 insertions, 12 deletions

diff --git a/core/pci-opal.c b/core/pci-opal.c
index 2048d7f..47c9377 100644
--- a/core/pci-opal.c
+++ b/core/pci-opal.c
@@ -703,15 +703,10 @@ static int64_t opal_pci_set_phb_capi_mode(uint64_t phb_id, uint64_t mode, uint64
 		return OPAL_PARAMETER;
 	if (!phb->ops->set_capi_mode)
 		return OPAL_UNSUPPORTED;
-	if (mode == 1) {
-		phb->ops->lock(phb);
-		rc = phb->ops->set_capi_mode(phb, mode, pe_number);
-		phb->ops->unlock(phb);
-		return rc;
-	}
-	if (mode == 0) {
-		/* FIXME add support for PCI mode*/
-	}
-	return OPAL_UNSUPPORTED;
+
+	phb->ops->lock(phb);
+	rc = phb->ops->set_capi_mode(phb, mode, pe_number);
+	phb->ops->unlock(phb);
+	return rc;
 }
 opal_call(OPAL_PCI_SET_PHB_CAPI_MODE, opal_pci_set_phb_capi_mode, 3);
diff --git a/hw/phb3.c b/hw/phb3.c
index fec2071..3c03c20 100644
--- a/hw/phb3.c
+++ b/hw/phb3.c
@@ -2916,8 +2916,37 @@ static int64_t phb3_set_capi_mode(struct phb *phb, uint64_t mode,
 	uint64_t reg;
 	int i;
 
-	if (mode != 1)
-		return OPAL_PARAMETER;
+	xscom_read(p->chip_id, CAPP_ERR_STATUS_CTRL, &reg);
+	if ((reg & PPC_BIT(5))) {
+		PHBERR(p, "CAPP recovery failed (%016llx)\n", reg);
+		return OPAL_HARDWARE;
+	} else if ((reg & PPC_BIT(0)) && (!(reg & PPC_BIT(1)))) {
+		PHBDBG(p, "CAPP recovery in progress\n");
+		return OPAL_BUSY;
+	}
+
+	if (mode == OPAL_PHB_MODE_PCIE)
+		return OPAL_UNSUPPORTED;
+
+	if (mode == OPAL_PHB_MODE_SNOOP_OFF) {
+		xscom_write(p->chip_id, SNOOP_CAPI_CONFIG, 	0x0000000000000000);
+		return OPAL_SUCCESS;
+	}
+
+	if (mode == OPAL_PHB_MODE_SNOOP_ON) {
+		xscom_write(p->chip_id, CAPP_ERR_STATUS_CTRL,  	0x0000000000000000);
+		xscom_write(p->chip_id, SNOOP_CAPI_CONFIG, 	0xA1F0000000000000);
+		return OPAL_SUCCESS;
+	}
+
+	if (mode != OPAL_PHB_MODE_CAPI)
+		return OPAL_UNSUPPORTED;
+
+	xscom_read(p->chip_id, 0x9013c03, &reg);
+	if (reg & PPC_BIT(0)) {
+		PHBDBG(p, "Already in CAPP mode\n");
+		return OPAL_SUCCESS;
+	}
 
 	if (!p->capp_ucode_loaded) {
 		PHBERR(p, "capp ucode not loaded into capp unit\n");
@@ -4087,6 +4116,9 @@ static void phb3_probe_pbcq(struct dt_node *pbcq)
 	}
 	max_link_speed = dt_prop_get_u32_def(pbcq, "ibm,max-link-speed", 3);
 	dt_add_property_cells(np, "ibm,max-link-speed", max_link_speed);
+	dt_add_property_cells(np, "ibm,capi-modes", OPAL_PHB_MODE_CAPI |
+							OPAL_PHB_MODE_SNOOP_ON |
+							OPAL_PHB_MODE_SNOOP_OFF);
 
 	add_chip_dev_associativity(np);
 }
diff --git a/include/opal.h b/include/opal.h
index 99a3335..7046fb2 100644
--- a/include/opal.h
+++ b/include/opal.h
@@ -871,6 +871,11 @@ struct opal_sg_list {
 #define OPAL_DUMP_REGION_OS_START		0x80
 #define OPAL_DUMP_REGION_OS_END			0xFF
 
+/* CAPI flags */
+#define OPAL_PHB_MODE_PCIE		0x00000000
+#define OPAL_PHB_MODE_CAPI		0x00000001
+#define OPAL_PHB_MODE_SNOOP_OFF		0x00000002
+#define OPAL_PHB_MODE_SNOOP_ON		0x00000004
 
 /****** Internal **********/
 #include <skiboot.h>