npu2-opencapi: Allow platforms to identify physical slots

This patch lets each platform define the name of the opencapi
slots. It makes it easier to identify which physical card is
generating errors or messages in the linux or skiboot log files.

The patch provides slot names for mihawk and witherspoon. If the
platform doesn't define any, then we default to 'OPENCAPI-xxxx'

There are various ways to find out about the slot names:
  skiboot log
  lspci command (if the PCI hotplug driver pnv-php is loaded)
  lshw
  checking the device tree
  and probably others....

Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>

hw/npu2-opencapi.c

@@ -1342,7 +1342,9 @@ static int64_t npu2_opencapi_hreset(struct pci_slot *slot __unused)
 
 static void make_slot_hotpluggable(struct pci_slot *slot, struct phb *phb)
 {
-	char label[40];
+	struct npu2_dev *dev = phb_to_npu2_dev_ocapi(phb);
+	char name[40];
+	const char *label = NULL;
 
 	/*
 	 * Add a few definitions to the DT so that the linux PCI
@@ -1353,8 +1355,16 @@ static void make_slot_hotpluggable(struct pci_slot *slot, struct phb *phb)
 	 */
 	slot->pluggable = 1;
 	pci_slot_add_dt_properties(slot, phb->dt_node);
-	snprintf(label, sizeof(label), "OPENCAPI-%04x",
-		 (int)PCI_SLOT_PHB_INDEX(slot->id));
+
+	if (platform.ocapi->ocapi_slot_label)
+		label = platform.ocapi->ocapi_slot_label(dev->npu->chip_id,
+							 dev->brick_index);
+
+	if (!label) {
+		snprintf(name, sizeof(name), "OPENCAPI-%04x",
+			 (int)PCI_SLOT_PHB_INDEX(slot->id));
+		label = name;
+	}
 	dt_add_property_string(phb->dt_node, "ibm,slot-label", label);
 }
 

include/platform.h

@@ -63,6 +63,7 @@ struct platform_ocapi {
 	uint8_t i2c_presence_brick5;	/* I2C pin to read for presence on brick 5 */
 	bool odl_phy_swap;		/* Swap ODL1 to use brick 2 rather than
 					 * brick 1 lanes */
+	const char *(*ocapi_slot_label)(uint32_t chip_id, uint32_t brick_index);
 };
 
 struct dt_node;

platforms/astbmc/mihawk.c

@@ -55,6 +55,25 @@ static void mihawk_get_slot_info(struct phb *phb, struct pci_device *pd)
 		slot_table_get_slot_info(phb, pd);
 }
 
+static const char *mihawk_ocapi_slot_label(uint32_t chip_id,
+					   uint32_t brick_index)
+{
+	const char *name = NULL;
+
+	if (chip_id == 0) {
+		if (brick_index == 2)
+			name = "JP90NVB1";
+		else
+			name = "JP90NVT1";
+	} else {
+		if (brick_index == 2)
+			name = "JP91NVB1";
+		else
+			name = "JP91NVT1";
+	}
+	return name;
+}
+
 static const struct platform_ocapi mihawk_ocapi = {
         .i2c_engine          = 1,
         .i2c_port            = 4,
@@ -69,6 +88,7 @@ static const struct platform_ocapi mihawk_ocapi = {
         .i2c_presence_brick4 = 0, /* unused */
         .i2c_presence_brick5 = 0, /* unused */
         .odl_phy_swap        = true,
+	.ocapi_slot_label    = mihawk_ocapi_slot_label,
 };
 
 static const struct slot_table_entry P1E1A_x8_PLX8748_down[] = {

platforms/astbmc/witherspoon.c

@@ -325,6 +325,25 @@ static void witherspoon_npu2_device_detect(struct npu2 *npu)
 	return;
 }
 
+static const char *witherspoon_ocapi_slot_label(uint32_t chip_id,
+						uint32_t brick_index)
+{
+	const char *name = NULL;
+
+	if (chip_id == 0) {
+		if (brick_index == 3)
+			name = "OPENCAPI-GPU0";
+		else if (brick_index == 4)
+			name = "OPENCAPI-GPU1";
+	} else {
+		if (brick_index == 3)
+			name = "OPENCAPI-GPU3";
+		else if (brick_index == 4)
+			name = "OPENCAPI-GPU4";
+	}
+	return name;
+}
+
 static const struct platform_ocapi witherspoon_ocapi = {
        .i2c_engine          = 1,
        .i2c_port            = 4,
@@ -348,6 +367,7 @@ static const struct platform_ocapi witherspoon_ocapi = {
        .i2c_presence_brick3 = 0,
        .i2c_presence_brick4 = 0,
        .i2c_presence_brick5 = 0,
+       .ocapi_slot_label    = witherspoon_ocapi_slot_label,
 };
 
 static int gpu_slot_to_num(const char *slot)

platforms/ibm-fsp/zz.c

@@ -15,6 +15,25 @@
 #include "ibm-fsp.h"
 #include "lxvpd.h"
 
+static const char *zz_ocapi_slot_label(uint32_t chip_id,
+				       uint32_t brick_index)
+{
+	const char *name = NULL;
+
+	if (chip_id == 0) {
+		if (brick_index == 2)
+			name = "P1-T5";
+		else
+			name = "P1-T6";
+	} else {
+		if (brick_index == 2)
+			name = "P1-T7";
+		else
+			name = "P1-T8";
+	}
+	return name;
+}
+
 /* We don't yet create NPU device nodes on ZZ, but these values are correct */
 static const struct platform_ocapi zz_ocapi = {
 	.i2c_engine          = 1,
@@ -30,6 +49,7 @@ static const struct platform_ocapi zz_ocapi = {
 	.i2c_presence_brick4 = 0, /* unused */
 	.i2c_presence_brick5 = 0, /* unused */
 	.odl_phy_swap        = true,
+	.ocapi_slot_label    = zz_ocapi_slot_label,
 };
 
 #define NPU_BASE 0x5011000