[PATCH v3 2/2] cxl: Configure the PSL for two CAPI ports on POWER8NVL

[Philippe Bergheaud <felix@linux.vnet.ibm.com>]

The POWER8NVL chip has two CAPI ports.  Configure the PSL to route
data to the port corresponding to the CAPP unit.

Signed-off-by: Philippe Bergheaud <felix@linux.vnet.ibm.com>
---
V2:
  - Complete rewrite after Mikey's review
V3:
  Fixes suggested by Michael:
  - s/capp_unit_id(/get_capp_unit_id(/
  - Fix block commenting style
  - Remove extra space
  - Use of_property_read_u32
  - Add blank line after return
  - Fix logic for phb_index > 1 on POWERNVL
  - s/cappunitid/capp_unit_id/
  - Add error message for -ENODEV

 drivers/misc/cxl/pci.c | 41 ++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 40 insertions(+), 1 deletion(-)

diff --git a/drivers/misc/cxl/pci.c b/drivers/misc/cxl/pci.c
index 2844e97..94fd3f7 100644
--- a/drivers/misc/cxl/pci.c
+++ b/drivers/misc/cxl/pci.c
@@ -21,6 +21,7 @@
 #include <asm/msi_bitmap.h>
 #include <asm/pnv-pci.h>
 #include <asm/io.h>
+#include <asm/reg.h>
 
 #include "cxl.h"
 #include <misc/cxl.h>
@@ -321,12 +322,43 @@ static void dump_afu_descriptor(struct cxl_afu *afu)
 #undef show_reg
 }
 
+#define CAPP_UNIT0_ID 0xBA
+#define CAPP_UNIT1_ID 0XBE
+
+static u64 get_capp_unit_id(struct device_node *np)
+{
+	u32 phb_index;
+
+	/*
+	 * For chips other than POWER8NVL, we only have CAPP 0,
+	 * irrespective of which PHB is used.
+	 */
+	if (!pvr_version_is(PVR_POWER8NVL))
+		return CAPP_UNIT0_ID;
+
+	/*
+	 * For POWER8NVL, assume CAPP 0 is attached to PHB0 and
+	 * CAPP 1 is attached to PHB1.
+	 */
+	if (of_property_read_u32(np, "ibm,phb-index", &phb_index))
+		return 0;
+
+	if (phb_index == 0)
+		return CAPP_UNIT0_ID;
+
+	if (phb_index == 1)
+		return CAPP_UNIT1_ID;
+
+	return 0;
+}
+
 static int init_implementation_adapter_regs(struct cxl *adapter, struct pci_dev *dev)
 {
 	struct device_node *np;
 	const __be32 *prop;
 	u64 psl_dsnctl;
 	u64 chipid;
+	u64 capp_unit_id;
 
 	if (!(np = pnv_pci_get_phb_node(dev)))
 		return -ENODEV;
@@ -336,10 +368,17 @@ static int init_implementation_adapter_regs(struct cxl *adapter, struct pci_dev
 	if (!np)
 		return -ENODEV;
 	chipid = be32_to_cpup(prop);
+	capp_unit_id = get_capp_unit_id(np);
 	of_node_put(np);
+	if (!capp_unit_id) {
+		pr_err("cxl: invalid capp unit id\n");
+		return -ENODEV;
+	}
 
 	/* Tell PSL where to route data to */
-	psl_dsnctl = 0x02E8900002000000ULL | (chipid << (63-5));
+	psl_dsnctl = 0x0000900002000000ULL | (chipid << (63-5));
+	psl_dsnctl |= (capp_unit_id << (63-13));
+
 	cxl_p1_write(adapter, CXL_PSL_DSNDCTL, psl_dsnctl);
 	cxl_p1_write(adapter, CXL_PSL_RESLCKTO, 0x20000000200ULL);
 	/* snoop write mask */
-- 
2.1.0