SBE: Add passthrough command support

SBE sends passthrough command. We have to capture this interrupt and
send event to HBRT via opal-prd (user space daemon).

This patch adds minimal SBE code to capture SBE interrupt and send
event to opal-prd. Next patch will add opal-prd (user space) support.

CC: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>

1 files changed, 61 insertions, 0 deletions

diff --git a/hw/sbe-p9.c b/hw/sbe-p9.c
new file mode 100644
index 0000000..c9c3feb
--- /dev/null
+++ b/hw/sbe-p9.c
@@ -0,0 +1,61 @@
+/* Copyright 2017 IBM Corp.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *	http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+ * implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define pr_fmt(fmt) "SBE: " fmt
+
+#include <chip.h>
+#include <errorlog.h>
+#include <lock.h>
+#include <opal.h>
+#include <sbe-p9.h>
+#include <skiboot.h>
+#include <timebase.h>
+#include <timer.h>
+#include <trace.h>
+#include <xscom.h>
+
+void sbe_interrupt(uint32_t chip_id)
+{
+	int rc;
+	u64 data;
+	struct proc_chip *chip;
+
+	chip = get_chip(chip_id);
+	if (chip == NULL)
+		return;
+
+	/* Read doorbell register */
+	rc = xscom_read(chip_id, PSU_HOST_DOORBELL_REG_RW, &data);
+	if (rc) {
+		prlog(PR_ERR, "Failed to read SBE to Host doorbell register "
+		      "[chip id = %x]\n", chip_id);
+		goto clr_interrupt;
+	}
+
+	/* SBE passtrhough command, call prd handler */
+	if (data & SBE_HOST_PASSTHROUGH) {
+		prd_sbe_passthrough(chip_id);
+	}
+
+clr_interrupt:
+	/* Clears all the bits */
+	rc = xscom_write(chip_id, PSU_HOST_DOORBELL_REG_AND,
+			 SBE_HOST_RESPONSE_CLEAR);
+	if (rc) {
+		prlog(PR_ERR, "Failed to clear SBE to Host doorbell "
+		      "register [chip id = %x]\n", chip_id);
+	}
+}