ipmi: Add an IPMI command to get and set the RTC

Add IPMI GET_SEL_TIME and SET_SEL_TIME commands to the IPMI stack.

Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 98 insertions, 0 deletions

diff --git a/core/ipmi.c b/core/ipmi.c
index 6cfded6..1278c09 100644
--- a/core/ipmi.c
+++ b/core/ipmi.c
@@ -18,6 +18,98 @@
 #include <bt.h>
 #include <ipmi.h>
 #include <opal.h>
+#include <time.h>
+#include <time-utils.h>
+
+static time_t time = 0;
+
+static void ipmi_process_storage_resp(struct ipmi_msg *msg)
+{
+	uint32_t new_time;
+
+	switch (msg->cmd) {
+	case IPMI_GET_SEL_TIME_CMD:
+		/*
+		 * I couldn't find any mention of endianess in the IPMI spec,
+		 * but ipmitool seemed to assume little endian?
+		 */
+		memcpy(&new_time, msg->resp_data, 4);
+		time = le32_to_cpu(new_time);
+		break;
+
+	case IPMI_SET_SEL_TIME_CMD:
+		/* Nothing to do in this case */
+		break;
+
+	default:
+		printf("Unsupported/invalid IPMI storage command\n");
+	}
+}
+
+static uint32_t time_result;
+static int64_t ipmi_get_sel_time(void)
+{
+	struct ipmi_msg *msg = malloc(sizeof(struct ipmi_msg));
+
+	if (!msg)
+		return OPAL_HARDWARE;
+
+	msg->cmd = IPMI_GET_SEL_TIME_CMD;
+	msg->netfn = IPMI_NETFN_STORAGE_REQUEST;
+	msg->req_data = NULL;
+	msg->req_data_len = 0;
+	msg->resp_data = (uint8_t *) &time_result;
+	msg->resp_data_len = 4;
+	if (bt_add_ipmi_msg_wait(msg))
+		return -1;
+
+	return time_result;
+}
+
+static int64_t ipmi_set_sel_time(uint32_t tv)
+{
+	struct ipmi_msg *msg = malloc(sizeof(struct ipmi_msg));
+
+	if (!msg)
+		return OPAL_HARDWARE;
+
+	msg->cmd = IPMI_SET_SEL_TIME_CMD;
+	msg->netfn = IPMI_NETFN_STORAGE_REQUEST;
+	msg->req_data = (uint8_t *) &tv;
+	msg->req_data_len = 4;
+	msg->resp_data = NULL;
+	msg->resp_data_len = 0;
+
+	return bt_add_ipmi_msg_wait(msg);
+}
+
+static int64_t ipmi_opal_rtc_read(uint32_t *y_m_d,
+				 uint64_t *h_m_s_m)
+{
+	struct tm tm;
+
+	if (ipmi_get_sel_time() < 0)
+		return OPAL_HARDWARE;
+
+	gmtime_r(&time, &tm);
+	tm_to_datetime(&tm, y_m_d, h_m_s_m);
+	return OPAL_SUCCESS;
+}
+
+static int64_t ipmi_opal_rtc_write(uint32_t year_month_day,
+				  uint64_t hour_minute_second_millisecond)
+{
+	time_t t;
+	struct tm tm;
+
+	datetime_to_tm(year_month_day, hour_minute_second_millisecond, &tm);
+	t = mktime(&tm);
+	t = cpu_to_le32(t);
+	if (ipmi_set_sel_time(t))
+		return OPAL_HARDWARE;
+
+	return OPAL_SUCCESS;
+}
 
 static void ipmi_cmd_done(struct ipmi_msg *msg)
 {
@@ -27,6 +119,10 @@ static void ipmi_cmd_done(struct ipmi_msg *msg)
 	}
 
 	switch (msg->netfn) {
+	case IPMI_NETFN_STORAGE_RESPONSE:
+		ipmi_process_storage_resp(msg);
+		break;
+
 	case IPMI_NETFN_CHASSIS_RESPONSE:
 		break;
 	default:
@@ -66,4 +162,6 @@ int64_t ipmi_opal_chassis_control(uint64_t request)
 void ipmi_init(void)
 {
 	bt_init(ipmi_cmd_done);
+	opal_register(OPAL_RTC_READ, ipmi_opal_rtc_read, 2);
+	opal_register(OPAL_RTC_WRITE, ipmi_opal_rtc_write, 2);
 }