Add stubs for DPTF thermal thresholds

This adds three new registers to the ACPI->EC interface, which will allow
the AP to set/clear two DPTF thermal threshold points for each temp sensor.

The registers are

  EC_ACPI_MEM_TEMP_ID            0x05
  EC_ACPI_MEM_TEMP_THRESHOLD     0x06
  EC_ACPI_MEM_TEMP_COMMIT        0x07

It doesn't actually do anything yet, but the AP can now write those values.

BUG=chrome-os-partner:23970
BRANCH=none
TEST=manual

On the host:

  dptf() {
         [ "$#" -eq "2" ] || return;
         iotools io_write8 0x66 0x81
         iotools io_write8 0x62 $1
         iotools io_write8 0x62 $2
  }

Now watch the EC console while running on the host:

  dptf 5 1
  dptf 6 80
  dptf 7 2
  dptf 7 3

The EC should say

 DPTF sensor 1, threshold 7 C, index 0, enabled
 DPTF sensor 1, threshold 7 C, index 1, enabled

Change-Id: I71fa57e3ca7c7b5bb8892e63212bf294b44dece5
Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/179778
Reviewed-by: Duncan Laurie <dlaurie@chromium.org>
Reviewed-by: Randall Spangler <rspangler@chromium.org>

4 files changed, 82 insertions, 20 deletions

diff --git a/common/acpi.c b/common/acpi.c
index 942dd21dd2..68c281b6e6 100644
--- a/common/acpi.c
+++ b/common/acpi.c
@@ -20,6 +20,11 @@ static uint8_t acpi_addr;        /* First byte of data after ACPI command */
 static int acpi_data_count;      /* Number of data writes after command */
 static uint8_t acpi_mem_test;    /* Test byte in ACPI memory space */
 
+#ifdef CONFIG_TEMP_SENSOR
+static int dptf_temp_sensor_id;			/* last sensor ID written */
+static int dptf_temp_threshold;			/* last threshold written */
+#endif
+
 /* This handles AP writes to the EC via the ACPI I/O port. There are only a few
  * ACPI commands (EC_CMD_ACPI_*), but they are all handled here.
  */
@@ -27,8 +32,7 @@ int acpi_ap_to_ec(int is_cmd, uint8_t value, uint8_t *resultptr)
 {
 	int data = 0;
 	int retval = 0;
-
-	CPRINTF("[HEY: %T %s(%d, 0x%x)]\n", is_cmd, value);
+	int result = 0xff;			/* value for bogus read */
 
 	/* Read command/data; this clears the FRMH status bit. */
 	if (is_cmd) {
@@ -47,8 +51,6 @@ int acpi_ap_to_ec(int is_cmd, uint8_t value, uint8_t *resultptr)
 	/* Process complete commands */
 	if (acpi_cmd == EC_CMD_ACPI_READ && acpi_data_count == 1) {
 		/* ACPI read cmd + addr */
-		int result = 0xff;		/* value for bogus read */
-
 		switch (acpi_addr) {
 		case EC_ACPI_MEM_VERSION:
 			result = EC_ACPI_MEM_VERSION_CURRENT;
@@ -61,29 +63,20 @@ int acpi_ap_to_ec(int is_cmd, uint8_t value, uint8_t *resultptr)
 			break;
 #ifdef CONFIG_PWM_KBLIGHT
 		case EC_ACPI_MEM_KEYBOARD_BACKLIGHT:
-			/*
-			 * TODO(crosbug.com/p/23774): not very satisfying that
-			 * LPC knows directly about the keyboard backlight, but
-			 * for now this is good enough and less code than
-			 * defining a new API for ACPI commands.  If we start
-			 * adding more commands, or need to support LPC on more
-			 * than just LM4, fix this.
-			 */
 			result = pwm_get_duty(PWM_CH_KBLIGHT);
 			break;
 #endif
 #ifdef CONFIG_FANS
 		case EC_ACPI_MEM_FAN_DUTY:
-			/** TODO(crosbug.com/p/23774): Fix this too */
 			result = dptf_get_fan_duty_target();
 			break;
 #endif
 		default:
+			CPRINTF("[%T ACPI read 0x%02x (ignored)]\n", acpi_addr);
 			break;
 		}
 
 		/* Send the result byte */
-		CPRINTF("[%T ACPI read 0x%02x = 0x%02x]\n", acpi_addr, result);
 		*resultptr = result;
 		retval = 1;
 
@@ -91,7 +84,6 @@ int acpi_ap_to_ec(int is_cmd, uint8_t value, uint8_t *resultptr)
 		/* ACPI write cmd + addr + data */
 		switch (acpi_addr) {
 		case EC_ACPI_MEM_TEST:
-			CPRINTF("[%T ACPI mem test 0x%02x]\n", data);
 			acpi_mem_test = data;
 			break;
 #ifdef CONFIG_PWM_KBLIGHT
@@ -107,12 +99,28 @@ int acpi_ap_to_ec(int is_cmd, uint8_t value, uint8_t *resultptr)
 #endif
 #ifdef CONFIG_FANS
 		case EC_ACPI_MEM_FAN_DUTY:
-			/** TODO(crosbug.com/p/23774): Fix this too */
 			dptf_set_fan_duty_target(data);
 			break;
 #endif
+#ifdef CONFIG_TEMP_SENSOR
+		case EC_ACPI_MEM_TEMP_ID:
+			dptf_temp_sensor_id = data;
+			break;
+		case EC_ACPI_MEM_TEMP_THRESHOLD:
+			dptf_temp_threshold = data + EC_TEMP_SENSOR_OFFSET;
+			break;
+		case EC_ACPI_MEM_TEMP_COMMIT:
+		{
+			int idx = data & EC_ACPI_MEM_TEMP_COMMIT_SELECT_MASK;
+			int enable = data & EC_ACPI_MEM_TEMP_COMMIT_ENABLE_MASK;
+			dptf_set_temp_threshold(dptf_temp_sensor_id,
+						dptf_temp_threshold,
+						idx, enable);
+			break;
+		}
+#endif
 		default:
-			CPRINTF("[%T ACPI write 0x%02x = 0x%02x]\n",
+			CPRINTF("[%T ACPI write 0x%02x = 0x%02x (ignored)]\n",
 				acpi_addr, data);
 			break;
 		}
diff --git a/common/thermal.c b/common/thermal.c
index 97c12412e0..873a8a1981 100644
--- a/common/thermal.c
+++ b/common/thermal.c
@@ -23,6 +23,19 @@
 #define CPUTS(outstr) cputs(CC_THERMAL, outstr)
 #define CPRINTF(format, args...) cprintf(CC_THERMAL, format, ## args)
 
+/*****************************************************************************/
+/* DPTF temperature thresholds */
+
+void dptf_set_temp_threshold(int sensor_id, int temp, int idx, int enable)
+{
+	/* TODO(crosbug.com/p/23970) */
+	CPRINTF("[%T DPTF sensor %d, threshold %d C, index %d, %sabled]\n",
+		sensor_id, K_TO_C(temp), idx, enable ? "en" : "dis");
+}
+
+/*****************************************************************************/
+/* EC-specific thermal controls */
+
 test_mockable_static void smi_sensor_failure_warning(void)
 {
 	CPRINTF("[%T can't read any temp sensors!]\n");
diff --git a/include/dptf.h b/include/dptf.h
index 48be860f2d..4213426255 100644
--- a/include/dptf.h
+++ b/include/dptf.h
@@ -11,7 +11,13 @@
 /* 0-100% sets fixed duty cycle, out of range means let the EC drive */
 void dptf_set_fan_duty_target(int pct);
 
-/*  0-100% if in duty mode. -1 if not */
+/* 0-100% if in duty mode. -1 if not */
 int dptf_get_fan_duty_target(void);
 
+/* Each temp sensor can have up to two thresholds */
+void dptf_set_temp_threshold(int sensor_id,	/* zero-based sensor index */
+			     int temp,		/* in degrees K */
+			     int idx,		/* which threshold (0 or 1) */
+			     int enable);	/* true = on, false = off */
+
 #endif	/* __CROS_EC_DPTF_H */
diff --git a/include/ec_commands.h b/include/ec_commands.h
index b97ef7dc48..7b3fb170d1 100644
--- a/include/ec_commands.h
+++ b/include/ec_commands.h
@@ -1855,6 +1855,7 @@ struct ec_params_reboot_ec {
 #define EC_CMD_ACPI_QUERY_EVENT 0x84
 
 /* Valid addresses in ACPI memory space, for read/write commands */
+
 /* Memory space version; set to EC_ACPI_MEM_VERSION_CURRENT */
 #define EC_ACPI_MEM_VERSION            0x00
 /*
@@ -1864,10 +1865,44 @@ struct ec_params_reboot_ec {
 #define EC_ACPI_MEM_TEST               0x01
 /* Test compliment; writes here are ignored. */
 #define EC_ACPI_MEM_TEST_COMPLIMENT    0x02
+
 /* Keyboard backlight brightness percent (0 - 100) */
 #define EC_ACPI_MEM_KEYBOARD_BACKLIGHT 0x03
-/* Target Fan Duty (0-100, 0xff for auto/none) */
-#define EC_ACPI_MEM_FAN_DUTY 0x04
+/* DPTF Target Fan Duty (0-100, 0xff for auto/none) */
+#define EC_ACPI_MEM_FAN_DUTY           0x04
+
+/*
+ * DPTF temp thresholds. Any of the EC's temp sensors can have up to two
+ * independent thresholds attached to them. The current value of the ID
+ * register determines which sensor is affected by the THRESHOLD and COMMIT
+ * registers. The THRESHOLD register uses the same EC_TEMP_SENSOR_OFFSET scheme
+ * as the memory-mapped sensors. The COMMIT register applies those settings.
+ */
+#define EC_ACPI_MEM_TEMP_ID            0x05
+#define EC_ACPI_MEM_TEMP_THRESHOLD     0x06
+#define EC_ACPI_MEM_TEMP_COMMIT        0x07
+/*
+ * Here are the bits for the COMMIT register:
+ *   bit 0 selects the threshold index for the chosen sensor (0/1)
+ *   bit 1 enables/disables the selected threshold (0 = off, 1 = on)
+ * Each write to the commit register affects one threshold.
+ */
+#define EC_ACPI_MEM_TEMP_COMMIT_SELECT_MASK (1 << 0)
+#define EC_ACPI_MEM_TEMP_COMMIT_ENABLE_MASK (1 << 1)
+/*
+ * Example:
+ *
+ * Set the thresholds for sensor 2 to 50 C and 60 C:
+ *   write 2 to [0x05]      --  select temp sensor 2
+ *   write 0x7b to [0x06]   --  C_TO_K(50) - EC_TEMP_SENSOR_OFFSET
+ *   write 0x2 to [0x07]    --  enable threshold 0 with this value
+ *   write 0x85 to [0x06]   --  C_TO_K(60) - EC_TEMP_SENSOR_OFFSET
+ *   write 0x3 to [0x07]    --  enable threshold 1 with this value
+ *
+ * Disable the 60 C threshold, leaving the 50 C threshold unchanged:
+ *   write 2 to [0x05]      --  select temp sensor 2
+ *   write 0x1 to [0x07]    --  disable threshold 1
+ */
 
 /* Current version of ACPI memory address space */
 #define EC_ACPI_MEM_VERSION_CURRENT 1