sfc: SFE4002/SFN4112F: Widen temperature and voltage tolerances

The temperature and voltage limits currently set on these boards are
too conservative and will cause the driver to stop the net device
erroneously in some systems.

Based on a review of the chip datasheets and advice from the designer
of these boards:

- Raise the maximum board temperatures to the specified maximum ambient
  temperatures for their PHYs plus the expected temperature bias of the
  board
- Raise the maximum controller temperature to 90 degrees
- Lower the minimum temperatures to 0 degrees
- Widen the voltage tolerances to at least +/- 10%

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 27 insertions, 18 deletions

diff --git a/drivers/net/sfc/falcon_boards.c b/drivers/net/sfc/falcon_boards.c
index bf0b96af5334..5712fddd72f2 100644
--- a/drivers/net/sfc/falcon_boards.c
+++ b/drivers/net/sfc/falcon_boards.c
@@ -29,6 +29,15 @@
 #define FALCON_BOARD_SFN4111T 0x51
 #define FALCON_BOARD_SFN4112F 0x52
 
+/* Board temperature is about 15°C above ambient when air flow is
+ * limited. */
+#define FALCON_BOARD_TEMP_BIAS  15
+
+/* SFC4000 datasheet says: 'The maximum permitted junction temperature
+ * is 125°C; the thermal design of the environment for the SFC4000
+ * should aim to keep this well below 100°C.' */
+#define FALCON_JUNC_TEMP_MAX    90
+
 /*****************************************************************************
  * Support for LM87 sensor chip used on several boards
  */
@@ -548,16 +557,16 @@ fail_hwmon:
 static u8 sfe4002_lm87_channel = 0x03; /* use AIN not FAN inputs */
 
 static const u8 sfe4002_lm87_regs[] = {
-        LM87_IN_LIMITS(0, 0x83, 0x91),          /* 2.5V:  1.8V +/- 5% */
-        LM87_IN_LIMITS(1, 0x51, 0x5a),          /* Vccp1: 1.2V +/- 5% */
-        LM87_IN_LIMITS(2, 0xb6, 0xca),          /* 3.3V:  3.3V +/- 5% */
-        LM87_IN_LIMITS(3, 0xb0, 0xc9),          /* 5V:    4.6-5.2V */
-        LM87_IN_LIMITS(4, 0xb0, 0xe0),          /* 12V:   11-14V */
-        LM87_IN_LIMITS(5, 0x44, 0x4b),          /* Vccp2: 1.0V +/- 5% */
-        LM87_AIN_LIMITS(0, 0xa0, 0xb2),         /* AIN1:  1.66V +/- 5% */
-        LM87_AIN_LIMITS(1, 0x91, 0xa1),         /* AIN2:  1.5V +/- 5% */
-        LM87_TEMP_INT_LIMITS(10, 60),           /* board */
-        LM87_TEMP_EXT1_LIMITS(10, 70),          /* Falcon */
+        LM87_IN_LIMITS(0, 0x7c, 0x99),          /* 2.5V:  1.8V +/- 10% */
+        LM87_IN_LIMITS(1, 0x4c, 0x5e),          /* Vccp1: 1.2V +/- 10% */
+        LM87_IN_LIMITS(2, 0xac, 0xd4),          /* 3.3V:  3.3V +/- 10% */
+        LM87_IN_LIMITS(3, 0xac, 0xd4),          /* 5V:    5.0V +/- 10% */
+        LM87_IN_LIMITS(4, 0xac, 0xe0),          /* 12V:   10.8-14V */
+        LM87_IN_LIMITS(5, 0x3f, 0x4f),          /* Vccp2: 1.0V +/- 10% */
+        LM87_AIN_LIMITS(0, 0x98, 0xbb),         /* AIN1:  1.66V +/- 10% */
+        LM87_AIN_LIMITS(1, 0x8a, 0xa9),         /* AIN2:  1.5V +/- 10% */
+        LM87_TEMP_INT_LIMITS(0, 80 + FALCON_BOARD_TEMP_BIAS),
+        LM87_TEMP_EXT1_LIMITS(0, FALCON_JUNC_TEMP_MAX),
         0
 };
 
@@ -619,14 +628,14 @@ static int sfe4002_init(struct efx_nic *efx)
 static u8 sfn4112f_lm87_channel = 0x03; /* use AIN not FAN inputs */
 
 static const u8 sfn4112f_lm87_regs[] = {
-        LM87_IN_LIMITS(0, 0x83, 0x91),          /* 2.5V:  1.8V +/- 5% */
-        LM87_IN_LIMITS(1, 0x51, 0x5a),          /* Vccp1: 1.2V +/- 5% */
-        LM87_IN_LIMITS(2, 0xb6, 0xca),          /* 3.3V:  3.3V +/- 5% */
-        LM87_IN_LIMITS(4, 0xb0, 0xe0),          /* 12V:   11-14V */
-        LM87_IN_LIMITS(5, 0x44, 0x4b),          /* Vccp2: 1.0V +/- 5% */
-        LM87_AIN_LIMITS(1, 0x91, 0xa1),         /* AIN2:  1.5V +/- 5% */
-        LM87_TEMP_INT_LIMITS(10, 60),           /* board */
-        LM87_TEMP_EXT1_LIMITS(10, 70),          /* Falcon */
+        LM87_IN_LIMITS(0, 0x7c, 0x99),          /* 2.5V:  1.8V +/- 10% */
+        LM87_IN_LIMITS(1, 0x4c, 0x5e),          /* Vccp1: 1.2V +/- 10% */
+        LM87_IN_LIMITS(2, 0xac, 0xd4),          /* 3.3V:  3.3V +/- 10% */
+        LM87_IN_LIMITS(4, 0xac, 0xe0),          /* 12V:   10.8-14V */
+        LM87_IN_LIMITS(5, 0x3f, 0x4f),          /* Vccp2: 1.0V +/- 10% */
+        LM87_AIN_LIMITS(1, 0x8a, 0xa9),         /* AIN2:  1.5V +/- 10% */
+        LM87_TEMP_INT_LIMITS(0, 60 + FALCON_BOARD_TEMP_BIAS),
+        LM87_TEMP_EXT1_LIMITS(0, FALCON_JUNC_TEMP_MAX),
         0
 };