sfc: SFE4002/SFN4112F: Widen temperature and voltage tolerances
Ben Hutchings [Fri, 19 Feb 2010 13:34:03 +0000 (13:34 +0000)]
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>

drivers/net/sfc/falcon_boards.c

index bf0b96a..5712fdd 100644 (file)
 #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
 };