Merge pull request #55 from PandABlocks/no-min-time

Remove support for .MIN value on time fields

docs/config.rst

@@ -71,7 +71,7 @@ Field
 ``param`` field-subtype [ ``=`` value ]
 ``read`` field-subtype
 ``write`` field-subtype
-``time`` [ ``>`` min_value ]
+``time``
 ``bit_out``
 ``pos_out`` [ scale [ offset [ units ]]]
 ``ext_out`` ( ``timestamp`` | ``samples`` | ``bits`` group )
@@ -96,14 +96,10 @@ Field
     actions on a block.  The `field-subtype` must be specified, and the `action`
     subtype is useful for ``write`` fields which take no data.
 
-``time`` [ ``>`` min_value ]
+``time``
     Time fields behave like ``param`` fields, but need special treatment because
     the underlying value is 64-bits and so two registers need to be written.
 
-    If desired a minimum valid value can be specified as `min_value`.  This will
-    prevent the writing of values less than this value and can be read as the
-    ``.MIN`` attribute.
-
 ``bit_out``
     This identifies an output bit.
 

docs/fields.rst

@@ -127,10 +127,6 @@ Field type          Description
         This attribute can be read or written to report or set the delay in FPGA
         ticks.
 
-    ``MIN``
-        This reports the minimum valid value for this field in the currently
-        selected units.
-
     The ``UNITS`` attribute determines how numbers read or written to the field
     are interpreted.  For example::
 
@@ -466,7 +462,6 @@ scalar          RAW             Underlying integer value                R W
 lut             RAW             Computed Lookup Table 32-bit value      R
 time            UNITS           Units and scaling selection for time    R W C
 \               RAW             Raw time in FPGA clock cycles           R W
-\               MIN             Minimum valid setting (for type only)   R
 bit_out         CAPTURE_WORD    Capturable word containing this bit     R
 \               OFFSET          Offset of this bit in captured word     R
 bit_mux         DELAY           Bit input delay in FPGA ticks           R W C

python/sim_config/registers

@@ -39,8 +39,8 @@ DIV         9
     COUNT           4
 
 PULSE       10
-    DELAY           3 2     >3
-    WIDTH           5 4     >3
+    DELAY           3 2
+    WIDTH           5 4
     INP             0 11
     ENABLE          1 12
     OUT             30 31 32 33

server/time.c

@@ -53,10 +53,6 @@ struct time_class_state {
     unsigned int count;                 // Number of instances of this block
     pthread_mutex_t mutex;              // Interlock for block access
 
-    /* If min_value is set then the range of values [1..min_value] will be
-     * forbidden.  This is used to assist the hardware. */
-    uint64_t min_value;                 // Minimum valid value less 1
-
     struct time_field {
         unsigned int time_scale;        // Scaling factor selection (enum ix)
         uint64_t value;                 // Current value
@@ -104,11 +100,7 @@ static error__t time_parse_register(
     return
         check_parse_register(field, line, &state->low_register)  ?:
         parse_whitespace(line)  ?:
-        check_parse_register(field, line, &state->high_register)  ?:
-        IF(**line != '\0',
-            parse_whitespace(line)  ?:
-            parse_char(line, '>')  ?:
-            parse_uint64(line, &state->min_value));
+        check_parse_register(field, line, &state->high_register);
 }
 
 
@@ -142,23 +134,20 @@ static error__t write_time_value(
     void *class_data, unsigned int number, uint64_t value)
 {
     struct time_class_state *state = class_data;
-    error__t error =
-        TEST_OK_(value == 0  ||  value > state->min_value, "Value too small");
-    if (!error)
-        WITH_MUTEX(state->mutex)
-        {
-            hw_write_register(
-                state->block_base, number, state->low_register,
-                (uint32_t) value);
-            hw_write_register(
-                state->block_base, number, state->high_register,
-                (uint32_t) (value >> 32));
-
-            struct time_field *field = &state->values[number];
-            field->value = value;
-            field->update_index = get_change_index();
-        }
-    return error;
+    WITH_MUTEX(state->mutex)
+    {
+        hw_write_register(
+            state->block_base, number, state->low_register,
+            (uint32_t) value);
+        hw_write_register(
+            state->block_base, number, state->high_register,
+            (uint32_t) (value >> 32));
+
+        struct time_field *field = &state->values[number];
+        field->value = value;
+        field->update_index = get_change_index();
+    }
+    return ERROR_OK;
 }
 
 
@@ -283,19 +272,6 @@ static error__t time_class_units_put(
 }
 
 
-static error__t time_min_format(
-    void *owner, void *class_data, unsigned int number,
-    char result[], size_t length)
-{
-    struct time_class_state *state = class_data;
-    struct time_field *field = &state->values[number];
-    return format_double(
-        result, length,
-        (double) (state->min_value + 1) /
-            time_conversion[field->time_scale] / hw_read_nominal_clock());
-}
-
-
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 /* Time. */
 
@@ -407,9 +383,6 @@ const struct class_methods time_class_methods = {
             .put = time_class_units_put,
             .get_enumeration = time_units_get_enumeration,
         },
-        { "MIN", "Minimum programmable time",
-            .format = time_min_format,
-        },
     ),
 };