SD bugfixes

Detail:
* Implement SD activity LED for Pi 4
* Remove inappropriate reprogramming of GPIO47 for Pi 3 B(+) and A+
* Correct the value for SDHCIWriteInterval which is used during SetSDCLK()

VersionNum

@@ -4,18 +4,18 @@
  *
  */
 #define Module_MajorVersion_CMHG        0.82
-#define Module_MinorVersion_CMHG        Pi4.5
+#define Module_MinorVersion_CMHG        Pi4.6
 #define Module_Date_CMHG                18 Feb 2020
 
 #define Module_MajorVersion             "0.82"
 #define Module_Version                  82
-#define Module_MinorVersion             "Pi4.5"
+#define Module_MinorVersion             "Pi4.6"
 #define Module_Date                     "18 Feb 2020"
 
 #define Module_ApplicationDate          "18-Feb-20"
 
 #define Module_ComponentName            "HAL_BCM2835"
 
-#define Module_FullVersion              "0.82 (Pi4.5)"
-#define Module_HelpVersion              "0.82 (18 Feb 2020) Pi4.5"
+#define Module_FullVersion              "0.82 (Pi4.6)"
+#define Module_HelpVersion              "0.82 (18 Feb 2020) Pi4.6"
 #define Module_LibraryVersionInfo       "0:82"

s/SDIO

@@ -71,16 +71,17 @@ GPIO_CLK                *       48
 GPIO_CD_AB              *       47  ; needs pull-up; active low
 GPIO_STATUS_LED_AB      *       16  ; active low
 GPIO_STATUS_LED_BPlus   *       47  ; active high
+GPIO_STATUS_LED_B4      *       42  ; active high
 
 ; GPIO function select bitfields
 GPIO_FSEL_INPUT  *      0
 GPIO_FSEL_OUTPUT *      1
-GPIO_FSEL_ALT0   *      2
-GPIO_FSEL_ALT1   *      3
-GPIO_FSEL_ALT2   *      4
-GPIO_FSEL_ALT3   *      5
-GPIO_FSEL_ALT4   *      6
-GPIO_FSEL_ALT5   *      7
+GPIO_FSEL_ALT0   *      4
+GPIO_FSEL_ALT1   *      5
+GPIO_FSEL_ALT2   *      6
+GPIO_FSEL_ALT3   *      7
+GPIO_FSEL_ALT4   *      3
+GPIO_FSEL_ALT5   *      2
 GPIO_FSEL_SHIFT  *      3
 GPIO_FSEL_MASK   *      7
 
@@ -352,7 +353,7 @@ SDIO_InitDevices ROUT
         CMP     a3, #BoardRevision_Model_APlus
         TEQ     a3, #BoardRevision_Model_Compute
         TEQNE   a3, #BoardRevision_Model_Compute3
-02      ; So now LO => model A or B, EQ => Compute or Compute3, HI => A+, B+ or Pi 2 or Pi 3 or Pi 0
+02      ; So now LO => model A or B, EQ => Compute or Compute3, HI => A+, B+ or Pi 2 or Pi 3 or Pi 0 or Pi 4
 
         ; Activate
         ADRLO   a1, Activate_AB
@@ -402,9 +403,19 @@ SDIO_InitDevices ROUT
         TEQNE   a3, #BoardRevision_Model_B3Plus
         TEQNE   a3, #BoardRevision_Model_A3Plus
         ADREQL  a1, SetActivity_B3
+        TEQ     a3, #BoardRevision_Model_B4
+        ADREQL  a1, SetActivity_B4
         STR     a1, SDHCIDevice + HALDevice_SDHCISetActivity
         STR     a2, SDHCIDevice + HALDevice_SDHCIGetCardDetect
 
+        ; Don't do pin muxing in Activate for any of these boards either
+        TEQ     a3, #BoardRevision_Model_B3
+        TEQNE   a3, #BoardRevision_Model_B3Plus
+        TEQNE   a3, #BoardRevision_Model_A3Plus
+        TEQNE   a3, #BoardRevision_Model_B4
+        ADREQ   a1, Activate_Compute
+        STREQ   a1, SDHCIDevice + HALDevice_Activate
+
         MOV     a1, #0 ; flags
         ADR     a2, SDHCIDevice
         Pull    "lr"
@@ -722,7 +733,7 @@ SetSDCLK ROUT
         ; Set a long gap between writes while we're fiddling with the SDCLK
         MOV     a1, #MIN_SDCLK
         BL      CalcTimings
-        STR     a1, SDHCIWriteInterval
+        STR     v1, SDHCIWriteInterval
 
         ; Calculate desired values
         MOV     a1, a3
@@ -870,6 +881,21 @@ SetActivity_B3 ROUT
         STR     a2, [a1]
         Pull    "sb,pc"
 
+SetActivity_B4 ROUT
+        Push    "sb,lr"
+        DoMemBarrier lr ; switch to GPIO peripheral
+        SUB     sb, a1, #:INDEX:SDHCIDevice
+
+        ; Line is active high
+        ASSERT  HALDeviceSDHCI_ActivityOff = 0
+        MOVS    a2, a3
+        MOVNE   a2, #1
+        MOV     a1, #GPIO_STATUS_LED_B4
+        BL      GPIO_Output
+
+        DoMemBarrier lr ; back to SDHCI peripheral
+        Pull    "sb,pc"
+
 GetCardDetect_AB ROUT
         Push    "sb,lr"
         DoMemBarrier lr ; switch to GPIO peripheral