sdhci: add optional quirk property to disable card insertion/removal interrupts

This is needed for a quirk of the Raspberry Pi (bcm2835/6) MMC
controller, where the card insert bit is documented as unimplemented
(always reads zero, doesn't generate interrupts) but is in fact
observed on hardware as set at power on, but is cleared (and remains
clear) on subsequent controller resets.
Signed-off-by: NAndrew Baumann <Andrew.Baumann@microsoft.com>
Reviewed-by: NPeter Crosthwaite <crosthwaite.peter@gmail.com>
Message-id: 1450738069-18664-4-git-send-email-Andrew.Baumann@microsoft.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

hw/sd/sdhci.c

@@ -193,7 +193,9 @@ static void sdhci_reset(SDHCIState *s)
      * initialization */
     memset(&s->sdmasysad, 0, (uintptr_t)&s->capareg - (uintptr_t)&s->sdmasysad);
 
-    sd_set_cb(s->card, s->ro_cb, s->eject_cb);
+    if (!s->noeject_quirk) {
+        sd_set_cb(s->card, s->ro_cb, s->eject_cb);
+    }
     s->data_count = 0;
     s->stopped_state = sdhc_not_stopped;
 }
@@ -1276,6 +1278,7 @@ static Property sdhci_sysbus_properties[] = {
     DEFINE_PROP_UINT32("capareg", SDHCIState, capareg,
             SDHC_CAPAB_REG_DEFAULT),
     DEFINE_PROP_UINT32("maxcurr", SDHCIState, maxcurr, 0),
+    DEFINE_PROP_BOOL("noeject-quirk", SDHCIState, noeject_quirk, false),
     DEFINE_PROP_END_OF_LIST(),
 };
 

include/hw/sd/sdhci.h

@@ -77,6 +77,7 @@ typedef struct SDHCIState {
     uint32_t buf_maxsz;
     uint16_t data_count;   /* current element in FIFO buffer */
     uint8_t  stopped_state;/* Current SDHC state */
+    bool     noeject_quirk;/* Quirk to disable card insert/remove interrupts */
     /* Buffer Data Port Register - virtual access point to R and W buffers */
     /* Software Reset Register - always reads as 0 */
     /* Force Event Auto CMD12 Error Interrupt Reg - write only */