- Set have_message in interrupt to handle "response before READ" case

- Serialize access to property channel when using bcm2835_mbox_property

diff --git a/sys/arm/broadcom/bcm2835/bcm2835_mbox.c b/sys/arm/broadcom/bcm2835/bcm2835_mbox.c
index 5f75fd4ae46b795b7a0b3dd831ecca8b4dbcd7ab..221bccc66a930d4350ff4588e69c2d82c722216e 100644 (file)
--- a/sys/arm/broadcom/bcm2835/bcm2835_mbox.c
+++ b/sys/arm/broadcom/bcm2835/bcm2835_mbox.c
@@ -34,6 +34,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/lock.h>
 #include <sys/module.h>
 #include <sys/mutex.h>
+#include <sys/sx.h>
 #include <sys/rman.h>
 #include <machine/bus.h>
 
@@ -83,6 +84,7 @@ struct bcm_mbox_softc {
        bus_space_handle_t      bsh;
        int                     msg[BCM2835_MBOX_CHANS];
        int                     have_message[BCM2835_MBOX_CHANS];
+       struct sx               property_chan_lock;
 };
 
 #define        mbox_read_4(sc, reg)            \
@@ -122,8 +124,10 @@ bcm_mbox_intr(void *arg)
 
        MBOX_LOCK(sc);
        while (!(mbox_read_4(sc, REG_STATUS) & STATUS_EMPTY))
-               if (bcm_mbox_read_msg(sc, &chan) == 0)
+               if (bcm_mbox_read_msg(sc, &chan) == 0) {
+                       sc->have_message[chan] = 1;
                        wakeup(&sc->have_message[chan]);
+               }
        MBOX_UNLOCK(sc);
 }
 
@@ -179,6 +183,8 @@ bcm_mbox_attach(device_t dev)
                sc->have_message[i] = 0;
        }
 
+       sx_init(&sc->property_chan_lock, "mboxprop");
+
        /* Read all pending messages */
        while ((mbox_read_4(sc, REG_STATUS) & STATUS_EMPTY) == 0)
                (void)mbox_read_4(sc, REG_READ);
@@ -366,6 +372,7 @@ bcm2835_mbox_err(device_t dev, bus_addr_t msg_phys, uint32_t resp_phys,
 int
 bcm2835_mbox_property(void *msg, size_t msg_size)
 {
+       struct bcm_mbox_softc *sc;
        struct msg_set_power_state *buf;
        bus_dma_tag_t msg_tag;
        bus_dmamap_t msg_map;
@@ -379,11 +386,16 @@ bcm2835_mbox_property(void *msg, size_t msg_size)
        if (mbox == NULL)
                return (ENXIO);
 
+       sc = device_get_softc(mbox);
+       sx_xlock(&sc->property_chan_lock);
+
        /* Allocate memory for the message */
        buf = bcm2835_mbox_init_dma(mbox, msg_size, &msg_tag, &msg_map,
            &msg_phys);
-       if (buf == NULL)
-               return (ENOMEM);
+       if (buf == NULL) {
+               err = ENOMEM;
+               goto out;
+       }
 
        memcpy(buf, msg, msg_size);
 
@@ -404,7 +416,8 @@ bcm2835_mbox_property(void *msg, size_t msg_size)
        bus_dmamap_unload(msg_tag, msg_map);
        bus_dmamem_free(msg_tag, buf, msg_map);
        bus_dma_tag_destroy(msg_tag);
-
+out:
+       sx_xunlock(&sc->property_chan_lock);
        return (err);
 }