remoteproc: s/big switch/lookup table/

A lookup table would be easier to extend, and the resulting
code is a bit cleaner.

Reported-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>

diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
index 567a3c5..729911b 100644 (file)
--- a/drivers/remoteproc/remoteproc_core.c
+++ b/drivers/remoteproc/remoteproc_core.c
@@ -64,6 +64,8 @@ static DEFINE_KLIST(rprocs, klist_rproc_get, klist_rproc_put);
 
 typedef int (*rproc_handle_resources_t)(struct rproc *rproc,
                                struct fw_resource *rsc, int len);
+typedef int (*rproc_handle_resource_t)(struct rproc *rproc,
+                               struct fw_resource *rsc);
 
 /*
  * This is the IOMMU fault handler we register with the IOMMU API
@@ -658,44 +660,43 @@ free_mapping:
        return ret;
 }
 
+/*
+ * A lookup table for resource handlers. The indices are defined in
+ * enum fw_resource_type.
+ */
+static rproc_handle_resource_t rproc_handle_rsc[] = {
+       [RSC_CARVEOUT] = rproc_handle_carveout,
+       [RSC_DEVMEM] = rproc_handle_devmem,
+       [RSC_TRACE] = rproc_handle_trace,
+       [RSC_VRING] = rproc_handle_vring,
+       [RSC_VIRTIO_DEV] = NULL, /* handled early upon registration */
+};
+
 /* handle firmware resource entries before booting the remote processor */
 static int
 rproc_handle_boot_rsc(struct rproc *rproc, struct fw_resource *rsc, int len)
 {
        struct device *dev = rproc->dev;
+       rproc_handle_resource_t handler;
        int ret = 0;
 
-       while (len >= sizeof(*rsc)) {
+       for (; len >= sizeof(*rsc); rsc++, len -= sizeof(*rsc)) {
                dev_dbg(dev, "rsc: type %d, da 0x%llx, pa 0x%llx, len 0x%x, "
                        "id %d, name %s, flags %x\n", rsc->type, rsc->da,
                        rsc->pa, rsc->len, rsc->id, rsc->name, rsc->flags);
 
-               switch (rsc->type) {
-               case RSC_CARVEOUT:
-                       ret = rproc_handle_carveout(rproc, rsc);
-                       break;
-               case RSC_DEVMEM:
-                       ret = rproc_handle_devmem(rproc, rsc);
-                       break;
-               case RSC_TRACE:
-                       ret = rproc_handle_trace(rproc, rsc);
-                       break;
-               case RSC_VRING:
-                       ret = rproc_handle_vring(rproc, rsc);
-                       break;
-               case RSC_VIRTIO_DEV:
-                       /* this one is handled early upon registration */
-                       break;
-               default:
+               if (rsc->type >= RSC_LAST) {
                        dev_warn(dev, "unsupported resource %d\n", rsc->type);
-                       break;
+                       continue;
                }
 
+               handler = rproc_handle_rsc[rsc->type];
+               if (!handler)
+                       continue;
+
+               ret = handler(rproc, rsc);
                if (ret)
                        break;
-
-               rsc++;
-               len -= sizeof(*rsc);
        }
 
        return ret;

diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
index b52f784..ada4cb0 100644 (file)
--- a/include/linux/remoteproc.h
+++ b/include/linux/remoteproc.h
@@ -103,6 +103,7 @@ struct fw_resource {
  *                 the virtio device features, 'pa' holds the virtio guest
  *                 features, 'len' holds the virtio status, and 'flags' holds
  *                 the virtio id (currently only VIRTIO_ID_RPMSG is supported).
+ * @RSC_LAST:       just keep this one at the end
  *
  * Most of the resource entries share the basic idea of address/length
  * negotiation with the host: the firmware usually asks (on behalf of the
@@ -115,6 +116,11 @@ struct fw_resource {
  * will contain the expected device addresses (today we actually only support
  * this scheme, as there aren't yet any use cases for dynamically allocated
  * device addresses).
+ *
+ * Please note that these values are used as indices to the rproc_handle_rsc
+ * lookup table, so please keep them sane. Moreover, @RSC_LAST is used to
+ * check the validity of an index before the lookup table is accessed, so
+ * please update it as needed.
  */
 enum fw_resource_type {
        RSC_CARVEOUT    = 0,
@@ -122,6 +128,7 @@ enum fw_resource_type {
        RSC_TRACE       = 2,
        RSC_VRING       = 3,
        RSC_VIRTIO_DEV  = 4,
+       RSC_LAST        = 5,
 };
 
 /**