commonlib/region: Turn addrspace_32bit into a more official API

We had the addrspace_32bit rdev in prog_loaders.c for a while to help
represent memory ranges as an rdev, and we've found it useful for a
couple of things that have nothing to do with program loading. This
patch moves the concept straight into commonlib/region.c so it is no
longer anchored in such a weird place, and easier to use in unit tests.
Also expand the concept to the whole address space (there's no real need
to restrict it to 32 bits in 64-bit environments) and introduce an
rdev_chain_mem() helper function to make it a bit easier to use. Replace
some direct uses of struct mem_region_device with this new API where it
seems to make sense.

Signed-off-by: Julius Werner <jwerner@chromium.org>
Change-Id: Ie4c763b77f77d227768556a9528681d771a08dca
Reviewed-on: https://review.coreboot.org/c/coreboot/+/52533
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

src/drivers/elog/elog.c

@@ -44,7 +44,7 @@ struct elog_state {
 
 	struct region_device nv_dev;
 	/* Device that mirrors the eventlog in memory. */
-	struct mem_region_device mirror_dev;
+	struct region_device mirror_dev;
 
 	enum elog_init_state elog_initialized;
 };
@@ -56,7 +56,7 @@ static uint8_t elog_mirror_buf[ELOG_SIZE];
 
 static inline struct region_device *mirror_dev_get(void)
 {
-	return &elog_state.mirror_dev.rdev;
+	return &elog_state.mirror_dev;
 }
 
 static size_t elog_events_start(void)
@@ -798,8 +798,7 @@ int elog_init(void)
 		printk(BIOS_ERR, "ELOG: Unable to allocate backing store\n");
 		return -1;
 	}
-	mem_region_device_rw_init(&elog_state.mirror_dev, mirror_buffer,
-				  elog_size);
+	rdev_chain_mem_rw(&elog_state.mirror_dev, mirror_buffer, elog_size);
 
 	/*
 	 * Mark as initialized to allow elog_init() to be called and deemed

src/drivers/intel/gma/opregion.c

@@ -128,16 +128,14 @@ static enum cb_err locate_vbt_vbios(const u8 *vbios, struct region_device *rdev)
 	size_t offset;
 
 	// FIXME: caller should supply a region_device instead of vbios pointer
-	if (rdev_chain(&rd, &addrspace_32bit.rdev, (uintptr_t)vbios,
-	    sizeof(*oprom)))
+	if (rdev_chain_mem(&rd, vbios, sizeof(*oprom)))
 		return CB_ERR;
 
 	if (rdev_readat(&rd, &opromsize, offsetof(optionrom_header_t, size),
 	    sizeof(opromsize)) != sizeof(opromsize) || !opromsize)
 		return CB_ERR;
 
-	if (rdev_chain(&rd, &addrspace_32bit.rdev, (uintptr_t)vbios,
-	    opromsize * 512))
+	if (rdev_chain_mem(&rd, vbios, opromsize * 512))
 		return CB_ERR;
 
 	oprom = rdev_mmap(&rd, 0, sizeof(*oprom));
@@ -200,8 +198,7 @@ static enum cb_err locate_vbt_cbfs(struct region_device *rdev)
 	if (vbt == NULL)
 		return CB_ERR;
 
-	if (rdev_chain(rdev, &addrspace_32bit.rdev, (uintptr_t)vbt,
-	    vbt_data_size))
+	if (rdev_chain_mem(rdev, vbt, vbt_data_size))
 		return CB_ERR;
 
 	printk(BIOS_INFO, "GMA: Found VBT in CBFS\n");

src/drivers/smmstore/store.c

@@ -267,14 +267,14 @@ int smmstore_clear_region(void)
 /* Implementation of Version 2 */
 
 static bool store_initialized;
-static struct mem_region_device mdev_com_buf;
+static struct region_device mdev_com_buf;
 
 static int smmstore_rdev_chain(struct region_device *rdev)
 {
 	if (!store_initialized)
 		return -1;
 
-	return rdev_chain_full(rdev, &mdev_com_buf.rdev);
+	return rdev_chain_full(rdev, &mdev_com_buf);
 }
 
 /**
@@ -289,7 +289,7 @@ int smmstore_init(void *buf, size_t len)
 	if (store_initialized)
 		return -1;
 
-	mem_region_device_rw_init(&mdev_com_buf, buf, len);
+	rdev_chain_mem_rw(&mdev_com_buf, buf, len);
 
 	store_initialized = true;
 

src/drivers/vpd/vpd.c

@@ -101,10 +101,8 @@ static int init_vpd_rdevs_from_cbmem(void)
 	if (!cbmem)
 		return -1;
 
-	rdev_chain(&ro_vpd, &addrspace_32bit.rdev,
-		   (uintptr_t)cbmem->blob, cbmem->ro_size);
-	rdev_chain(&rw_vpd, &addrspace_32bit.rdev,
-		   (uintptr_t)cbmem->blob + cbmem->ro_size, cbmem->rw_size);
+	rdev_chain_mem(&ro_vpd, cbmem->blob, cbmem->ro_size);
+	rdev_chain_mem(&rw_vpd, cbmem->blob + cbmem->ro_size, cbmem->rw_size);
 
 	return 0;
 }