CBMEM: Clarify CBMEM_TOP_BACKUP function usage

The deprecated LATE_CBMEM_INIT function is renamed:
  set_top_of_ram -> set_late_cbmem_top

Obscure term top_of_ram is replaced:
  backup_top_of_ram -> backup_top_of_low_cacheable
  get_top_of_ram -> restore_top_of_low_cacheable

New function that always resolves to CBMEM top boundary, with
or without SMM, is named restore_cbmem_top().

Change-Id: I61d20f94840ad61e9fd55976e5aa8c27040b8fb7
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/19377
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Philippe Mathieu-Daudé <philippe.mathieu.daude@gmail.com>

src/northbridge/intel/e7505/northbridge.c

@@ -92,7 +92,7 @@ static void pci_domain_set_resources(device_t dev)
 				(remaplimitk + 64*1024) - remapbasek);
 		}
 
-		set_top_of_ram(tolmk * 1024);
+		set_late_cbmem_top(tolmk * 1024);
 	}
 	assign_resources(dev->link_list);
 }

src/northbridge/intel/e7505/raminit.c

@@ -1892,10 +1892,10 @@ void e7505_mch_init(const struct mem_controller *memctrl)
 	sdram_enable(memctrl);
 }
 
-unsigned long get_top_of_ram(void)
+uintptr_t restore_top_of_low_cacheable(void)
 {
 	u32 tolm = (pci_read_config16(MCHDEV, TOLM) & ~0x7ff) << 16;
-	return (unsigned long) tolm;
+	return tolm;
 }
 
 /**

src/northbridge/intel/i3100/northbridge.c

@@ -119,7 +119,7 @@ static void pci_domain_set_resources(device_t dev)
 				(remaplimitk + 64*1024) - remapbasek);
 		}
 
-		set_top_of_ram(tolmk * 1024);
+		set_late_cbmem_top(tolmk * 1024);
 	}
 	assign_resources(dev->link_list);
 }

src/northbridge/intel/i440bx/northbridge.c

@@ -67,7 +67,7 @@ static void i440bx_domain_set_resources(device_t dev)
 		ram_resource(dev, idx++, 0, 640);
 		ram_resource(dev, idx++, 768, tolmk - 768);
 
-		set_top_of_ram(tomk * 1024);
+		set_late_cbmem_top(tomk * 1024);
 	}
 	assign_resources(dev->link_list);
 }

src/northbridge/intel/i5000/northbridge.c

@@ -107,7 +107,7 @@ static void mc_read_resources(device_t dev)
 	resource->flags = IORESOURCE_MEM | IORESOURCE_RESERVE |
 	    IORESOURCE_FIXED | IORESOURCE_STORED | IORESOURCE_ASSIGNED;
 
-	set_top_of_ram(tolm);
+	set_late_cbmem_top(tolm);
 }
 
 static struct pci_operations intel_pci_ops = {

src/northbridge/intel/i82810/northbridge.c

@@ -118,7 +118,7 @@ static void pci_domain_set_resources(device_t dev)
 	ram_resource(dev, idx++, 768, tomk - 768);
 	uma_resource(dev, idx++, uma_memory_base >> 10, uma_memory_size >> 10);
 
-	set_top_of_ram(tomk_stolen * 1024);
+	set_late_cbmem_top(tomk_stolen * 1024);
 
 	assign_resources(dev->link_list);
 }

src/northbridge/intel/i82830/northbridge.c

@@ -87,7 +87,7 @@ static void pci_domain_set_resources(device_t dev)
 
 	assign_resources(dev->link_list);
 
-	set_top_of_ram(tomk_stolen * 1024);
+	set_late_cbmem_top(tomk_stolen * 1024);
 }
 
 static struct device_operations pci_domain_ops = {

src/northbridge/intel/i855/northbridge.c

@@ -101,7 +101,7 @@ static void pci_domain_set_resources(device_t dev)
 		/* ram_resource(dev, idx++, 1024, tolmk - 1024); */
 		ram_resource(dev, idx++, 768, tolmk - 768);
 
-		set_top_of_ram(tomk * 1024);
+		set_late_cbmem_top(tomk * 1024);
 	}
 	assign_resources(dev->link_list);
 }