From: Julien Grall <julien.grall@arm.com>
Date: Fri, 20 May 2022 12:09:26 +0000 (+0100)
Subject: xen/arm: mm: Re-implement early_fdt_map() using map_pages_to_xen()
X-Git-Tag: archive/raspbian/4.17.0-1+rpi1^2~33^2~597
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=f8c818848fa64b1957411faea7cee22d677cebcc;p=xen.git

xen/arm: mm: Re-implement early_fdt_map() using map_pages_to_xen()

Now that map_pages_to_xen() has been extended to support 2MB mappings,
we can replace the create_mappings() calls by map_pages_to_xen() calls.

The mapping can also be marked read-only as Xen should not modify
the host Device Tree during boot.

Signed-off-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Hongda Deng <Hongda.Heng@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
---

diff --git a/xen/arch/arm/mm.c b/xen/arch/arm/mm.c
index 64a79d45b3..03f970e4d1 100644
--- a/xen/arch/arm/mm.c
+++ b/xen/arch/arm/mm.c
@@ -574,6 +574,7 @@ void * __init early_fdt_map(paddr_t fdt_paddr)
     paddr_t offset;
     void *fdt_virt;
     uint32_t size;
+    int rc;
 
     /*
      * Check whether the physical FDT address is set and meets the minimum
@@ -589,8 +590,12 @@ void * __init early_fdt_map(paddr_t fdt_paddr)
     /* The FDT is mapped using 2MB superpage */
     BUILD_BUG_ON(BOOT_FDT_VIRT_START % SZ_2M);
 
-    create_mappings(xen_second, BOOT_FDT_VIRT_START, paddr_to_pfn(base_paddr),
-                    SZ_2M >> PAGE_SHIFT, SZ_2M);
+    rc = map_pages_to_xen(BOOT_FDT_VIRT_START, maddr_to_mfn(base_paddr),
+                          SZ_2M >> PAGE_SHIFT,
+                          PAGE_HYPERVISOR_RO | _PAGE_BLOCK);
+    if ( rc )
+        panic("Unable to map the device-tree.\n");
+
 
     offset = fdt_paddr % SECOND_SIZE;
     fdt_virt = (void *)BOOT_FDT_VIRT_START + offset;
@@ -604,9 +609,12 @@ void * __init early_fdt_map(paddr_t fdt_paddr)
 
     if ( (offset + size) > SZ_2M )
     {
-        create_mappings(xen_second, BOOT_FDT_VIRT_START + SZ_2M,
-                        paddr_to_pfn(base_paddr + SZ_2M),
-                        SZ_2M >> PAGE_SHIFT, SZ_2M);
+        rc = map_pages_to_xen(BOOT_FDT_VIRT_START + SZ_2M,
+                              maddr_to_mfn(base_paddr + SZ_2M),
+                              SZ_2M >> PAGE_SHIFT,
+                              PAGE_HYPERVISOR_RO | _PAGE_BLOCK);
+        if ( rc )
+            panic("Unable to map the device-tree\n");
     }
 
     return fdt_virt;