[PATCH v3 54/62] arm/acpi: Create min DT stub for Dom0

shannon.zhao at linaro.org shannon.zhao at linaro.org
Tue Nov 17 01:40:53 PST 2015


From: Shannon Zhao <shannon.zhao at linaro.org>

Create a DT for Dom0 for ACPI-case only. DT contains minimal required
informations such as Dom0 bootargs, initrd, efi description table and
address of uefi memory table.

Signed-off-by: Naresh Bhat <naresh.bhat at linaro.org>
Signed-off-by: Parth Dixit <parth.dixit at linaro.org>
Signed-off-by: Shannon Zhao <shannon.zhao at linaro.org>
---
 xen/arch/arm/domain_build.c | 142 ++++++++++++++++++++++++++++++++++++++++++++
 xen/common/efi/boot.c       |  47 +++++++++++++++
 xen/include/asm-arm/setup.h |   2 +
 3 files changed, 191 insertions(+)

diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
index 55f85b4..6d8536b 100644
--- a/xen/arch/arm/domain_build.c
+++ b/xen/arch/arm/domain_build.c
@@ -1358,6 +1358,144 @@ static int prepare_dtb(struct domain *d, struct kernel_info *kinfo)
 
 #ifdef CONFIG_ACPI
 #define XEN_HYPERVISOR_ID 0x000058656E564D4D  /* "XenVMM" */
+#define ACPI_DOM0_FDT_MIN_SIZE 4096
+
+static int make_chosen_node(const struct kernel_info *kinfo,
+                            struct membank tbl_add[])
+{
+    int res;
+    const char *bootargs = NULL;
+    const struct bootmodule *mod = kinfo->kernel_bootmodule;
+    void *fdt = kinfo->fdt;
+
+    DPRINT("Create chosen node\n");
+    res = fdt_begin_node(fdt, "chosen");
+    if ( res )
+        return res;
+
+    if ( mod && mod->cmdline[0] )
+    {
+        bootargs = &mod->cmdline[0];
+        res = fdt_property(fdt, "bootargs", bootargs, strlen(bootargs) + 1);
+        if ( res )
+           return res;
+    }
+
+    /*
+     * If the bootloader provides an initrd, we must create a placeholder
+     * for the initrd properties. The values will be replaced later.
+     */
+    if ( mod && mod->size )
+    {
+        u64 a = 0;
+        res = fdt_property(kinfo->fdt, "linux,initrd-start", &a, sizeof(a));
+        if ( res )
+            return res;
+
+        res = fdt_property(kinfo->fdt, "linux,initrd-end", &a, sizeof(a));
+        if ( res )
+            return res;
+    }
+
+    res = fdt_end_node(fdt);
+
+    return res;
+}
+
+static int acpi_make_hypervisor_node(const struct kernel_info *kinfo,
+                                     struct membank tbl_add[])
+{
+    const char compat[] =
+        "xen,xen-"__stringify(XEN_VERSION)"."__stringify(XEN_SUBVERSION)"\0"
+        "xen,xen";
+    int res;
+    /* Convenience alias */
+    void *fdt = kinfo->fdt;
+
+    DPRINT("Create hypervisor node\n");
+
+    /* See linux Documentation/devicetree/bindings/arm/xen.txt */
+    res = fdt_begin_node(fdt, "hypervisor");
+    if ( res )
+        return res;
+
+    /* Cannot use fdt_property_string due to embedded nulls */
+    res = fdt_property(fdt, "compatible", compat, sizeof(compat));
+    if ( res )
+        return res;
+
+    res = arm_acpi_make_efi_nodes(fdt, tbl_add);
+    if ( res )
+        return res;
+
+    res = fdt_end_node(fdt);
+
+    return res;
+}
+
+/*
+ * Prepare a minimal DTB for Dom0 which contains bootargs, initrd, memory
+ * information, EFI table.
+ */
+static int create_acpi_dtb(struct kernel_info *kinfo, struct membank tbl_add[])
+{
+    int new_size;
+    int ret;
+
+    DPRINT("Prepare a min DTB for DOM0\n");
+
+    /* Allocate min size for DT */
+    new_size = ACPI_DOM0_FDT_MIN_SIZE;
+    kinfo->fdt = xmalloc_bytes(new_size);
+
+    if ( kinfo->fdt == NULL )
+        return -ENOMEM;
+
+    /* Create a new empty DT for DOM0 */
+    ret = fdt_create(kinfo->fdt, new_size);
+    if ( ret < 0 )
+        goto err;
+
+    ret = fdt_finish_reservemap(kinfo->fdt);
+    if ( ret < 0 )
+        goto err;
+
+    ret = fdt_begin_node(kinfo->fdt, "/");
+    if ( ret < 0 )
+        goto err;
+
+    ret = fdt_property_cell(kinfo->fdt, "#address-cells", 2);
+    if ( ret )
+        return ret;
+
+    ret = fdt_property_cell(kinfo->fdt, "#size-cells", 1);
+    if ( ret )
+        return ret;
+
+    /* Create a chosen node for DOM0 */
+    ret = make_chosen_node(kinfo, tbl_add);
+    if ( ret )
+        goto err;
+
+    ret = acpi_make_hypervisor_node(kinfo, tbl_add);
+    if ( ret )
+        goto err;
+
+    ret = fdt_end_node(kinfo->fdt);
+    if ( ret < 0 )
+        goto err;
+
+    ret = fdt_finish(kinfo->fdt);
+    if ( ret < 0 )
+        goto err;
+
+    return 0;
+
+  err:
+    printk("Device tree generation failed (%d).\n", ret);
+    xfree(kinfo->fdt);
+    return -EINVAL;
+}
 
 static void acpi_map_rest_tables(struct domain *d)
 {
@@ -1755,6 +1893,10 @@ static int prepare_acpi(struct domain *d, struct kernel_info *kinfo)
         return rc;
     }
 
+    rc = create_acpi_dtb(kinfo, tbl_add);
+    if ( rc != 0 )
+        return rc;
+
     return 0;
 }
 #else
diff --git a/xen/common/efi/boot.c b/xen/common/efi/boot.c
index ff2faed..d233cef 100644
--- a/xen/common/efi/boot.c
+++ b/xen/common/efi/boot.c
@@ -1304,6 +1304,53 @@ void __init acpi_create_efi_mmap_table(paddr_t paddr, void *efi_acpi_table,
         memory_map[offset].Attribute = EFI_MEMORY_WB;
     }
 }
+
+/* Create place holder for efi values. */
+int __init arm_acpi_make_efi_nodes(void *fdt, struct membank tbl_add[])
+{
+    u64 fdt_val64;
+    u32 fdt_val32;
+    int desc_ver = mdesc_ver;
+    int res;
+
+    res = fdt_begin_node(fdt, "uefi");
+    if ( res )
+        return res;
+
+    fdt_val64 = cpu_to_fdt64(tbl_add[TBL_EFIT].start);
+    res = fdt_property(fdt, "xen,uefi-system-table",
+                       &fdt_val64, sizeof(fdt_val64));
+    if ( res )
+        return res;
+
+    fdt_val64 = cpu_to_fdt64(tbl_add[TBL_MMAP].start);
+    res = fdt_property(fdt, "xen,uefi-mmap-start",
+                       &fdt_val64,  sizeof(fdt_val64));
+    if ( res )
+        return res;
+
+    fdt_val32 = cpu_to_fdt32(tbl_add[TBL_MMAP].size);
+    res = fdt_property(fdt, "xen,uefi-mmap-size",
+                       &fdt_val32,  sizeof(fdt_val32));
+    if ( res )
+        return res;
+
+    fdt_val32 = cpu_to_fdt32(sizeof(EFI_MEMORY_DESCRIPTOR));
+    res = fdt_property(fdt, "xen,uefi-mmap-desc-size",
+                         &fdt_val32, sizeof(fdt_val32));
+    if ( res )
+        return res;
+
+    fdt_val32 = cpu_to_fdt32(desc_ver);
+    res = fdt_property(fdt, "xen,uefi-mmap-desc-ver",
+                         &fdt_val32, sizeof(fdt_val32));
+    if ( res )
+        return res;
+
+    res = fdt_end_node(fdt);
+
+    return res;
+}
 #endif
 
 #ifndef CONFIG_ARM /* TODO - runtime service support */
diff --git a/xen/include/asm-arm/setup.h b/xen/include/asm-arm/setup.h
index 35447ee..c4cf5ea 100644
--- a/xen/include/asm-arm/setup.h
+++ b/xen/include/asm-arm/setup.h
@@ -60,6 +60,8 @@ void acpi_create_efi_mmap_table(paddr_t paddr, void *efi_acpi_table,
                                 const struct meminfo *mem,
                                 struct membank tbl_add[]);
 
+int arm_acpi_make_efi_nodes(void *fdt, struct membank tbl_add[]);
+
 int construct_dom0(struct domain *d);
 
 void discard_initial_modules(void);
-- 
2.1.0




More information about the linux-arm-kernel mailing list