hvmloader: Allocate an 8 byte buffer to contain the VM generation id

and populate it at boot time with a value read from
"platform/generation_id". Also add code to libxl to populate this
xenstore key with the value of a new 'generation_id' parameter in the
VM config file.  Populate the ADDR package of VM_Gen_Counter ACPI
device such that the first integer evaluates to the low order 32 bits
of the buffer address and the second integer evaluates to the high
order 32 bits of the buffer address.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Committed-by: Keir Fraser <keir@xen.org>

tools/firmware/hvmloader/acpi/build.c

@@ -297,6 +297,20 @@ static int construct_secondary_tables(unsigned long *table_ptrs,
     return nr_tables;
 }
 
+unsigned long new_vm_gid(void)
+{
+    uint64_t gid;
+    unsigned char *buf;
+
+    buf = mem_alloc(8, 8);
+    if (!buf) return 0;
+
+    gid = strtoll(xenstore_read("platform/generation-id", "0"), NULL, 0);
+    *(uint64_t *)buf = gid;
+
+    return virt_to_phys(buf);    
+}
+
 void acpi_build_tables(struct acpi_config *config, unsigned int physical)
 {
     struct acpi_info *acpi_info;
@@ -309,6 +323,7 @@ void acpi_build_tables(struct acpi_config *config, unsigned int physical)
     unsigned char       *dsdt;
     unsigned long        secondary_tables[16];
     int                  nr_secondaries, i;
+    unsigned long        vm_gid_addr;
 
     /* Allocate and initialise the acpi info area. */
     mem_hole_populate_ram(ACPI_INFO_PHYSICAL_ADDRESS >> PAGE_SHIFT, 1);
@@ -421,12 +436,16 @@ void acpi_build_tables(struct acpi_config *config, unsigned int physical)
                  offsetof(struct acpi_20_rsdp, extended_checksum),
                  sizeof(struct acpi_20_rsdp));
 
+    vm_gid_addr = new_vm_gid();
+    if (!vm_gid_addr) goto oom;
+
     acpi_info->com1_present = uart_exists(0x3f8);
     acpi_info->com2_present = uart_exists(0x2f8);
     acpi_info->lpt1_present = lpt_exists(0x378);
     acpi_info->hpet_present = hpet_exists(ACPI_HPET_ADDRESS);
     acpi_info->pci_min = pci_mem_start;
     acpi_info->pci_len = pci_mem_end - pci_mem_start;
+    acpi_info->vm_gid_addr = vm_gid_addr;
 
     return;
 

tools/firmware/hvmloader/util.c

@@ -205,6 +205,78 @@ strlen(const char *s)
     return i;
 }
 
+static inline int __digit(char c, int base)
+{
+    int d = -1;
+
+    if ( (c >= '0') && (c <= '9') )
+        d = c - '0';
+
+    if ( (c >= 'A') && (c <= 'Z') )
+        d = c - 'A' + 10;
+
+    if ( (c >= 'a') && (c <= 'z') )
+        d = c - 'a' + 10;
+
+    if (d >= base)
+        d = -1;
+
+    return d;
+}
+
+long long
+strtoll(const char *s, char **end, int base)
+{
+    long long v = 0;
+    int sign = 1;
+
+    while ( (*s != '\0') && isspace(*s) )
+        s++;
+
+    if ( *s == '\0' ) goto out;
+
+    if ( *s == '-' ) {
+        sign = -1;
+        s++;
+    } else {
+        if ( *s == '+' )
+            s++;
+    }
+
+    if ( *s == '\0' ) goto out;
+
+    if ( *s == '0' ) {
+        s++;
+        if ( *s == '\0' ) goto out;
+
+        if ( *s == 'x' ) {
+            if ( base != 0 && base != 16) goto out;
+            base = 16;
+            s++;
+        } else {
+            if ( base != 0 && base != 8) goto out;
+            base = 8;
+        }
+    } else {
+        if (base != 0 && base != 10) goto out;
+        base = 10;
+    }
+
+    while ( *s != '\0' ) {
+        int d = __digit(*s, base);
+
+        if ( d < 0 ) goto out;
+
+        v = (v * base) + d;
+        s++;
+    }
+
+out:
+    if (end) *end = (char *)s;
+
+    return sign * v;
+}
+
 void *
 memset(void *s, int c, unsigned n)
 {

tools/firmware/hvmloader/util.h

@@ -152,6 +152,7 @@ int strncmp(const char *s1, const char *s2, uint32_t n);
 char *strcpy(char *dest, const char *src);
 char *strncpy(char *dest, const char *src, unsigned n);
 unsigned strlen(const char *s);
+long long strtoll(const char *s, char **end, int base);
 int memcmp(const void *s1, const void *s2, unsigned n);
 void *memcpy(void *dest, const void *src, unsigned n);
 void *memmove(void *dest, const void *src, unsigned n);