]> git.dujemihanovic.xyz Git - u-boot.git/commitdiff
efi_loader: add an EFI binary to print boot hart ID
authorHeinrich Schuchardt <heinrich.schuchardt@canonical.com>
Thu, 1 Dec 2022 18:07:57 +0000 (19:07 +0100)
committerHeinrich Schuchardt <heinrich.schuchardt@canonical.com>
Fri, 2 Dec 2022 18:17:24 +0000 (19:17 +0100)
Provide an EFI binary that prints the boot hart ID as found in the
device-tree as /chosen/boot-hartid property and as provided by the
RISCV_EFI_BOOT_PROTOCOL.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
lib/efi_loader/Makefile
lib/efi_loader/boothart.c [new file with mode: 0644]

index 8738757dd2c16b8e980e511aa578bb89ec84c065..13a35eae6c067b76eac207c996fdbb047379838d 100644 (file)
@@ -12,6 +12,8 @@ ccflags-y += -DHOST_ARCH="$(HOST_ARCH)"
 CFLAGS_efi_boottime.o += \
   -DFW_VERSION="0x$(VERSION)" \
   -DFW_PATCHLEVEL="0x$(PATCHLEVEL)"
+CFLAGS_boothart.o := $(CFLAGS_EFI) -Os -ffreestanding
+CFLAGS_REMOVE_boothart.o := $(CFLAGS_NON_EFI)
 CFLAGS_helloworld.o := $(CFLAGS_EFI) -Os -ffreestanding
 CFLAGS_REMOVE_helloworld.o := $(CFLAGS_NON_EFI)
 CFLAGS_dtbdump.o := $(CFLAGS_EFI) -Os -ffreestanding
@@ -19,6 +21,10 @@ CFLAGS_REMOVE_dtbdump.o := $(CFLAGS_NON_EFI)
 CFLAGS_initrddump.o := $(CFLAGS_EFI) -Os -ffreestanding
 CFLAGS_REMOVE_initrddump.o := $(CFLAGS_NON_EFI)
 
+ifdef CONFIG_RISCV
+always += boothart.efi
+endif
+
 ifneq ($(CONFIG_CMD_BOOTEFI_HELLO_COMPILE),)
 always += helloworld.efi
 targets += helloworld.o
diff --git a/lib/efi_loader/boothart.c b/lib/efi_loader/boothart.c
new file mode 100644 (file)
index 0000000..df176ee
--- /dev/null
@@ -0,0 +1,335 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Check RISC-V boot hart ID
+ *
+ * Copyright 2022, Heinrich Schuchardt <xypron.glpk@gmx.de>
+ *
+ * This test program reads the boot HART ID both from the device-tree from the
+ * RISCV_EFI_BOOT_PROTOCOL and writes both values to the console.
+ */
+
+#include <efi_api.h>
+#include <efi_riscv.h>
+#include <linux/libfdt.h>
+
+static const efi_guid_t riscv_efi_boot_protocol_guid =
+               RISCV_EFI_BOOT_PROTOCOL_GUID;
+static const efi_guid_t fdt_guid = EFI_FDT_GUID;
+
+static struct efi_system_table *systable;
+static struct efi_boot_services *boottime;
+static struct efi_simple_text_output_protocol *con_out;
+static const char *fdt;
+
+/**
+ * Print an unsigned 32bit value as decimal number to an u16 string
+ *
+ * @value:     value to be printed
+ * @buf:       pointer to buffer address
+ */
+static void uint2dec(u32 value, u16 *buf)
+{
+       u16 *pos = buf;
+       int i;
+       u16 c;
+       u64 f;
+
+       /*
+        * Increment by .5 and multiply with
+        * (2 << 60) / 1,000,000,000 = 0x44B82FA0.9B5A52CC
+        * to move the first digit to bit 60-63.
+        */
+       f = 0x225C17D0;
+       f += (0x9B5A52DULL * value) >> 28;
+       f += 0x44B82FA0ULL * value;
+
+       for (i = 0; i < 10; ++i) {
+               /* Write current digit */
+               c = f >> 60;
+               if (c || pos != buf)
+                       *pos++ = c + '0';
+               /* Eliminate current digit */
+               f &= 0xfffffffffffffff;
+               /* Get next digit */
+               f *= 0xaULL;
+       }
+       if (pos == buf)
+               *pos++ = '0';
+       *pos = 0;
+}
+
+/**
+ * f2h() - convert FDT value to host endianness.
+ *
+ * UEFI code is always low endian. The FDT is big endian.
+ *
+ * @val:       FDT value
+ * Return:     converted value
+ */
+static uint32_t f2h(fdt32_t val)
+{
+       char *buf = (char *)&val;
+       char i;
+
+       /* Swap the bytes */
+       i = buf[0]; buf[0] = buf[3]; buf[3] = i;
+       i = buf[1]; buf[1] = buf[2]; buf[2] = i;
+
+       return val;
+}
+
+/**
+ * memcomp() - compare two memory buffers
+ *
+ * s1:         first buffer
+ * s2:         second buffer
+ * n:          size of buffers
+ * Return:     0 if both buffers have the same content
+ */
+static int memcomp(const void *s1, const void *s2, size_t n)
+{
+       const char *pos1 = s1, *pos2 = s2;
+
+       for (size_t count = 0; count < n ; ++pos1, ++pos2, --count) {
+               if (*pos1 != *pos2)
+                       return *pos1 - *pos2;
+       }
+       return 0;
+}
+
+/**
+ * strcomp() - compare to strings
+ *
+ * @buf1:      first string
+ * @buf2:      second string
+ * Return:     0 if both strings are the same
+ */
+static int strcomp(const char *buf1, const char *buf2)
+{
+       for (; *buf1 || *buf2; ++buf1, ++buf2) {
+               if (*buf1 != *buf2)
+                       return *buf1 - *buf2;
+       }
+       return 0;
+}
+
+/**
+ * get_property() - return value of a property of an FDT node
+ *
+ * A property of the root node or one of its direct children can be
+ * retrieved.
+ *
+ * @property   name of the property
+ * @node       name of the node or NULL for root node
+ * Return:     value of the property
+ */
+static char *get_property(const char *property, const char *node)
+{
+       struct fdt_header *header = (struct fdt_header *)fdt;
+       const fdt32_t *end;
+       const fdt32_t *pos;
+       const char *strings;
+       size_t level = 0;
+       const char *nodelabel = NULL;
+
+       if (!header) {
+               con_out->output_string(con_out, u"Missing device tree\r\n");
+               return NULL;
+       }
+
+       if (f2h(header->magic) != FDT_MAGIC) {
+               con_out->output_string(con_out, u"Wrong device tree magic\r\n");
+               return NULL;
+       }
+
+       pos = (fdt32_t *)(fdt + f2h(header->off_dt_struct));
+       end = &pos[f2h(header->totalsize) >> 2];
+       strings = fdt + f2h(header->off_dt_strings);
+
+       for (; pos < end;) {
+               switch (f2h(pos[0])) {
+               case FDT_BEGIN_NODE: {
+                       const char *c = (char *)&pos[1];
+                       size_t i;
+
+                       if (level == 1)
+                               nodelabel = c;
+                       ++level;
+                       for (i = 0; c[i]; ++i)
+                               ;
+                       pos = &pos[2 + (i >> 2)];
+                       break;
+               }
+               case FDT_PROP: {
+                       struct fdt_property *prop = (struct fdt_property *)pos;
+                       const char *label = &strings[f2h(prop->nameoff)];
+                       efi_status_t ret;
+
+                       /* Check if this is the property to be returned */
+                       if (!strcomp(property, label) &&
+                           ((level == 1 && !node) ||
+                            (level == 2 && node &&
+                             !strcomp(node, nodelabel)))) {
+                               char *str;
+                               efi_uintn_t len = f2h(prop->len);
+
+                               if (!len)
+                                       return NULL;
+                               /*
+                                * The string might not be 0 terminated.
+                                * It is safer to make a copy.
+                                */
+                               ret = boottime->allocate_pool(
+                                       EFI_LOADER_DATA, len + 1,
+                                       (void **)&str);
+                               if (ret != EFI_SUCCESS) {
+                                       con_out->output_string(
+                                                   con_out,
+                                                   u"AllocatePool failed\r\n");
+                                       return NULL;
+                               }
+                               boottime->copy_mem(str, &pos[3], len);
+                               str[len] = 0;
+
+                               return str;
+                       }
+
+                       pos = &pos[3 + ((f2h(prop->len) + 3) >> 2)];
+                       break;
+               }
+               case FDT_NOP:
+                       ++pos;
+                       break;
+               case FDT_END_NODE:
+                       --level;
+                       ++pos;
+                       break;
+               case FDT_END:
+                       return NULL;
+               default:
+                       con_out->output_string(
+                               con_out, u"Invalid device tree token\r\n");
+                       return NULL;
+               }
+       }
+       con_out->output_string(
+               con_out, u"Missing FDT_END token\r\n");
+       return NULL;
+}
+
+/**
+ * get_config_table() - get configuration table
+ *
+ * @guid:      table GUID
+ * Return:     pointer to table or NULL
+ */
+static void *get_config_table(const efi_guid_t *guid)
+{
+       size_t i;
+
+       for (i = 0; i < systable->nr_tables; i++) {
+               if (!memcomp(guid, &systable->tables[i].guid, 16))
+                       return systable->tables[i].table;
+       }
+       return NULL;
+}
+
+/**
+ * fdt_get_hart() - get hart ID via RISC-V device-tree
+ *
+ * @hartid:    boot hart ID
+ * Return:     status code
+ */
+static efi_status_t fdt_get_hart(efi_uintn_t *hartid)
+{
+       char *str;
+
+       fdt = get_config_table(&fdt_guid);
+       if (!fdt) {
+               con_out->output_string(con_out, u"Missing device tree\r\n");
+               return EFI_NOT_FOUND;
+       }
+
+       str = get_property("boot-hartid", "chosen");
+       if (!str) {
+               con_out->output_string(con_out,
+                                      u"/chosen/boot-hartid missing\r\n");
+               return EFI_NOT_FOUND;
+       }
+       *hartid = f2h(*(fdt32_t *)str);
+       boottime->free_pool(str);
+
+       return EFI_SUCCESS;
+}
+
+/**
+ * prot_get_hart() - get hart ID via RISC-V Boot Protocol
+ *
+ * @hartid:    boot hart ID
+ * Return:     status code
+ */
+static efi_status_t prot_get_hart(efi_uintn_t *hartid)
+{
+       efi_status_t ret;
+       struct riscv_efi_boot_protocol *prot;
+
+       /* Get RISC-V boot protocol */
+       ret = boottime->locate_protocol(&riscv_efi_boot_protocol_guid, NULL,
+                                       (void **)&prot);
+       if (ret != EFI_SUCCESS) {
+               con_out->output_string(
+                       con_out, u"RISC-V Boot Protocol not available\r\n");
+               return ret;
+       }
+
+       /* Get boot hart ID from EFI protocol */
+       ret = prot->get_boot_hartid(prot, hartid);
+       if (ret != EFI_SUCCESS)
+               con_out->output_string(con_out,
+                                      u"Could not retrieve boot hart ID\r\n");
+       return ret;
+}
+
+/**
+ * efi_main() - entry point of the EFI application.
+ *
+ * @handle:    handle of the loaded image
+ * @systab:    system table
+ * Return:     status code
+ */
+efi_status_t EFIAPI efi_main(efi_handle_t handle,
+                            struct efi_system_table *systab)
+{
+       efi_status_t ret;
+       efi_uintn_t hartid;
+       u16 buf[16];
+
+       systable = systab;
+       boottime = systable->boottime;
+       con_out = systable->con_out;
+
+       con_out->output_string(con_out,
+                              u"\r\nBoot hart ID\r\n------------\r\n\r\n");
+
+       ret = fdt_get_hart(&hartid);
+       if (ret == EFI_SUCCESS) {
+               con_out->output_string(con_out, u"Device-tree: ");
+               uint2dec(hartid, buf);
+               con_out->output_string(con_out, buf);
+               con_out->output_string(con_out, u"\r\n");
+       }
+
+       ret = prot_get_hart(&hartid);
+       if (ret == EFI_SUCCESS) {
+               con_out->output_string(con_out, u"RISCV_EFI_BOOT_PROTOCOL: ");
+               uint2dec(hartid, buf);
+               con_out->output_string(con_out, buf);
+               con_out->output_string(con_out, u"\r\n");
+       }
+
+       con_out->output_string(con_out, u"\r\n");
+       boottime->exit(handle, EFI_SUCCESS, 0, NULL);
+
+       /* We should never arrive here */
+       return EFI_SUCCESS;
+}