Re: [U-Boot] [PATCH 5/8] x86: ifdtool: Add support for early microcode access

Hi Simon,

On Mon, Dec 15, 2014 at 8:15 AM, Simon Glass sjg@chromium.org wrote:

Some Intel CPUs use an 'FSP' binary blob which provides an inflexible means of starting up the CPU. One result is that microcode updates can only be done before RAM is available and therefore parsing of the device tree is impracticle.

Worse, the addess of the microcode update must be stored in ROM since a pointer to its start address and size is passed to the 'FSP' blob. It is not possible to perform any calculations to obtain the address and size.

To work around this, ifdtool is enhanced to work out the address and size of the first microcode update it finds in the supplied device tree. It then writes these into the correct place in the ROM. U-Boot can then start up the FSP correctly.

Signed-off-by: Simon Glass sjg@chromium.org

tools/Makefile | 1 + tools/ifdtool.c | 111 ++++++++++++++++++++++++++++++++++++++++++++++++++++---- 2 files changed, 104 insertions(+), 8 deletions(-)

diff --git a/tools/Makefile b/tools/Makefile index a4216a1..e549f8e 100644 --- a/tools/Makefile +++ b/tools/Makefile @@ -126,6 +126,7 @@ hostprogs-$(CONFIG_EXYNOS5250) += mkexynosspl hostprogs-$(CONFIG_EXYNOS5420) += mkexynosspl HOSTCFLAGS_mkexynosspl.o := -pedantic

+ifdtool-objs := $(LIBFDT_OBJS) ifdtool.o hostprogs-$(CONFIG_X86) += ifdtool

hostprogs-$(CONFIG_MX23) += mxsboot diff --git a/tools/ifdtool.c b/tools/ifdtool.c index 4077ba8..50b28d4 100644 --- a/tools/ifdtool.c +++ b/tools/ifdtool.c @@ -18,6 +18,7 @@ #include <unistd.h> #include <sys/types.h> #include <sys/stat.h> +#include <libfdt.h> #include "ifdtool.h"

#undef DEBUG @@ -34,6 +35,8 @@

enum input_file_type_t { IF_normal,

•   IF_fdt,
  

•   IF_uboot,
  

};

struct input_file { @@ -703,7 +706,7 @@ int inject_region(char *image, int size, int region_type, char *region_fname)

•                 0xffffffff so use an address relative to that. For an
  

•                 8MB ROM the start address is 0xfff80000.
  

• @write_fname: Filename to add to the image

• • @return 0 if OK, -ve on error

• • @return number of bytes written if OK, -ve on error
  */

static int write_data(char *image, int size, unsigned int addr, const char *write_fname) @@ -715,7 +718,7 @@ static int write_data(char *image, int size, unsigned int addr, if (write_fd < 0) return write_fd;

•   offset = addr + size;
  

•   offset = (uint32_t)(addr + size);
    debug("Writing %s to offset %#x\n", write_fname, offset);
  
    if (offset < 0 || offset + write_size > size) {
  

@@ -731,6 +734,69 @@ static int write_data(char *image, int size, unsigned int addr,

    close(write_fd);

•   return write_size;
  

+}

+/**

• • write_uboot() - Write U-Boot, device tree and microcode pointer
• • This writes U-Boot into a place in the flash, followed by its device tree.
• • The microcode pointer is written so that U-Boot can find the microcode in
• • the device tree very early in boot.
• • @image: Pointer to image
• • @size: Size of image in bytes

Can we remove the blank lines here?

• • @return number of bytes written if OK, -ve on error
• */

However the codes below says the return value is always 0 if OK.

+static int write_uboot(char *image, int size, struct input_file *uboot,

•                  struct input_file *fdt, unsigned int ucode_ptr)
  

+{

•   const void *blob;
  

•   const char *data;
  

•   int uboot_size;
  

•   uint32_t *ptr;
  

•   int data_size;
  

•   int offset;
  

•   int node;
  

•   int ret;
  

•   uboot_size = write_data(image, size, uboot->addr, uboot->fname);
  

•   if (uboot_size < 0)
  

•           return uboot_size;
  

•   fdt->addr = uboot->addr + uboot_size;
  

•   debug("U-Boot size %#x, FDT at %#x\n", uboot_size, fdt->addr);
  

•   ret = write_data(image, size, fdt->addr, fdt->fname);
  

•   if (ret < 0)
  

•           return ret;
  

•   if (ucode_ptr) {
  

•           blob = (void *)image + (uint32_t)(fdt->addr + size);
  

•           debug("DTB at %lx\n", (char *)blob - image);
  

•           node = fdt_node_offset_by_compatible(blob, 0,
  

•                                                "intel,microcode");
  

•           if (node < 0) {
  

•                   debug("No microcode found in FDT: %s\n",
  

•                         fdt_strerror(node));
  

•                   return -ENOENT;
  

•           }
  

•           data = fdt_getprop(blob, node, "data", &data_size);
  

•           if (!data) {
  

•                   debug("No microcode data found in FDT: %s\n",
  

•                         fdt_strerror(data_size));
  

•                   return -ENOENT;
  

•           }
  

•           offset = ucode_ptr - uboot->addr;
  

•           ptr = (void *)image + offset;
  

•           ptr[0] = fdt->addr + (data - image);
  

This is the bug that causes Crown Bay fails to boot. It should be:

ptr[0] = uboot->addr + (data - image);

•           ptr[1] = data_size;
  

•           debug("Wrote microcode pointer at %x: addr=%x, size=%x\n",
  

•                 ucode_ptr, ptr[0], ptr[1]);
  

•   }
  

•   return 0;
  

}

@@ -800,7 +866,7 @@ int main(int argc, char *argv[]) char *desc_fname = NULL, *addr_str = NULL; int region_type = -1, inputfreq = 0; enum spi_frequency spifreq = SPI_FREQUENCY_20MHZ;

•   struct input_file input_file[WRITE_MAX], *ifile;
  

•   struct input_file input_file[WRITE_MAX], *ifile, *fdt = NULL;
    unsigned char wr_idx, wr_num = 0;
    int rom_size = -1;
    bool write_it;
  

@@ -808,6 +874,8 @@ int main(int argc, char *argv[]) char *outfile = NULL; struct stat buf; int size = 0;

•   unsigned int ucode_ptr = 0;
  

•   bool have_uboot = false;
    int bios_fd;
    char *image;
    int ret;
  

@@ -817,18 +885,21 @@ int main(int argc, char *argv[]) {"descriptor", 1, NULL, 'D'}, {"em100", 0, NULL, 'e'}, {"extract", 0, NULL, 'x'},

•           {"fdt", 1, NULL, 'f'},
            {"inject", 1, NULL, 'i'},
            {"lock", 0, NULL, 'l'},
  

•           {"microcode", 1, NULL, 'm'},
            {"romsize", 1, NULL, 'r'},
            {"spifreq", 1, NULL, 's'},
            {"unlock", 0, NULL, 'u'},
  

•           {"uboot", 1, NULL, 'U'},
            {"write", 1, NULL, 'w'},
            {"version", 0, NULL, 'v'},
            {"help", 0, NULL, 'h'},
            {0, 0, 0, 0}
    };
  
  

•   while ((opt = getopt_long(argc, argv, "cdD:ehi:lr:s:uvw:x?",
  

•   while ((opt = getopt_long(argc, argv, "cdD:ef:hi:lm:r:s:uU:vw:x?",
                              long_options, &option_index)) != EOF) {
            switch (opt) {
            case 'c':
  

@@ -871,6 +942,9 @@ int main(int argc, char *argv[]) case 'l': mode_locked = 1; break;

•           case 'm':
  

•                   ucode_ptr = strtoul(optarg, NULL, 0);
  

•                   break;
            case 'r':
                    rom_size = strtol(optarg, NULL, 0);
                    debug("ROM size %d\n", rom_size);
  

@@ -904,6 +978,8 @@ int main(int argc, char *argv[]) exit(EXIT_SUCCESS); break; case 'w':

•           case 'U':
  

•           case 'f':
                    ifile = &input_file[wr_num];
                    mode_write = 1;
                    if (wr_num < WRITE_MAX) {
  

@@ -913,7 +989,12 @@ int main(int argc, char *argv[]) exit(EXIT_FAILURE); } ifile->addr = strtol(optarg, NULL, 0);

•                           ifile->type = IF_normal;
  

•                           ifile->type = opt == 'f' ? IF_fdt :
  

•                                   opt == 'U' ? IF_uboot : IF_normal;
  

•                           if (ifile->type == IF_fdt)
  

•                                   fdt = ifile;
  

•                           else if (ifile->type == IF_uboot)
  

•                                   have_uboot = true;
                            wr_num++;
                    } else {
                            fprintf(stderr,
  

@@ -970,6 +1051,13 @@ int main(int argc, char *argv[]) exit(EXIT_FAILURE); }

•   if (have_uboot && !fdt) {
  

•           fprintf(stderr,
  

•                   "You must supply a device tree file for U-Boot\n\n");
  

•           print_usage(argv[0]);
  

•           exit(EXIT_FAILURE);
  

•   }
  

•   filename = argv[optind];
    if (optind + 2 != argc)
            outfile = argv[optind + 1];
  

@@ -1034,9 +1122,16 @@ int main(int argc, char *argv[]) if (mode_write) { for (wr_idx = 0; wr_idx < wr_num; wr_idx++) { ifile = &input_file[wr_idx];

•                   ret = write_data(image, size, ifile->addr,
  

•                   if (ifile->type == IF_fdt) {
  

•                           continue;
  

•                   } else if (ifile->type == IF_uboot) {
  

•                           ret = write_uboot(image, size, ifile, fdt,
  

•                                             ucode_ptr);
  

•                   } else {
  

•                           ret = write_data(image, size, ifile->addr,
                                     ifile->fname);
  

•                   if (ret)
  

•                   }
  

•                   if (ret < 0)
                            break;
            }
    }
  

@@ -1071,5 +1166,5 @@ int main(int argc, char *argv[]) free(image); close(bios_fd);

•   return ret ? 1 : 0;
  

•   return ret < 0 ? 1 : 0;
  

}

Regards, Bin