Re: [U-Boot] [PATCH 6/6] MIPS: bootm: Add support for Vcore III linux kernel

On 25.09.2018 15:01, Gregory CLEMENT wrote:

The kernels built for the Vcore III linux kernel have different expectation in the way the data were passed.

Unlike with yamon, the command line is expected to be a single string passed in argv[1]. An other expectation is that the arguments are located in the cached address space.

However, like yamon, they expect that rd_start and rd_size was passed by the bootloader in the command line of the kernel, and besides that it also wait for the root=/dev/ram0.

Can't you use existing boot interfaces? The preferred way would be to pass a device-tree blob to the kernel and let U-Boot fill the bootargs in that DTB. I wonder why the linux-mips guys let you add another boot interface. Or do you simply want to boot some legacy or propietary kernels?

Signed-off-by: Gregory CLEMENT gregory.clement@bootlin.com

arch/mips/lib/bootm.c | 62 +++++++++++++++++++++++++++++-------------- 1 file changed, 42 insertions(+), 20 deletions(-)

diff --git a/arch/mips/lib/bootm.c b/arch/mips/lib/bootm.c index deca5189e3..417f5ce452 100644 --- a/arch/mips/lib/bootm.c +++ b/arch/mips/lib/bootm.c @@ -44,22 +44,38 @@ void arch_lmb_reserve(struct lmb *lmb) lmb_reserve(lmb, sp, gd->ram_top - sp); }

-static void linux_cmdline_init(void) +static void linux_cmdline_init(int vcoreiii) {

• if (!vcoreiii) {

• linux_argv = (char **)UNCACHED_SDRAM(gd->bd->bi_boot_params);
  

• linux_argp = (char *)(linux_argv + LINUX_MAX_ARGS);
  

• } else {

• /*
  

•  * Vcore III linux kernels expect arguments in the cached
  

•  * address space. They also expect the command line being a
  

•  * single string in the first argument
  

•  */
  

• linux_argv = (char **)(gd->bd->bi_boot_params);
  

• linux_argp = (char *)(linux_argv + LINUX_MAX_ARGS);
  

• linux_argv[1] = linux_argp;
  

• } linux_argc = 1;

• linux_argv = (char **)UNCACHED_SDRAM(gd->bd->bi_boot_params); linux_argv[0] = 0;
• linux_argp = (char *)(linux_argv + LINUX_MAX_ARGS);

}

-static void linux_cmdline_set(const char *value, size_t len) +static void linux_cmdline_set(const char *value, size_t len, int vcoreiii) {

• linux_argv[linux_argc] = linux_argp; memcpy(linux_argp, value, len);
• linux_argp[len] = 0;

• if (!vcoreiii) {

• linux_argv[linux_argc] = linux_argp;
  

• linux_argp[len] = 0;
  

• linux_argc++;
  

• } else {

• linux_argp[len] = ' ';
  

• linux_argp[len + 1] = 0;
  

• linux_argc = 2;
  

• } linux_argp += len + 1;

• linux_argc++;

}

static void linux_cmdline_dump(void) @@ -73,12 +89,10 @@ static void linux_cmdline_dump(void) debug(" arg %03d: %s\n", i, linux_argv[i]); }

-static void linux_cmdline_legacy(bootm_headers_t *images) +static void linux_cmdline_legacy(bootm_headers_t *images, int vcoreiii) { const char *bootargs, *next, *quote;

• linux_cmdline_init();

• linux_cmdline_init(vcoreiii); bootargs = env_get("bootargs"); if (!bootargs) return;

@@ -104,7 +118,7 @@ static void linux_cmdline_legacy(bootm_headers_t *images) if (!next) next = bootargs + strlen(bootargs);

• linux_cmdline_set(bootargs, next - bootargs);
  

• linux_cmdline_set(bootargs, next - bootargs, vcoreiii);
  
  

  if (*next) next++;

@@ -113,7 +127,7 @@ static void linux_cmdline_legacy(bootm_headers_t *images) } }

-static void linux_cmdline_append(bootm_headers_t *images) +static void linux_cmdline_append(bootm_headers_t *images, int vcoreiii) { char buf[24]; ulong mem, rd_start, rd_size; @@ -121,7 +135,7 @@ static void linux_cmdline_append(bootm_headers_t *images) /* append mem */ mem = gd->ram_size >> 20; sprintf(buf, "mem=%luM", mem);

• linux_cmdline_set(buf, strlen(buf));

• linux_cmdline_set(buf, strlen(buf), vcoreiii);

  /* append rd_start and rd_size */ rd_start = images->initrd_start;

@@ -129,9 +143,13 @@ static void linux_cmdline_append(bootm_headers_t *images)

if (rd_size) { sprintf(buf, "rd_start=0x%08lX", rd_start);

• linux_cmdline_set(buf, strlen(buf));
  

• linux_cmdline_set(buf, strlen(buf), vcoreiii);
  

  sprintf(buf, "rd_size=0x%lX", rd_size);

• linux_cmdline_set(buf, strlen(buf));
  

• linux_cmdline_set(buf, strlen(buf), vcoreiii);
  

• if (vcoreiii) {
  

• 	sprintf(buf, "root=/dev/ram0");
  

• 	linux_cmdline_set(buf, strlen(buf), vcoreiii);
  

• }
  

  }

}

@@ -276,11 +294,15 @@ static void boot_prep_linux(bootm_headers_t *images) boot_reloc_fdt(images); boot_setup_fdt(images); } else {

• if (CONFIG_IS_ENABLED(MIPS_BOOT_CMDLINE_LEGACY)) {
  

• 	linux_cmdline_legacy(images);
  

• if (CONFIG_IS_ENABLED(SOC_VCOREIII)) {
  

• 	linux_cmdline_legacy(images, 1);
  

• 	linux_cmdline_append(images, 1);
  

• 	linux_cmdline_dump();
  

• } else if (CONFIG_IS_ENABLED(MIPS_BOOT_CMDLINE_LEGACY)) {
  

• 	linux_cmdline_legacy(images, 0);
  
  if (!CONFIG_IS_ENABLED(MIPS_BOOT_ENV_LEGACY))
  

• 		linux_cmdline_append(images);
  

• 		linux_cmdline_append(images, 0);
  
  linux_cmdline_dump();
  

  }