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

Hi Daniel,

On mer., sept. 26 2018, Daniel Schwierzeck daniel.schwierzeck@gmail.com wrote:

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?

Actually we support the dtb way, but the legacy kernel still neeeds this see:

https://elixir.bootlin.com/linux/v4.19-rc7/source/arch/mips/generic/board-oc...

Gregory

...

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();
  

  }

--

• Daniel