Kexec for MIPS currently does not support loading devicetrees, unless
they are embedded in the kernel elf file.
Add an option to either pass a new dtb file or - if not specified - to
be generated from existing device tree on the device. As new generic
platforms require a dtb to be passed separately this is required for
such platforms and will be ignored by the kernel otherwise.
Generic kexec infrastructure for dtb support is used.
Signed-off-by: Marcin Nowakowski <marcin.nowakowski@xxxxxxxxxx>
Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Cc: linux-mips@xxxxxxxxxxxxxx
---
kexec/arch/mips/Makefile | 13 +++++++++++++
kexec/arch/mips/crashdump-mips.c | 3 +++
kexec/arch/mips/include/arch/options.h | 5 ++++-
kexec/arch/mips/kexec-elf-mips.c | 34 +++++++++++++++++++++++++++++++---
kexec/arch/mips/kexec-mips.c | 8 ++++++++
kexec/arch/mips/kexec-mips.h | 9 +++++++++
6 files changed, 68 insertions(+), 4 deletions(-)
diff --git a/kexec/arch/mips/Makefile b/kexec/arch/mips/Makefile
index 03bdb9a..1fe7886 100644
--- a/kexec/arch/mips/Makefile
+++ b/kexec/arch/mips/Makefile
@@ -6,6 +6,19 @@ mips_KEXEC_SRCS += kexec/arch/mips/kexec-elf-mips.c
mips_KEXEC_SRCS += kexec/arch/mips/kexec-elf-rel-mips.c
mips_KEXEC_SRCS += kexec/arch/mips/crashdump-mips.c
+mips_FS2DT = kexec/fs2dt.c
+mips_FS2DT_INCLUDE = \
+ -include $(srcdir)/kexec/arch/mips/crashdump-mips.h \
+ -include $(srcdir)/kexec/arch/mips/kexec-mips.h
+
+mips_DT_OPS += kexec/dt-ops.c
+
+include $(srcdir)/kexec/libfdt/Makefile.libfdt
+
+libfdt_SRCS += $(LIBFDT_SRCS:%=kexec/libfdt/%)
+mips_CPPFLAGS += -I$(srcdir)/kexec/libfdt
+mips_KEXEC_SRCS += $(libfdt_SRCS)
+
mips_ADD_BUFFER =
mips_ADD_SEGMENT =
mips_VIRT_TO_PHYS =
diff --git a/kexec/arch/mips/crashdump-mips.c b/kexec/arch/mips/crashdump-mips.c
index 278ee01..d6cff5a 100644
--- a/kexec/arch/mips/crashdump-mips.c
+++ b/kexec/arch/mips/crashdump-mips.c
@@ -39,6 +39,9 @@
* A separate program header is created for backup region */
static struct memory_range crash_memory_range[CRASH_MAX_MEMORY_RANGES];
+/* Not used currently but required by generic fs2dt code */
+struct memory_ranges usablemem_rgns;
+
/* Memory region reserved for storing panic kernel and other data. */
static struct memory_range crash_reserved_mem;
diff --git a/kexec/arch/mips/include/arch/options.h b/kexec/arch/mips/include/arch/options.h
index a18251b..86b620f 100644
--- a/kexec/arch/mips/include/arch/options.h
+++ b/kexec/arch/mips/include/arch/options.h
@@ -3,6 +3,7 @@
#define OPT_ARCH_MAX (OPT_MAX+0)
#define OPT_APPEND (OPT_ARCH_MAX+0)
+#define OPT_DTB (OPT_ARCH_MAX+1)
/* Options relevant to the architecture (excluding loader-specific ones),
* in this case none:
@@ -10,7 +11,9 @@
#define KEXEC_ARCH_OPTIONS \
KEXEC_OPTIONS \
{"command-line", 1, 0, OPT_APPEND}, \
- {"append", 1, 0, OPT_APPEND},
+ {"append", 1, 0, OPT_APPEND}, \
+ {"dtb", 1, 0, OPT_DTB },
+
#define KEXEC_ARCH_OPT_STR KEXEC_OPT_STR ""
diff --git a/kexec/arch/mips/kexec-elf-mips.c b/kexec/arch/mips/kexec-elf-mips.c
index 7cb06f1..6ca7ca0 100644
--- a/kexec/arch/mips/kexec-elf-mips.c
+++ b/kexec/arch/mips/kexec-elf-mips.c
@@ -29,13 +29,16 @@
#include "kexec-mips.h"
#include "crashdump-mips.h"
#include <arch/options.h>
+#include "../../fs2dt.h"
+#include "../../dt-ops.h"
static const int probe_debug = 0;
#define BOOTLOADER "kexec"
-#define MAX_COMMAND_LINE 256
#define UPSZ(X) _ALIGN_UP(sizeof(X), 4)
-static char cmdline_buf[256] = "kexec ";
+
+#define CMDLINE_PREFIX "kexec "
+static char cmdline_buf[COMMAND_LINE_SIZE] = CMDLINE_PREFIX;
int elf_mips_probe(const char *buf, off_t len)
{
@@ -74,6 +77,10 @@ int elf_mips_load(int argc, char **argv, const char *buf, off_t len,
int result;
unsigned long cmdline_addr;
size_t i;
+ off_t dtb_length;
+ char *dtb_buf;
+ unsigned long long kernel_addr = 0, kernel_size = 0;
+ unsigned long pagesize = getpagesize();
/* Need to append some command line parameters internally in case of
* taking crash dumps.
@@ -92,8 +99,11 @@ int elf_mips_load(int argc, char **argv, const char *buf, off_t len,
for (i = 0; i < ehdr.e_phnum; i++) {
struct mem_phdr *phdr;
phdr = &ehdr.e_phdr[i];
- if (phdr->p_type == PT_LOAD)
+ if (phdr->p_type == PT_LOAD) {
phdr->p_paddr = virt_to_phys(phdr->p_paddr);
+ kernel_addr = phdr->p_paddr;
+ kernel_size = phdr->p_memsz;
+ }
}
/* Load the Elf data */
@@ -130,10 +140,28 @@ int elf_mips_load(int argc, char **argv, const char *buf, off_t len,
else
cmdline_addr = 0;
+ /* MIPS systems that have been converted to use device tree
+ * passed through UHI will use commandline in the DTB and
+ * the DTB passed as a separate buffer. Note that
+ * CMDLINE_PREFIX is skipped here intentionally, as it is
+ * used only in the legacy method */
+
+ if (arch_options.dtb_file) {
+ dtb_buf = slurp_file(arch_options.dtb_file, &dtb_length);
+ } else {
+ create_flatten_tree(&dtb_buf, &dtb_length, cmdline_buf + strlen(CMDLINE_PREFIX));
+ }
+
+ /* This is a legacy method for commandline passing used
+ * currently by Octeon CPUs only */
add_buffer(info, cmdline_buf, sizeof(cmdline_buf),
sizeof(cmdline_buf), sizeof(void *),
cmdline_addr, 0x0fffffff, 1);
+ add_buffer(info, dtb_buf, dtb_length, dtb_length, 0,
+ _ALIGN_UP(kernel_addr + kernel_size, pagesize),
+ 0x0fffffff, 1);
+
return 0;
}
diff --git a/kexec/arch/mips/kexec-mips.c b/kexec/arch/mips/kexec-mips.c
index 867e9c3..2605c17 100644
--- a/kexec/arch/mips/kexec-mips.c
+++ b/kexec/arch/mips/kexec-mips.c
@@ -21,6 +21,10 @@
#include "kexec-mips.h"
#include <arch/options.h>
+/* Currently not used but required by top-level fs2dt code */
+off_t initrd_base = 0;
+off_t initrd_size = 0;
+
static struct memory_range memory_range[MAX_MEMORY_RANGES];
/* Return a sorted list of memory ranges. */
@@ -77,6 +81,7 @@ void arch_usage(void)
printf(
" --command-line=STRING Set the kernel command line to STRING.\n"
" --append=STRING Set the kernel command line to STRING.\n"
+ " --dtb=FILE Use FILE as the device tree blob.\n"
);
}
@@ -103,6 +108,9 @@ int arch_process_options(int argc, char **argv)
case OPT_APPEND:
arch_options.command_line = optarg;
break;
+ case OPT_DTB:
+ arch_options.dtb_file = optarg;
+ break;
default:
break;
}
diff --git a/kexec/arch/mips/kexec-mips.h b/kexec/arch/mips/kexec-mips.h
index 2991b2d..a609fb5 100644
--- a/kexec/arch/mips/kexec-mips.h
+++ b/kexec/arch/mips/kexec-mips.h
@@ -1,6 +1,11 @@
#ifndef KEXEC_MIPS_H
#define KEXEC_MIPS_H
+#include <sys/types.h>
+
+#define BOOT_BLOCK_VERSION 17
+#define BOOT_BLOCK_LAST_COMP_VERSION 16
+
#define MAX_MEMORY_RANGES 64
#define MAX_LINE 160
@@ -14,7 +19,11 @@ void elf_mips_usage(void);
struct arch_options_t {
char *command_line;
+ char *dtb_file;
int core_header_type;
};
+extern struct memory_ranges usablemem_rgns;
+extern off_t initrd_base, initrd_size;
+
#endif /* KEXEC_MIPS_H */
--
2.7.4
