Hi Simon,
On Tue, Jul 12, 2016 at 03:56:01PM -0600, Simon Glass wrote:
On 8 July 2016 at 09:41, Max Filippov jcmvbkbc@gmail.com wrote:
From: Chris Zankel chris@zankel.net
The Xtensa processor architecture is a configurable, extensible, and synthesizable 32-bit RISC processor core provided by Cadence.
This is the first part of the basic architecture port with changes to common files. The 'arch/xtensa' directory, and boards and additional drivers will be in separate commits.
Signed-off-by: Chris Zankel chris@zankel.net Signed-off-by: Max Filippov jcmvbkbc@gmail.com
MAINTAINERS | 5 +++ MAKEALL | 6 +++ Makefile | 10 ++++- cmd/bdinfo.c | 22 ++++++++++ common/board_f.c | 7 ++-- common/image.c | 1 + doc/README.xtensa | 100 ++++++++++++++++++++++++++++++++++++++++++++ examples/standalone/stubs.c | 47 +++++++++++++++++++++ include/image.h | 1 + include/linux/stat.h | 4 +- 10 files changed, 197 insertions(+), 6 deletions(-) create mode 100644 doc/README.xtensa
Reviewed-by: Simon Glass sjg@chromium.org
Thanks for the review.
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diff --git a/MAKEALL b/MAKEALL index 7e42f10..e669aa9 100755 --- a/MAKEALL +++ b/MAKEALL
This is deprecated and will be removed soon, so you don't need to update it. See buildman.
Ok.
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diff --git a/cmd/bdinfo.c b/cmd/bdinfo.c index 1c4bed9..076b950 100644 --- a/cmd/bdinfo.c +++ b/cmd/bdinfo.c @@ -563,6 +563,28 @@ int do_bdinfo(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) return 0; }
+#elif defined(CONFIG_XTENSA)
+int do_bdinfo(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) +{
bd_t *bd = gd->bd;print_num("boot_params", (ulong)bd->bi_boot_params);print_num("memstart", (ulong)bd->bi_memstart);print_lnum("memsize", (u64)bd->bi_memsize);print_num("flashstart", (ulong)bd->bi_flashstart);print_num("flashsize", (ulong)bd->bi_flashsize);print_num("flashoffset", (ulong)bd->bi_flashoffset);+#if defined(CONFIG_CMD_NET)
print_eth(0);printf("ip_addr = %s\n", getenv("ipaddr"));+#endif
printf("baudrate = %d bps\n", gd->baudrate);It would be great if you could put this in a common function so that other archs can call it. There is a lot of duplication in this file.
Ok, let me look at that.
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diff --git a/doc/README.xtensa b/doc/README.xtensa new file mode 100644 index 0000000..a461714 --- /dev/null +++ b/doc/README.xtensa
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+The header files for one particular processor configuration are inside +a variant specific directory located in the arch/xtensa/include/asm
variant-specific
Ok.
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+Windowed ABI presents unique difficulties with the approach based on +keeping global data pointer in dedicated register. Because the register +window rotates during a call, there is no register that is constantly +available for the gd pointer. Therefore, a global variable is used in +the same manner as i386.
Or you could make gd a simple global variable. It you keep it in the data section that should work.
gd is a simple global variable on xtensa, I haven't actually checked what 'in the same manner as i386' means now. Will fix wording.
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+U-Boot for Xtensa provides a special memory exception handler to prevent +hanging. The memory exception handler simply skips over the offending +instruction. It is called for all memory exception causes that might +be triggered by bad user input. While this is simplistic, it's better +than hanging in most cases, while keeping U-Boot small and simple.
Wouldn't it be better to print an exception message? See for example ARM's do_prefetch_abort().
I see that on ARM such errors result in panic and reset. Sure I can do that if that's the preferred way of dealing with such errors.