Hi Stefan,
On Fri, Aug 16, 2019 at 1:11 PM Stefan Roese sr@denx.de wrote:
Hi Bin,
On 15.08.19 16:19, Bin Meng wrote:
Hi Stefan,
On Thu, Aug 15, 2019 at 2:07 PM Stefan Roese sr@denx.de wrote:
Hi Simon,
On 14.08.19 21:35, Simon Glass wrote:
Hi,
On Wed, 14 Aug 2019 at 00:22, Stefan Roese sr@denx.de wrote:
Hi Simon,
(added Simon Glass and Bin to Cc)
On 13.08.19 22:16, Simon Goldschmidt wrote:
Am 25.04.2019 um 09:17 schrieb Stefan Roese: > This patch tries to implement a generic watchdog_reset() function that > can be used by all boards that want to service the watchdog device in > U-Boot. This watchdog servicing is enabled via CONFIG_WATCHDOG. > > Without this approach, new boards or platforms needed to implement a > board specific version of this functionality, mostly copy'ing the same > code over and over again into their board or platforms code base. > > With this new generic function, the scattered other functions are now > removed to be replaced by the generic one. The new version also enables > the configuration of the watchdog timeout via the DT "timeout-sec" > property (if enabled via CONFIG_OF_CONTROL). > > This patch also adds a new flag to the GD flags, to flag that the > watchdog is ready to use and adds the pointer to the watchdog device > to the GD. This enables us to remove the global "watchdog_dev" > variable, which was prone to cause problems because of its potentially > very early use in watchdog_reset(), even before the BSS is cleared. > > Signed-off-by: Stefan Roese sr@denx.de
<snip>
> --- a/include/asm-generic/global_data.h > +++ b/include/asm-generic/global_data.h > @@ -133,6 +133,9 @@ typedef struct global_data { > struct spl_handoff *spl_handoff; > # endif > #endif > +#if defined(CONFIG_WDT) > + struct udevice *watchdog_dev; > +#endif > } gd_t; > #endif > > @@ -161,5 +164,6 @@ typedef struct global_data { > #define GD_FLG_ENV_DEFAULT 0x02000 /* Default variable flag */ > #define GD_FLG_SPL_EARLY_INIT 0x04000 /* Early SPL init is done */ > #define GD_FLG_LOG_READY 0x08000 /* Log system is ready for use */ > +#define GD_FLG_WDT_READY 0x10000 /* Watchdog is ready for use */
Sorry to warm up a thread that is more than 4 months old, but I just stumbled accross this line when searching for space in 'gd':
The comment some lines above in global_data.h clearly states that the top 16 bits of flags are reserved for arch-specific flags, and your patch here uses the lowest of these 16 arch-specific flags for generic code.
I totally missed this comment.
Is this a problem? Does any arch code use the upper 16 bits? I would have thought you'd at least need to adjust the comment to reflect your new usage...
As stated above, I did not check about any other (arch-specific) GD_FLG_ definitions outside of this file.
The reason I ask is that I'd need a place to put some (~5?) 'is_initialized' bits for some code running in SPL in the 'board_init_f' code where BSS shouldn't be used. gd->flags would be ideal for that, but I'm hesistant to dive in further into the 'arch-specific' upper 16 bits...
And you should be. A quick grep shows that we already have a problem with my patch touching the upper bits:
$ git grep "define GD_FLG_" arch/x86/include/asm/global_data.h:#define GD_FLG_COLD_BOOT 0x10000 /* Cold Boot */ arch/x86/include/asm/global_data.h:#define GD_FLG_WARM_BOOT 0x20000 /* Warm Boot */
This should definitely be fixed. I see 3 options right now:
a) Reserve only the upper 8 bits for arch-specific stuff b) Use a new variable (gd->flags_arch ?) for this arch c) Remove the arch-specific GD_FLG's completely
I can't tell if c) is doable - Bin and / or Simon Glass might know, if the x86 GD_FLG_foo_BOOT are really needed in gd->flags. I see that both are assigned in the .S files, but only GD_FLG_COLD_BOOT is referenced later on:
Probably we can drop warm boot.
Bin, do you think so as well?
I believe we can drop these 2 flags completely. Currently usage of warm/cold boot flags is only limited to coreboot codes.
arch/x86/cpu/coreboot/coreboot.c::last_stage_init()
if (gd->flags & GD_FLG_COLD_BOOT) timestamp_add_to_bootstage();timestamp_add_to_bootstage() will never be called for coreboot.
Why is this the case? Will GD_FLG_COLD_BOOT never be set for the coreboot target?
GD_FLG_COLD_BOOT is only set in the 16-bit start code while on coreboot it boots directly from the 32-bit start code.
Regards, Bin