> -----Original Message----- > From: Hilman, Kevin > Sent: Saturday, December 10, 2011 6:51 AM > To: Tony Lindgren > Cc: Ilya Yanok; linux-omap@xxxxxxxxxxxxxxx; wd@xxxxxxx; dzu@xxxxxxx; > sasha_d@xxxxxxxxxxx; Hiremath, Vaibhav > Subject: Re: [PATCH] AM35xx: disable checking for reserved feature bits > > Tony Lindgren <tony@xxxxxxxxxxx> writes: > > [...] > > >> This "feature" selection mechanism is clearly not scaling to newer SoCs. > >> While this patch works around the problem, IMO, we need a more scalable > >> solution. > > > > Agreed. > > > >> For features like IVA and ISP (and SGX) which are acutally IP blocks on > >> the SoC, not "features" per-se, what we really need to be doing is > >> checking for the presence of the IP block, not checking a bit in a > >> register that's not consistent across various SoCs. > >> > >> We already have all the knowledge about whether the IP blocks are > >> present in the SoC-specific hwmod data. So checking for the "feature" > >> of a specific IP block should instead be done using an > >> omap_hwmod_lookup(). > >> > >> However, there's a bit of a snag because this "feature" detection is > >> currently done before the hwmods are registered. > >> > >> As a quick-and-dirty proof of concept, the patch/hack below moves the > >> feature checking after the hwmod init (omap3 only currently) and uses > >> omap_hwmod_lookup() to check whether a given IP block exists. > >> > >> I only did a quick test on one OMAP3 platform (3430/n900) and it seems > >> to work. The init order changes need some more thought, as I didn't > >> fully validate whether the feature detection can be safely moved later > >> for all platforms. > >> > >> This is just to show the direction we should be taking this SoC > >> detection for newer SoCs. > > > > This should be coordinated with the splitting of feature detection > > as posted by Vaibhave in thread "[RFC PATCH] arm:omap: cleanup & split > > omap2/3/4_check_revision function" thread. > > Vaibhav, > > Feel free to take my proposed patch and develop it further and include > it in your rework of the SoC/feature detection. > Sorry for delayed response, This looks good approach to me, the problem is, currently in the HWMOD database we don't have all the entries, like isp or gfx/sgx. So please note that I have to first add the dummy entry for the same. Submitting RFC patch shortly. Having said that, my original patch still required, so I will submit the first patch splitting xxx_check_revision and xxx_check_features and then on top of this I will merge hwmod related patch. Thanks, Vaibhav > Kevin -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
