On 10/07/2013 04:19 PM, Nishanth Menon wrote: > On 10/03/2013 11:59 AM, Suman Anna wrote: >> The hwmod init sequence involves initializing and idling all the >> hwmods during bootup. If a module class has sysconfig, the init >> sequence utilizes the module register base for performing any >> sysc configuration. >> >> The module address space is being removed from hwmod database and >> retrieved from the <reg> property of the corresponding DT node. >> If a hwmod does not have its corresponding DT node defined and the >> memory address space is not defined in the corresponding >> omap_hwmod_ocp_if, then the module register target address space >> would be NULL and any sysc programming would result in a NULL >> pointer dereference and a kernel boot hang. >> >> Handle this scenario by checking for a valid module address space >> during the _init of each hwmod, and leaving it in the registered >> state if no module register address base is defined in either of >> the hwmod data or the DT data. >> >> Signed-off-by: Suman Anna <s-anna@xxxxxx> >> --- >> This patch helps break the dependencies between hwmod entries and >> corresponding DT entries (especially on OMAP5, where most of the >> address spaces are already cleaned up and the current data files >> have minimal entries) and fixes any boot issues due to missing >> addresses. See for reference, >> http://marc.info/?t=138005421400003&r=1&w=2 >> >> Tested on BeagleXM, Panda4, BeagleBone Black and Panda5 using >> Tero's v7 clk DT patches and Benoit's for-3.13/dts on top of >> 3.12-rc3 >> >> arch/arm/mach-omap2/omap_hwmod.c | 29 +++++++++++++++++++---------- >> 1 file changed, 19 insertions(+), 10 deletions(-) > > Mandatory to have this patch for OMAP5uEVM to boot after Tero's v7 [1] > series is merged else the delta between dts and hwmod entries cause > OMAP5 platforms to croak and die - at least worked around as seen in > [2] :( > > Tested-by: Nishanth Menon <nm@xxxxxx> > > [1] http://marc.info/?t=138009899400001&r=1&w=2 > [2] OMAP5uEVM: http://pastebin.com/jtEMwTY5 > This patch should also help Paul to be able to pick up the OMAP5 hwspinlock hwmod data [3] and would yield a similar warning without its corresponding DT node as in Nishant's log [2]. Obviously, both hwmod and DT need to be present for the associated driver to work, but atleast it doesn't hang the boot. regards Suman [3] http://marc.info/?l=linux-omap&m=138055666108306&w=2 -- 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
