Thanks for comments Catalin !! > -----Original Message----- > From: Catalin Marinas [mailto:catalin.marinas@xxxxxxx] > Sent: Monday, December 14, 2009 4:07 PM > To: Shilimkar, Santosh > Cc: tony@xxxxxxxxxxx; linux-omap@xxxxxxxxxxxxxxx; linux@xxxxxxxxxxxxxxxx; linux-arm- > kernel@xxxxxxxxxxxxxxxxxxx > Subject: Re: [PATCH 3/4] ARM: L2 : Errata 588369: Clean & Invalidate do notinvalidate clean lines > > On Wed, 2009-12-09 at 18:43 +0000, Santosh Shilimkar wrote: > > This patch implements the work-around for the errata 588369. The secure API > > is used to alter L2 debug regsiter because of trust-zone. > [...] > > +config PL310_ERRATA_588369 > > + bool "Clean & Invalidate maintenance operations do not invalidate clean lines" > > + depends on CACHE_L2X0 > > + default n > > + help > > + The PL310 L2 cache controller implements three types of Clean & > > + Invalidate maintenance operations: by Physical Address > > + (offset 0x7F0), by Index/Way (0x7F8) and by Way (0x7FC). > > + They are architecturally defined to behave as the execution of a > > + clean operation followed immediately by an invalidate operation, > > + both performing to the same memory location. This functionality > > + is not correctly implemented in PL310 as clean lines are not > > + invalidated as a result of these operations > > endmenu > > Could you actually add a comment and a dependence on OMAP4 since this > requires the secure monitor that only TI has. OK > > +#ifdef CONFIG_PL310_ERRATA_588369 > > + /* > > + * Disable Write-Back and Cache Linefill (set bits [1:0] of the Debug > > + * Control Register) > > + */ > > + __asm__ __volatile__( > > + "stmfd r13!, {r0-r12, r14}\n" > > + "mov r0, #3\n" > > + "ldr r12, =0x100\n" > > + "dsb\n" > > + "smc\n" > > + "ldmfd r13!, {r0-r12, r14}"); > > Could you actually add a function that gets called with a parameter > rather than having to similar inline asm blocks? You also don't need to > save/restore the registers if you declare them properly or use local > variables for that, the compiler does the work for you. A function call would be better as you suggested. We will look into this. > Is a DSB needed before SMC (I'm not sure)? That was a recommendation though not having it, I didn't observer any problems. > -- > Catalin -- 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
