[PATCH 3/3] ARM: OMAP2+: gpmc: handle additional timings

[Mohammed, Afzal]

Hi Tony,

On Wed, Jun 13, 2012 at 17:28:33, Mohammed, Afzal wrote:
> On Wed, Jun 13, 2012 at 17:24:45, Tony Lindgren wrote:
> 
> > > If there's a chance it causing file system corruption, we should
> > > test it carefully on the boards before applying. If that's done,
> > > then there's probably no need for warnings. It's safer to disable
> > > NAND for untested boards if there's a chance of breaking the timings.
> > 
> > Actually this patch breaks at least DMA on tusb6010 on n8x0. That's
> > a MUSB hardware in a wrapper connected to GPMC that's very picky with
> > the timings.
> > 
> > Got any hints what should be done with the cycle2cycle stuff for
> > tusb6010?
> 
> Not as of now, let me try to find out.

Probably with the below patch [1], we can get values set by bootloader &
calculate back value to entered in Kernel, of course that may not work
if tusb6010 works with different gpmc i/p frequency.

Meanwhile, let me try to get datasheet & find proper values.
 
Regards
Afzal

diff --git a/arch/arm/mach-omap2/gpmc.c b/arch/arm/mach-omap2/gpmc.c
index eec011a..bc75e6c 100644
--- a/arch/arm/mach-omap2/gpmc.c
+++ b/arch/arm/mach-omap2/gpmc.c
@@ -336,11 +336,15 @@ int gpmc_cs_calc_divider(int cs, unsigned int sync_clk)
        return div;
 }

+static void gpmc_print_cs_timings(int cs);
+
 int gpmc_cs_set_timings(int cs, const struct gpmc_timings *t)
 {
        int div;
        u32 l;

+       gpmc_print_cs_timings(cs);
+
        div = gpmc_cs_calc_divider(cs, t->sync_clk);
        if (div < 0)
                return -1;