On 05/24/2012 10:26 AM, Prafulla Wadaskar wrote:
-----Original Message----- From: Valentin Longchamp [mailto:valentin.longchamp@keymile.com] Sent: 16 May 2012 16:24 To: Prafulla Wadaskar; holger.brunck@keymile.com Cc: Valentin Longchamp; u-boot@lists.denx.de; Holger Brunck; Prafulla Wadaskar Subject: [PATCH 1/3] kirkwood: add kirkwood_mpp_save/restore functions
These 2 functions can be used in pair if one needs to set a mpp configuration only for a given time and then switch back to the previous mpp config.
Signed-off-by: Valentin Longchamp valentin.longchamp@keymile.com cc: Holger Brunck holger.brunck@keymile.com cc: Prafulla Wadaskar prafulla@marvell.com
arch/arm/cpu/arm926ejs/kirkwood/mpp.c | 18 ++++++++++++++++++ arch/arm/include/asm/arch-kirkwood/mpp.h | 2 ++ 2 files changed, 20 insertions(+), 0 deletions(-)
diff --git a/arch/arm/cpu/arm926ejs/kirkwood/mpp.c b/arch/arm/cpu/arm926ejs/kirkwood/mpp.c index 3da6c98..43f5053 100644 --- a/arch/arm/cpu/arm926ejs/kirkwood/mpp.c +++ b/arch/arm/cpu/arm926ejs/kirkwood/mpp.c @@ -80,3 +80,21 @@ void kirkwood_mpp_conf(u32 *mpp_list) debug("\n");
}
+u32 mpp_regs[MPP_NR_REGS];
This is optional feature only used in this specific case. No global here, this should be part of caller function.
I wanted this patch to be independant of the SPI claim bus that _currently_ is the only one using it, but who knows in the future.
Anyway if this isn't global here, it will have to be global in the kirkwood_spi.c driver since it would have to be shared between spi_claim_bus and spi_release_bus.
+void kirkwood_mpp_save(void)
This should be void kirkwood_mpp_save(unsigned int *mpp_ctrl, int len)
Here we save _all_ mpp registers, with direct access to the registers. With your proposed solution, I would save it in a dynamically allocated table of size len.
That's fine for me, but I would then need to export MPP_NR_REGS, because that is what I would pass as len arg, is that OK ?
+{
- int i;
- for (i = 0; i < MPP_NR_REGS; i++)
mpp_regs[i] = readl(MPP_CTRL(i));+}
+void kirkwood_mpp_restore(void)
Same here void kirkwood_mpp_restore(unsigned int *mpp_ctrl, int len)
+{
- int i;
- for (i = 0; i < MPP_NR_REGS; i++)
writel(mpp_regs[i], MPP_CTRL(i));+} diff --git a/arch/arm/include/asm/arch-kirkwood/mpp.h b/arch/arm/include/asm/arch-kirkwood/mpp.h index b3c090e..da65b4d 100644 --- a/arch/arm/include/asm/arch-kirkwood/mpp.h +++ b/arch/arm/include/asm/arch-kirkwood/mpp.h @@ -313,5 +313,7 @@ #define MPP_MAX 49
void kirkwood_mpp_conf(unsigned int *mpp_list); +void kirkwood_mpp_save(void); +void kirkwood_mpp_restore(void);
Regards.. Prafulla . . .