[PATCH] ARM: AM33xx: add support for reboot

[Hiremath, Vaibhav]

On Sun, Oct 28, 2012 at 23:47:55, Daniel Mack wrote:
> This patch adds the ability to reboot am33xx-based systems.
> 
> Signed-off-by: Daniel Mack <zonque at gmail.com>
> ---
>  arch/arm/mach-omap2/board-generic.c | 1 +
>  arch/arm/mach-omap2/prcm.c          | 6 ++++++
>  2 files changed, 7 insertions(+)
> 
> diff --git a/arch/arm/mach-omap2/board-generic.c b/arch/arm/mach-omap2/board-generic.c
> index 601ecdf..6a69ceb 100644
> --- a/arch/arm/mach-omap2/board-generic.c
> +++ b/arch/arm/mach-omap2/board-generic.c
> @@ -114,6 +114,7 @@ DT_MACHINE_START(AM33XX_DT, "Generic AM33XX (Flattened Device Tree)")
>  	.init_machine	= omap_generic_init,
>  	.timer		= &omap3_am33xx_timer,
>  	.dt_compat	= am33xx_boards_compat,
> +	.restart	= omap_prcm_restart,
>  MACHINE_END
>  #endif
>  
> diff --git a/arch/arm/mach-omap2/prcm.c b/arch/arm/mach-omap2/prcm.c
> index 0f51e03..8a3068a 100644
> --- a/arch/arm/mach-omap2/prcm.c
> +++ b/arch/arm/mach-omap2/prcm.c
> @@ -32,6 +32,7 @@
>  #include "clock2xxx.h"
>  #include "cm2xxx_3xxx.h"
>  #include "prm2xxx_3xxx.h"
> +#include "prm33xx.h"
>  #include "prm44xx.h"
>  #include "prminst44xx.h"
>  #include "cminst44xx.h"
> @@ -72,6 +73,11 @@ void omap_prcm_restart(char mode, const char *cmd)
>  		omap3_ctrl_write_boot_mode((cmd ? (u8)*cmd : 0));
>  	} else if (cpu_is_omap44xx()) {
>  		omap4_prminst_global_warm_sw_reset(); /* never returns */
> +	} else if (soc_is_am33xx()) {
> +		prcm_offs = AM33XX_PRM_DEVICE_MOD;
> +		omap2_prm_set_mod_reg_bits(OMAP4430_RST_GLOBAL_COLD_SW_MASK,
> +					   prcm_offs,
> +					   AM33XX_PRM_RSTCTRL_OFFSET);

This is not clean way of handling it, we should have something similar to 
omap4. Also we should use warm-reset here instead of cold.

I have quickly created patch, can you please review and test is?
I have tested it on AM335x EVM and Bone platform.


diff --git a/arch/arm/mach-omap2/board-generic.c b/arch/arm/mach-omap2/board-generic.c
index 601ecdf..6a69ceb 100644
--- a/arch/arm/mach-omap2/board-generic.c
+++ b/arch/arm/mach-omap2/board-generic.c
@@ -114,6 +114,7 @@ DT_MACHINE_START(AM33XX_DT, "Generic AM33XX (Flattened Device Tree)")
        .init_machine   = omap_generic_init,
        .timer          = &omap3_am33xx_timer,
        .dt_compat      = am33xx_boards_compat,
+       .restart        = omap_prcm_restart,
 MACHINE_END
 #endif

diff --git a/arch/arm/mach-omap2/prcm.c b/arch/arm/mach-omap2/prcm.c
index 0f51e03..490f8f6 100644
--- a/arch/arm/mach-omap2/prcm.c
+++ b/arch/arm/mach-omap2/prcm.c
@@ -33,6 +33,7 @@
 #include "cm2xxx_3xxx.h"
 #include "prm2xxx_3xxx.h"
 #include "prm44xx.h"
+#include "prm33xx.h"
 #include "prminst44xx.h"
 #include "cminst44xx.h"
 #include "prm-regbits-24xx.h"
@@ -72,6 +73,8 @@ void omap_prcm_restart(char mode, const char *cmd)
                omap3_ctrl_write_boot_mode((cmd ? (u8)*cmd : 0));
        } else if (cpu_is_omap44xx()) {
                omap4_prminst_global_warm_sw_reset(); /* never returns */
+       } else if (soc_is_am33xx()) {
+               am33xx_prm_global_warm_sw_reset();      /* never returns */
        } else {
                WARN_ON(1);
        }
diff --git a/arch/arm/mach-omap2/prm33xx.c b/arch/arm/mach-omap2/prm33xx.c
index e7dbb6c..505219d 100644
--- a/arch/arm/mach-omap2/prm33xx.c
+++ b/arch/arm/mach-omap2/prm33xx.c
@@ -133,3 +133,18 @@ int am33xx_prm_deassert_hardreset(u8 shift, s16 inst,

        return (c == MAX_MODULE_HARDRESET_WAIT) ? -EBUSY : 0;
 }
+
+void am33xx_prm_global_warm_sw_reset(void)
+{
+       u32 v;
+
+       v = am33xx_prm_read_reg(AM33XX_PRM_DEVICE_MOD,
+                                   AM33XX_PRM_RSTCTRL_OFFSET);
+       v |= AM33XX_GLOBAL_WARM_SW_RST_MASK;
+       am33xx_prm_write_reg(v, AM33XX_PRM_DEVICE_MOD,
+                                AM33XX_PRM_RSTCTRL_OFFSET);
+
+       /* OCP barrier */
+       v = am33xx_prm_read_reg(AM33XX_PRM_DEVICE_MOD,
+                                   AM33XX_PRM_RSTCTRL_OFFSET);
+}
diff --git a/arch/arm/mach-omap2/prm33xx.h b/arch/arm/mach-omap2/prm33xx.h
index 3f25c56..cdfc694 100644
--- a/arch/arm/mach-omap2/prm33xx.h
+++ b/arch/arm/mach-omap2/prm33xx.h
@@ -126,4 +126,5 @@ extern int am33xx_prm_is_hardreset_asserted(u8 shift, s16 inst,
 extern int am33xx_prm_assert_hardreset(u8 shift, s16 inst, u16 rstctrl_offs);
 extern int am33xx_prm_deassert_hardreset(u8 shift, s16 inst,
                u16 rstctrl_offs, u16 rstst_offs);
+extern void am33xx_prm_global_warm_sw_reset(void);


Thanks,
Vaibhav