Re: [PATCH 1/3] ARM: OMAP4+: hwmod data: Don't prevent RESET of USBHost module

From: Benoit Cousson
Date: Mon Dec 09 2013 - 12:52:56 EST


Salut Paul,

On 08/12/2013 17:26, Paul Walmsley wrote:
Hi Benoît,

On Tue, 3 Dec 2013, Roger Quadros wrote:

Without this, the USB devices are sometimes not detected on OMAP4 Panda
with u-boot v2013.10.

Unlike what the comment states, errata i660 does not state that we
can't RESET the USB host module. Instead it states that RESET is the
only way to recover from a deadlock situation.

RESET ensures that the module is in a known good state irrespective
of what bootloader does with the module, so it must be done at boot.

Reported-by: Tomi Valkeinen <tomi.valkeinen@xxxxxx>
Signed-off-by: Roger Quadros <rogerq@xxxxxx>

Acked-by: Paul Walmsley <paul@xxxxxxxxx>

Will you pick this up for the -rc series, or do you want me or Tony to?
Roger writes that this one's pretty important.

I guess, it is better for you to take it. I don't have anything queued for -rc.

Acked-by: Benoit Cousson <bcousson@xxxxxxxxxxxx>

Thanks,
Benoit



- Paul


---
arch/arm/mach-omap2/omap_hwmod_44xx_data.c | 12 ++----------
arch/arm/mach-omap2/omap_hwmod_54xx_data.c | 13 +++----------
2 files changed, 5 insertions(+), 20 deletions(-)

diff --git a/arch/arm/mach-omap2/omap_hwmod_44xx_data.c b/arch/arm/mach-omap2/omap_hwmod_44xx_data.c
index 1e5b12c..3318cae9 100644
--- a/arch/arm/mach-omap2/omap_hwmod_44xx_data.c
+++ b/arch/arm/mach-omap2/omap_hwmod_44xx_data.c
@@ -2937,7 +2937,7 @@ static struct omap_hwmod_class_sysconfig omap44xx_usb_host_hs_sysc = {
.sysc_offs = 0x0010,
.syss_offs = 0x0014,
.sysc_flags = (SYSC_HAS_MIDLEMODE | SYSC_HAS_SIDLEMODE |
- SYSC_HAS_SOFTRESET),
+ SYSC_HAS_SOFTRESET | SYSC_HAS_RESET_STATUS),
.idlemodes = (SIDLE_FORCE | SIDLE_NO | SIDLE_SMART |
SIDLE_SMART_WKUP | MSTANDBY_FORCE | MSTANDBY_NO |
MSTANDBY_SMART | MSTANDBY_SMART_WKUP),
@@ -3001,15 +3001,7 @@ static struct omap_hwmod omap44xx_usb_host_hs_hwmod = {
* hence HWMOD_SWSUP_MSTANDBY
*/

- /*
- * During system boot; If the hwmod framework resets the module
- * the module will have smart idle settings; which can lead to deadlock
- * (above Errata Id:i660); so, dont reset the module during boot;
- * Use HWMOD_INIT_NO_RESET.
- */
-
- .flags = HWMOD_SWSUP_SIDLE | HWMOD_SWSUP_MSTANDBY |
- HWMOD_INIT_NO_RESET,
+ .flags = HWMOD_SWSUP_SIDLE | HWMOD_SWSUP_MSTANDBY,
};

/*
diff --git a/arch/arm/mach-omap2/omap_hwmod_54xx_data.c b/arch/arm/mach-omap2/omap_hwmod_54xx_data.c
index 9e08d69..e297d62 100644
--- a/arch/arm/mach-omap2/omap_hwmod_54xx_data.c
+++ b/arch/arm/mach-omap2/omap_hwmod_54xx_data.c
@@ -1544,7 +1544,8 @@ static struct omap_hwmod_class_sysconfig omap54xx_usb_host_hs_sysc = {
.rev_offs = 0x0000,
.sysc_offs = 0x0010,
.sysc_flags = (SYSC_HAS_MIDLEMODE | SYSC_HAS_RESET_STATUS |
- SYSC_HAS_SIDLEMODE | SYSC_HAS_SOFTRESET),
+ SYSC_HAS_SIDLEMODE | SYSC_HAS_SOFTRESET |
+ SYSC_HAS_RESET_STATUS),
.idlemodes = (SIDLE_FORCE | SIDLE_NO | SIDLE_SMART |
SIDLE_SMART_WKUP | MSTANDBY_FORCE | MSTANDBY_NO |
MSTANDBY_SMART | MSTANDBY_SMART_WKUP),
@@ -1598,15 +1599,7 @@ static struct omap_hwmod omap54xx_usb_host_hs_hwmod = {
* hence HWMOD_SWSUP_MSTANDBY
*/

- /*
- * During system boot; If the hwmod framework resets the module
- * the module will have smart idle settings; which can lead to deadlock
- * (above Errata Id:i660); so, dont reset the module during boot;
- * Use HWMOD_INIT_NO_RESET.
- */
-
- .flags = HWMOD_SWSUP_SIDLE | HWMOD_SWSUP_MSTANDBY |
- HWMOD_INIT_NO_RESET,
+ .flags = HWMOD_SWSUP_SIDLE | HWMOD_SWSUP_MSTANDBY,
.main_clk = "l3init_60m_fclk",
.prcm = {
.omap4 = {
--
1.8.3.2



- Paul



--
Benoît Cousson
BayLibre
Embedded Linux Technology Lab
www.baylibre.com
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