Aguirre, Sergio had written, on 11/20/2009 10:14 AM, the following:
-----Original Message-----
From: linux-omap-owner@xxxxxxxxxxxxxxx
[mailto:linux-omap-owner@xxxxxxxxxxxxxxx] On Behalf Of Nishanth Menon
Sent: Friday, November 20, 2009 10:10 AM
To: Pandita, Vikram
Cc: linux-omap@xxxxxxxxxxxxxxx
Subject: Re: [PATCH v3 1/2] omap: introduce
uart_no_empty_fifo_read feature
Vikram Pandita had written, on 11/20/2009 10:02 AM, the following:
Interoduce omap feature OMAP3_HAS_UART_NO_EMPTY_FIFO_READ
^^^^^^^^^ <- you meant introduce
On omap3630/omap4 an empty fifo read causes a crash
Signed-off-by: Vikram Pandita <vikram.pandita@xxxxxx>
Ack-by: Menon, Nishanth <nm@xxxxxx>
^^^^^ <- :P nope you dont have my Acked-by until you
change this to
Acked from Ack ;)..
Thanks for the simpler patch.
---
arch/arm/mach-omap2/id.c | 7 +++++++
arch/arm/plat-omap/include/plat/cpu.h | 2 ++
2 files changed, 9 insertions(+), 0 deletions(-)
diff --git a/arch/arm/mach-omap2/id.c b/arch/arm/mach-omap2/id.c
index f48a4b2..3e266cd 100644
--- a/arch/arm/mach-omap2/id.c
+++ b/arch/arm/mach-omap2/id.c
@@ -176,6 +176,12 @@ void __init omap3_check_features(void)
OMAP3_CHECK_FEATURE(status, NEON);
OMAP3_CHECK_FEATURE(status, ISP);
+ /* On omap3630 and omap4: UART empty rx fifo read aborts */
+ if (cpu_is_omap3630())
+ omap3_features |= OMAP3_HAS_UART_NO_EMPTY_FIFO_READ;
+ if (cpu_is_omap44xx())
+ omap3_features |= OMAP3_HAS_UART_NO_EMPTY_FIFO_READ;
+
Probably not something ot be attached in this patch, but...
I'm a bit curious about something:
Why touching omap3_features in OMAP4?
Isn't there a omap4_features?
Or even better, an omap_features?
yep, that is a limitation in today's FEATUREs design which we have to
fix. I see issues such as:
a) ability to scale across silicons (OMAP1 - 4)
b) differentiate between silicon feature vs erratas
c) limit to 32 bits.. meaning, we may want to think something else at a
later point..
FEATUREs is the first step in this.. we have more to go for a uniform system
Regards,
Sergio
/*
* TODO: Get additional info (where applicable)
* e.g. Size of L2 cache.
@@ -316,6 +322,7 @@ void __init omap3_cpuinfo(void)
OMAP3_SHOW_FEATURE(sgx);
OMAP3_SHOW_FEATURE(neon);
OMAP3_SHOW_FEATURE(isp);
+ OMAP3_SHOW_FEATURE(uart_no_empty_fifo_read);
printk(")\n");
}
diff --git a/arch/arm/plat-omap/include/plat/cpu.h
b/arch/arm/plat-omap/include/plat/cpu.h
index 2e17890..c32f015 100644
--- a/arch/arm/plat-omap/include/plat/cpu.h
+++ b/arch/arm/plat-omap/include/plat/cpu.h
@@ -497,6 +497,7 @@ extern u32 omap3_features;
#define OMAP3_HAS_SGX BIT(2)
#define OMAP3_HAS_NEON BIT(3)
#define OMAP3_HAS_ISP BIT(4)
+#define OMAP3_HAS_UART_NO_EMPTY_FIFO_READ BIT(5)
#define OMAP3_HAS_FEATURE(feat,flag) \
static inline unsigned int omap3_has_ ##feat(void) \
@@ -509,5 +510,6 @@ OMAP3_HAS_FEATURE(sgx, SGX)
OMAP3_HAS_FEATURE(iva, IVA)
OMAP3_HAS_FEATURE(neon, NEON)
OMAP3_HAS_FEATURE(isp, ISP)
+OMAP3_HAS_FEATURE(uart_no_empty_fifo_read, UART_NO_EMPTY_FIFO_READ)
#endif
--
Regards,
Nishanth Menon
--
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
--
Regards,
Nishanth Menon
--
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
