[RESEND PATCH v2] ARM: debug: add support for Palmchip BK-310x UART

Marc Gonzalez [off-list ref] writes:

On 27/01/2016 01:44, M?ns Rullg?rd wrote:

quoted

Kevin Hilman [off-list ref] writes:

quoted

Marc Gonzalez [off-list ref] writes:

quoted

From: Mans Rullgard <redacted>

Some SoCs use a Palmchip BK-310x UART which is mostly 16550 compatible
but with a different register layout.

... because UART register layout is where we really need innovation. ;)

quoted

While this UART has previously
only been supported in MIPS based chips (Alchemy, Ralink), the ARM based
SMP87xx series from Sigma Designs also uses it.

This patch allows the debug console to work with this type of UART.

Signed-off-by: Mans Rullgard <redacted>
Signed-off-by: Marc Gonzalez <redacted>

It appears this was previously acked by Arnd also?
https://lkml.org/lkml/2015/11/9/116

quoted

---
Peter, this is the patch I've been using on Tango for earlyprintk support.
arm-soc, this is just the Nov 8 patch with my Signed-off-by tag.
---
 arch/arm/Kconfig.debug            |  9 +++++++++
 arch/arm/include/debug/palmchip.S | 11 +++++++++++
 2 files changed, 20 insertions(+)
 create mode 100644 arch/arm/include/debug/palmchip.S

diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug
index 259c0ca9c99a..708aa9150c00 100644
--- a/arch/arm/Kconfig.debug
+++ b/arch/arm/Kconfig.debug

@@ -1304,6 +1304,7 @@ config DEBUG_SIRFSOC_UART
 config DEBUG_LL_INCLUDE
 	string
 	default "debug/sa1100.S" if DEBUG_SA1100
+	default "debug/palmchip.S" if DEBUG_UART_8250_PALMCHIP

minor nit: We're trying (not always with great success) to keep various
parts of this file sorted alphanumerically.  Can you please insert the
new entries accordingly?

It has to precede the regular 8250 entry so as to take precedence over
that.

<confused> Are you all talking about these 2 lines:

	default "debug/palmchip.S" if DEBUG_UART_8250_PALMCHIP
	default "debug/8250.S" if DEBUG_LL_UART_8250 || DEBUG_UART_8250

default "debug/palmchip.S" is supposed to come before default "debug/8250.S" ?

Because, in my config, there is no DEBUG_LL_UART_8250 to be seen, and
# CONFIG_DEBUG_UART_8250 is not set

CONFIG_DEBUG_LL_UART_8250=y here.  In fact DEBUG_UART_8250_PALMCHIP
depends on "DEBUG_LL_UART_8250 || DEBUG_UART_8250" so one of those
*must* be set for any of this to matter.

-- 
M?ns Rullg?rd

On 29/01/2016 17:50, M?ns Rullg?rd wrote:

Marc Gonzalez [off-list ref] writes:

quoted

On 27/01/2016 01:44, M?ns Rullg?rd wrote:

quoted

Kevin Hilman [off-list ref] writes:

quoted

Marc Gonzalez [off-list ref] writes:

quoted

From: Mans Rullgard <redacted>

Some SoCs use a Palmchip BK-310x UART which is mostly 16550 compatible
but with a different register layout.

... because UART register layout is where we really need innovation. ;)

quoted

While this UART has previously
only been supported in MIPS based chips (Alchemy, Ralink), the ARM based
SMP87xx series from Sigma Designs also uses it.

This patch allows the debug console to work with this type of UART.

Signed-off-by: Mans Rullgard <redacted>
Signed-off-by: Marc Gonzalez <redacted>

It appears this was previously acked by Arnd also?
https://lkml.org/lkml/2015/11/9/116

quoted

---
Peter, this is the patch I've been using on Tango for earlyprintk support.
arm-soc, this is just the Nov 8 patch with my Signed-off-by tag.
---
 arch/arm/Kconfig.debug            |  9 +++++++++
 arch/arm/include/debug/palmchip.S | 11 +++++++++++
 2 files changed, 20 insertions(+)
 create mode 100644 arch/arm/include/debug/palmchip.S

diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug
index 259c0ca9c99a..708aa9150c00 100644
--- a/arch/arm/Kconfig.debug
+++ b/arch/arm/Kconfig.debug

@@ -1304,6 +1304,7 @@ config DEBUG_SIRFSOC_UART
 config DEBUG_LL_INCLUDE
 	string
 	default "debug/sa1100.S" if DEBUG_SA1100
+	default "debug/palmchip.S" if DEBUG_UART_8250_PALMCHIP

minor nit: We're trying (not always with great success) to keep various
parts of this file sorted alphanumerically.  Can you please insert the
new entries accordingly?

It has to precede the regular 8250 entry so as to take precedence over
that.

<confused> Are you all talking about these 2 lines:

	default "debug/palmchip.S" if DEBUG_UART_8250_PALMCHIP
	default "debug/8250.S" if DEBUG_LL_UART_8250 || DEBUG_UART_8250

default "debug/palmchip.S" is supposed to come before default "debug/8250.S" ?

Because, in my config, there is no DEBUG_LL_UART_8250 to be seen, and
# CONFIG_DEBUG_UART_8250 is not set

CONFIG_DEBUG_LL_UART_8250=y here.  In fact DEBUG_UART_8250_PALMCHIP
depends on "DEBUG_LL_UART_8250 || DEBUG_UART_8250" so one of those
*must* be set for any of this to matter.

Doh! I was looking at a config where earlyprintk isn't enabled... o_O

config DEBUG_UART_8250_PALMCHIP
	bool "8250 UART is Palmchip BK-310x"
	depends on DEBUG_LL_UART_8250 || DEBUG_UART_8250

OK, I understand now. Thanks.

Regards.