From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Extend early prink code to be able to handle other SCIF(X)
compatible interfaces as well. These interfaces have lot in common,
but mostly differ in offsets and bits for some registers.
Introduce "EARLY_PRINTK_VERSION" config option to choose which
interface version should be used (to properly apply register offsets).
Please note, nothing has been technically changed for Renesas "Lager"
and other supported boards (SCIF).
The "EARLY_PRINTK_VERSION" option for that board should be empty:
CONFIG_EARLY_PRINTK=scif,0xe6e60000
Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
CC: Julien Grall <julien.grall@arm.com>
---
Changes in v3:
- It was decided not to introduce new debug-scifa.inc
for handling SCIFA interface, but to extend existing
debug-scif.inc for handling both interfaces.
This patch is a result of splitting an initial patch
"xen/arm: Add SCIFA UART support for early printk"
and only reworks a code
Changes in v4:
- Update docs/misc/arm/early-printk.txt with the new option
---
docs/misc/arm/early-printk.txt | 6 ++++++
xen/arch/arm/Rules.mk | 7 +++++++
xen/arch/arm/arm32/debug-scif.inc | 13 +++++++++----
3 files changed, 22 insertions(+), 4 deletions(-)
diff --git a/docs/misc/arm/early-printk.txt b/docs/misc/arm/early-printk.txt
index b23c54f..c054674 100644
--- a/docs/misc/arm/early-printk.txt
+++ b/docs/misc/arm/early-printk.txt
@@ -27,6 +27,12 @@ CONFIG_EARLY_PRINTK=<INC>,<BASE_ADDRESS>,<OTHER_OPTIONS>
If <BAUD_RATE> is not given then the code will not try to
initialize the UART, so that bootloader or firmware settings can
be used for maximum compatibility.
+ - scif,<BASE_ADDRESS>,<VERSION>
+ - <VERSION> is a option to choose which interface version should be used
+ on a target board.
+
+ If <VERSION> is not given then a default interface version (SCIF)
+ will be used.
- For all other uarts there are no additional options.
As a convenience it is also possible to select from a list of
diff --git a/xen/arch/arm/Rules.mk b/xen/arch/arm/Rules.mk
index f264592..3d9a0ed 100644
--- a/xen/arch/arm/Rules.mk
+++ b/xen/arch/arm/Rules.mk
@@ -68,6 +68,13 @@ EARLY_PRINTK_INIT_UART := y
EARLY_PRINTK_BAUD := $(word 3,$(EARLY_PRINTK_CFG))
endif
endif
+ifeq ($(EARLY_PRINTK_INC),scif)
+ifneq ($(word 3,$(EARLY_PRINTK_CFG)),)
+CFLAGS-y += -DEARLY_PRINTK_VERSION_$(word 3,$(EARLY_PRINTK_CFG))
+else
+CFLAGS-y += -DEARLY_PRINTK_VERSION_NONE
+endif
+endif
ifneq ($(EARLY_PRINTK_INC),)
EARLY_PRINTK := y
diff --git a/xen/arch/arm/arm32/debug-scif.inc b/xen/arch/arm/arm32/debug-scif.inc
index 143f05d..a8d2eae 100644
--- a/xen/arch/arm/arm32/debug-scif.inc
+++ b/xen/arch/arm/arm32/debug-scif.inc
@@ -19,6 +19,11 @@
#include <asm/scif-uart.h>
+#ifdef EARLY_PRINTK_VERSION_NONE
+#define STATUS_REG SCIF_SCFSR
+#define TX_FIFO_REG SCIF_SCFTDR
+#endif
+
/*
* SCIF UART wait UART to be ready to transmit
* rb: register which contains the UART base address
@@ -26,7 +31,7 @@
*/
.macro early_uart_ready rb rc
1:
- ldrh \rc, [\rb, #SCIF_SCFSR] /* <- SCFSR (status register) */
+ ldrh \rc, [\rb, #STATUS_REG] /* Read status register */
tst \rc, #SCFSR_TDFE /* Check TDFE bit */
beq 1b /* Wait for the UART to be ready */
.endm
@@ -37,10 +42,10 @@
* rt: register which contains the character to transmit
*/
.macro early_uart_transmit rb rt
- strb \rt, [\rb, #SCIF_SCFTDR] /* -> SCFTDR (data register) */
- ldrh \rt, [\rb, #SCIF_SCFSR] /* <- SCFSR (status register) */
+ strb \rt, [\rb, #TX_FIFO_REG] /* Write data register */
+ ldrh \rt, [\rb, #STATUS_REG] /* Read status register */
and \rt, \rt, #(~(SCFSR_TEND | SCFSR_TDFE)) /* Clear TEND and TDFE bits */
- strh \rt, [\rb, #SCIF_SCFSR] /* -> SCFSR (status register) */
+ strh \rt, [\rb, #STATUS_REG] /* Write status register */
.endm
/*
--
2.7.4
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Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-develHi Oleksandr, On 17/04/2019 15:59, Oleksandr Tyshchenko wrote: > From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> > > Extend early prink code to be able to handle other SCIF(X) > compatible interfaces as well. These interfaces have lot in common, > but mostly differ in offsets and bits for some registers. > > Introduce "EARLY_PRINTK_VERSION" config option to choose which > interface version should be used (to properly apply register offsets). > > Please note, nothing has been technically changed for Renesas "Lager" > and other supported boards (SCIF). > > The "EARLY_PRINTK_VERSION" option for that board should be empty: > CONFIG_EARLY_PRINTK=scif,0xe6e60000 > > Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> > CC: Julien Grall <julien.grall@arm.com> > > --- > Changes in v3: > - It was decided not to introduce new debug-scifa.inc > for handling SCIFA interface, but to extend existing > debug-scif.inc for handling both interfaces. > This patch is a result of splitting an initial patch > "xen/arm: Add SCIFA UART support for early printk" > and only reworks a code > > Changes in v4: > - Update docs/misc/arm/early-printk.txt with the new option > --- > docs/misc/arm/early-printk.txt | 6 ++++++ > xen/arch/arm/Rules.mk | 7 +++++++ > xen/arch/arm/arm32/debug-scif.inc | 13 +++++++++---- > 3 files changed, 22 insertions(+), 4 deletions(-) > > diff --git a/docs/misc/arm/early-printk.txt b/docs/misc/arm/early-printk.txt > index b23c54f..c054674 100644 > --- a/docs/misc/arm/early-printk.txt > +++ b/docs/misc/arm/early-printk.txt > @@ -27,6 +27,12 @@ CONFIG_EARLY_PRINTK=<INC>,<BASE_ADDRESS>,<OTHER_OPTIONS> > If <BAUD_RATE> is not given then the code will not try to > initialize the UART, so that bootloader or firmware settings can > be used for maximum compatibility. > + - scif,<BASE_ADDRESS>,<VERSION> > + - <VERSION> is a option to choose which interface version should be used By "a option" did you intend to mean it is an optional parameter? If so, how about: "SCIF<VERSION> is, optionally, the interface version of the UART." So you would also provide a way for the user to know how to specify it. Stefano any opinion? > + If <VERSION> is not given then a default interface version (SCIF) s/a/the/ > + will be used. > - For all other uarts there are no additional options. > > As a convenience it is also possible to select from a list of > diff --git a/xen/arch/arm/Rules.mk b/xen/arch/arm/Rules.mk > index f264592..3d9a0ed 100644 > --- a/xen/arch/arm/Rules.mk > +++ b/xen/arch/arm/Rules.mk > @@ -68,6 +68,13 @@ EARLY_PRINTK_INIT_UART := y > EARLY_PRINTK_BAUD := $(word 3,$(EARLY_PRINTK_CFG)) > endif > endif > +ifeq ($(EARLY_PRINTK_INC),scif) > +ifneq ($(word 3,$(EARLY_PRINTK_CFG)),) > +CFLAGS-y += -DEARLY_PRINTK_VERSION_$(word 3,$(EARLY_PRINTK_CFG)) > +else > +CFLAGS-y += -DEARLY_PRINTK_VERSION_NONE > +endif > +endif > > ifneq ($(EARLY_PRINTK_INC),) > EARLY_PRINTK := y > diff --git a/xen/arch/arm/arm32/debug-scif.inc b/xen/arch/arm/arm32/debug-scif.inc > index 143f05d..a8d2eae 100644 > --- a/xen/arch/arm/arm32/debug-scif.inc > +++ b/xen/arch/arm/arm32/debug-scif.inc > @@ -19,6 +19,11 @@ > > #include <asm/scif-uart.h> > > +#ifdef EARLY_PRINTK_VERSION_NONE > +#define STATUS_REG SCIF_SCFSR > +#define TX_FIFO_REG SCIF_SCFTDR > +#endif > + > /* > * SCIF UART wait UART to be ready to transmit > * rb: register which contains the UART base address > @@ -26,7 +31,7 @@ > */ > .macro early_uart_ready rb rc > 1: > - ldrh \rc, [\rb, #SCIF_SCFSR] /* <- SCFSR (status register) */ > + ldrh \rc, [\rb, #STATUS_REG] /* Read status register */ > tst \rc, #SCFSR_TDFE /* Check TDFE bit */ > beq 1b /* Wait for the UART to be ready */ > .endm > @@ -37,10 +42,10 @@ > * rt: register which contains the character to transmit > */ > .macro early_uart_transmit rb rt > - strb \rt, [\rb, #SCIF_SCFTDR] /* -> SCFTDR (data register) */ > - ldrh \rt, [\rb, #SCIF_SCFSR] /* <- SCFSR (status register) */ > + strb \rt, [\rb, #TX_FIFO_REG] /* Write data register */ > + ldrh \rt, [\rb, #STATUS_REG] /* Read status register */ > and \rt, \rt, #(~(SCFSR_TEND | SCFSR_TDFE)) /* Clear TEND and TDFE bits */ > - strh \rt, [\rb, #SCIF_SCFSR] /* -> SCFSR (status register) */ > + strh \rt, [\rb, #STATUS_REG] /* Write status register */ > .endm > > /* > CHeers, -- Julien Grall _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
On 29.04.19 17:29, Julien Grall wrote: > Hi Oleksandr, Hi Julien > >> --- >> docs/misc/arm/early-printk.txt | 6 ++++++ >> xen/arch/arm/Rules.mk | 7 +++++++ >> xen/arch/arm/arm32/debug-scif.inc | 13 +++++++++---- >> 3 files changed, 22 insertions(+), 4 deletions(-) >> >> diff --git a/docs/misc/arm/early-printk.txt >> b/docs/misc/arm/early-printk.txt >> index b23c54f..c054674 100644 >> --- a/docs/misc/arm/early-printk.txt >> +++ b/docs/misc/arm/early-printk.txt >> @@ -27,6 +27,12 @@ >> CONFIG_EARLY_PRINTK=<INC>,<BASE_ADDRESS>,<OTHER_OPTIONS> >> If <BAUD_RATE> is not given then the code will not try to >> initialize the UART, so that bootloader or firmware settings can >> be used for maximum compatibility. >> + - scif,<BASE_ADDRESS>,<VERSION> >> + - <VERSION> is a option to choose which interface version should >> be used > > By "a option" did you intend to mean it is an optional parameter? > > If so, how about: > > "SCIF<VERSION> is, optionally, the interface version of the UART." agree. will change. > > So you would also provide a way for the user to know how to specify > it. Stefano any opinion? I am going to update Wiki page regarding how to run Stout board on Xen and how to properly enable earlyprintk support on that board. Would it be enough? Also I can add a note to patch description. In V1 I added convenient alias EARLY_PRINTK_stout, but AFAIR it was decided to avoid adding new aliases. > >> + If <VERSION> is not given then a default interface version (SCIF) > > s/a/the/ ok -- Regards, Oleksandr Tyshchenko _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
Hi, On 4/30/19 12:00 PM, Oleksandr wrote: > > On 29.04.19 17:29, Julien Grall wrote: >> Hi Oleksandr, > > Hi Julien > > >> >>> --- >>> docs/misc/arm/early-printk.txt | 6 ++++++ >>> xen/arch/arm/Rules.mk | 7 +++++++ >>> xen/arch/arm/arm32/debug-scif.inc | 13 +++++++++---- >>> 3 files changed, 22 insertions(+), 4 deletions(-) >>> >>> diff --git a/docs/misc/arm/early-printk.txt >>> b/docs/misc/arm/early-printk.txt >>> index b23c54f..c054674 100644 >>> --- a/docs/misc/arm/early-printk.txt >>> +++ b/docs/misc/arm/early-printk.txt >>> @@ -27,6 +27,12 @@ >>> CONFIG_EARLY_PRINTK=<INC>,<BASE_ADDRESS>,<OTHER_OPTIONS> >>> If <BAUD_RATE> is not given then the code will not try to >>> initialize the UART, so that bootloader or firmware settings can >>> be used for maximum compatibility. >>> + - scif,<BASE_ADDRESS>,<VERSION> >>> + - <VERSION> is a option to choose which interface version should >>> be used >> >> By "a option" did you intend to mean it is an optional parameter? >> >> If so, how about: >> >> "SCIF<VERSION> is, optionally, the interface version of the UART." > > agree. will change. > > >> >> So you would also provide a way for the user to know how to specify >> it. Stefano any opinion? > > I am going to update Wiki page regarding how to run Stout board on Xen > and how to properly enable earlyprintk support on that board. My point was not adding new alias (I am not in favor anyway), but giving hint to the user how infer the value of <VERSION>. The wiki page for the board can then explain a bit more into details how to setup earlyprintk. Cheers, -- Julien Grall _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
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