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Allow using machine ID for DEBUG_LL macros

PATCH New Tony Lindgren 3 participants 12 messages Feb 4, 2011

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Arm (32-bit) Arm sub-architectures Arm i.MX and Layerscape Arm Samsung Exynos +16 more subsystems
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Tony Lindgren

author maintainer
#0 lore raw

cover Allow using machine ID for DEBUG_LL macros

Hi all,

Here are two patches that allow using machine ID for DEBUG_LL macros by adding a new macro inituart.

Will post the related omap changes separately.

Regards,

Tony

---

Tony Lindgren (2):
ARM: Add inituart macro to initialize DEBUG_LL serial port based on the machine ID
ARM: Add empty inituart macros

 arch/arm/kernel/head-common.S                      |    7 +++++++
 arch/arm/kernel/head.S                             |    5 +++++
 arch/arm/mach-aaec2000/include/mach/debug-macro.S  |    4 ++++
 arch/arm/mach-at91/include/mach/debug-macro.S      |    3 +++
 arch/arm/mach-clps711x/include/mach/debug-macro.S  |    3 +++
 arch/arm/mach-cns3xxx/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-davinci/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-dove/include/mach/debug-macro.S      |    3 +++
 arch/arm/mach-ebsa110/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-ep93xx/include/mach/debug-macro.S    |    3 +++
 .../arm/mach-footbridge/include/mach/debug-macro.S |    4 ++++
 arch/arm/mach-gemini/include/mach/debug-macro.S    |    3 +++
 .../arm/mach-integrator/include/mach/debug-macro.S |    3 +++
 arch/arm/mach-iop13xx/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-iop32x/include/mach/debug-macro.S    |    3 +++
 arch/arm/mach-iop33x/include/mach/debug-macro.S    |    3 +++
 arch/arm/mach-ixp23xx/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-kirkwood/include/mach/debug-macro.S  |    3 +++
 arch/arm/mach-ks8695/include/mach/debug-macro.S    |    3 +++
 arch/arm/mach-l7200/include/mach/debug-macro.S     |    3 +++
 arch/arm/mach-loki/include/mach/debug-macro.S      |    3 +++
 arch/arm/mach-lpc32xx/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-mmp/include/mach/debug-macro.S       |    3 +++
 arch/arm/mach-msm/include/mach/debug-macro.S       |    4 ++++
 arch/arm/mach-mv78xx0/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-mxs/include/mach/debug-macro.S       |    3 +++
 arch/arm/mach-netx/include/mach/debug-macro.S      |    3 +++
 arch/arm/mach-nomadik/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-ns9xxx/include/mach/debug-macro.S    |    3 +++
 arch/arm/mach-omap1/include/mach/debug-macro.S     |    3 +++
 arch/arm/mach-omap2/include/mach/debug-macro.S     |    3 +++
 arch/arm/mach-pnx4008/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-pxa/include/mach/debug-macro.S       |    3 +++
 arch/arm/mach-realview/include/mach/debug-macro.S  |    3 +++
 arch/arm/mach-rpc/include/mach/debug-macro.S       |    3 +++
 arch/arm/mach-s3c2410/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-s3c24a0/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-s3c64xx/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-s5p6442/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-s5p64x0/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-s5pc100/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-s5pv210/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-s5pv310/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-sa1100/include/mach/debug-macro.S    |    3 +++
 arch/arm/mach-shark/include/mach/debug-macro.S     |    3 +++
 arch/arm/mach-u300/include/mach/debug-macro.S      |    3 +++
 arch/arm/mach-ux500/include/mach/debug-macro.S     |    3 +++
 arch/arm/mach-versatile/include/mach/debug-macro.S |    3 +++
 arch/arm/mach-vexpress/include/mach/debug-macro.S  |    3 +++
 arch/arm/plat-mxc/include/mach/debug-macro.S       |    3 +++
 arch/arm/plat-spear/include/plat/debug-macro.S     |    3 +++
 arch/arm/plat-stmp3xxx/include/mach/debug-macro.S  |    3 +++
 arch/arm/plat-tcc/include/mach/debug-macro.S       |    3 +++
 53 files changed, 168 insertions(+), 0 deletions(-)
Signature · 1 line
Signature
author maintainer
#1 lore raw

PATCH 1/2 ARM: Add inituart macro to initialize DEBUG_LL serial port based on the machine ID

Allow machine specific init of the DEBUG_LL serial port. This is needed to debug kernels built with support for multiple machines compiled in without recompiling the kernel.

As some SoCs need to use variables to store the port address and LSR register configuration, we must call inituart again after clearing the BSS.

If variables are being used for for inituart and addruart, this setup won't work properly for debugging the uncompress code without patching arch/arm/boot/compressed/head.S for the machine in question.

For adding DEBUG_LL support for new machines, only two lines are needed in debug-macro.S:

	.macro	inituart, id, a, v
	...
	ldr	\v, =MACH_TYPE_SOMETHING1
	cmp	\id, \v
	ldrne	\v, =MACH_TYPE_SOMETHING2
	cmpne	\id, \v
	ldrne	\v, =MACH_TYPE_SOMETHING3
	cmpne	\id, \v
	...
	.endm

Note that this patch depends on a patch to add empty inituart macro for each debug-macro.S file.

Signed-off-by Tony Lindgren <[email protected]>
---
 arch/arm/kernel/head-common.S |    7 +++++++
 arch/arm/kernel/head.S        |    5 +++++
 2 files changed, 12 insertions(+), 0 deletions(-)
arch/arm/kernel/head-common.S +7 -0
index c84b57d..0b66d6b 100644
@@ -63,6 +63,9 @@ ENDPROC(__vet_atags)
  *  r1  = machine ID
  *  r2  = atags pointer
  *  r9  = processor ID
+ *
+ * Note that if the machine uses BSS to store the debug UART configuration,
+ * debug_ll code will not work after clear BSS until inituart is called again.
  */
 	__INIT
 __mmap_switched:

@@ -80,6 +83,10 @@ __mmap_switched:
 	strcc	fp, [r6],#4
 	bcc	1b
 
+#if defined(CONFIG_DEBUG_LL) && !defined(CONFIG_DEBUG_ICEDCC)
+	inituart r1, r4, r5
+#endif
+
  ARM(	ldmia	r3, {r4, r5, r6, r7, sp})
  THUMB(	ldmia	r3, {r4, r5, r6, r7}	)
  THUMB(	ldr	sp, [r3, #16]		)
arch/arm/kernel/head.S +5 -0
index 591a2ea..be64264 100644
@@ -75,6 +75,11 @@
 ENTRY(stext)
 	setmode	PSR_F_BIT | PSR_I_BIT | SVC_MODE, r9 @ ensure svc mode
 						@ and irqs disabled
+
+#if defined(CONFIG_DEBUG_LL) && !defined(CONFIG_DEBUG_ICEDCC)
+	inituart r1, r3, r4
+#endif
+
 	mrc	p15, 0, r9, c0, c0		@ get processor id
 	bl	__lookup_processor_type		@ r5=procinfo r9=cpuid
 	movs	r10, r5				@ invalid processor (r5=0)?
#2 lore raw

PATCH 1/2 ARM: Add inituart macro to initialize DEBUG_LL serial port based on the machine ID

Quoted 40 lines · Tony Lindgren

Allow machine specific init of the DEBUG_LL serial port. This is needed to debug kernels built with support for multiple machines compiled in without recompiling the kernel.

As some SoCs need to use variables to store the port address and LSR register configuration, we must call inituart again after clearing the BSS.

If variables are being used for for inituart and addruart, this setup won't work properly for debugging the uncompress code without patching arch/arm/boot/compressed/head.S for the machine in question.

For adding DEBUG_LL support for new machines, only two lines are needed in debug-macro.S:

	.macro	inituart, id, a, v
	...
	ldr	\v, =MACH_TYPE_SOMETHING1
	cmp	\id, \v
	ldrne	\v, =MACH_TYPE_SOMETHING2
	cmpne	\id, \v
	ldrne	\v, =MACH_TYPE_SOMETHING3
	cmpne	\id, \v
	...
	.endm

Note that this patch depends on a patch to add empty inituart macro for each debug-macro.S file.

Signed-off-by Tony Lindgren <[email protected]>
---
 arch/arm/kernel/head-common.S |    7 +++++++
 arch/arm/kernel/head.S        |    5 +++++
 2 files changed, 12 insertions(+), 0 deletions(-)
arch/arm/kernel/head-common.S +0 -0
index c84b57d..0b66d6b 100644

arch/arm/kernel/head-common.S ENDPROC(__vet_atags) · line 69

Quoted 7 lines
arch/arm/kernel/head-common.S +3 -0
@@ -63,6 +63,9 @@ ENDPROC(__vet_atags)
  *  r1  = machine ID
  *  r2  = atags pointer
  *  r9  = processor ID
+ *
+ * Note that if the machine uses BSS to store the debug UART configuration,
+ * debug_ll code will not work after clear BSS until inituart is called again.
  */

Please make sure that inituart always uses .data to store its needed configuration instead.

Quoted 18 lines
arch/arm/kernel/head-common.S +4 -0
 	__INIT
 __mmap_switched:

@@ -80,6 +83,10 @@ __mmap_switched:
 	strcc	fp, [r6],#4
 	bcc	1b
 
+#if defined(CONFIG_DEBUG_LL) && !defined(CONFIG_DEBUG_ICEDCC)
+	inituart r1, r4, r5
+#endif
+
  ARM(	ldmia	r3, {r4, r5, r6, r7, sp})
  THUMB(	ldmia	r3, {r4, r5, r6, r7}	)
  THUMB(	ldr	sp, [r3, #16]		)
arch/arm/kernel/head.S +0 -0
index 591a2ea..be64264 100644

arch/arm/kernel/head.S line 82

Quoted 8 lines
arch/arm/kernel/head.S +5 -0
@@ -75,6 +75,11 @@
 ENTRY(stext)
 	setmode	PSR_F_BIT | PSR_I_BIT | SVC_MODE, r9 @ ensure svc mode
 						@ and irqs disabled
+
+#if defined(CONFIG_DEBUG_LL) && !defined(CONFIG_DEBUG_ICEDCC)
+	inituart r1, r3, r4
+#endif
+

Here you have two calls, one which is performed when the MMU is off, and the other one (after .bss is cleared) when the MMU is on. Did you consider the implications of accessing that .bss variable in those two circumstances? This is also true for when printascii is called.

Ensuring that .data is used instead of .bss would eliminate one of those calls which is a good thing to do. But extra cleverness is needed to retrieve the config data in a position independent way.

Nicolas

#3 lore raw

PATCH 1/2 ARM: Add inituart macro to initialize DEBUG_LL serial port based on the machine ID

In reply to Tony Lindgren
Quoted 11 lines · Tony Lindgren

Allow machine specific init of the DEBUG_LL serial port. This is needed to debug kernels built with support for multiple machines compiled in without recompiling the kernel.

As some SoCs need to use variables to store the port address and LSR register configuration, we must call inituart again after clearing the BSS.

If variables are being used for for inituart and addruart, this setup won't work properly for debugging the uncompress code without patching arch/arm/boot/compressed/head.S for the machine in question.

Can't we just hard-configure the virtual/physical address at build time and be done with it?

I've given up with the current state of affairs which tries to use the platform ID to select the UART to use as it never seems to work, and I have a couple of patches which hard-code the address at compile time - one for the SDP4430 board and one for the LDP3430 board.

If it's complicated, then it probably won't work. Keep it simple. That's especially true for debugging code, otherwise you need extra debugging code to debug why the debugging code doesn't work.

#4 lore raw

PATCH 1/2 ARM: Add inituart macro to initialize DEBUG_LL serial port based on the machine ID

Quoted 11 lines · Russell King - ARM Linux

Can't we just hard-configure the virtual/physical address at build time and be done with it?

I've given up with the current state of affairs which tries to use the platform ID to select the UART to use as it never seems to work, and I have a couple of patches which hard-code the address at compile time - one for the SDP4430 board and one for the LDP3430 board.

If it's complicated, then it probably won't work. Keep it simple. That's especially true for debugging code, otherwise you need extra debugging code to debug why the debugging code doesn't work.

There's another good reason to hard-configure the UART port rather than select it by ID.

The common usage scenario: you're bringing up a new board. You know you're going to have your console connected to UART2. So, no matter what you want your debug messages to come out of UART2 even if the machine ID is wrong.

By detecting the UART port from the machine number, you immediately lose that ability, and therefore the confidence, that "if I build the kernel for X with LL debug enabled, and monitor port Y, I will get messages out of port Y, and not some other random port Z which I'd to solder wires to to monitor."

In other words, no messages on the monitored port changes from "we didn't get into the kernel, or something early in the kernel boot before the C code went wrong" to "... or maybe the debugging code failed to get the right port too."

It is invaluable to know that the debugging code will always talk to the same UART which you're monitoring.

author maintainer
#5 lore raw

PATCH 1/2 ARM: Add inituart macro to initialize DEBUG_LL serial port based on the machine ID

Quoted 13 lines · Russell King - ARM Linux
Quoted 11 lines · Russell King - ARM Linux

Can't we just hard-configure the virtual/physical address at build time and be done with it?

I've given up with the current state of affairs which tries to use the platform ID to select the UART to use as it never seems to work, and I have a couple of patches which hard-code the address at compile time - one for the SDP4430 board and one for the LDP3430 board.

If it's complicated, then it probably won't work. Keep it simple. That's especially true for debugging code, otherwise you need extra debugging code to debug why the debugging code doesn't work.

Quoted 7 lines

There's another good reason to hard-configure the UART port rather than select it by ID.

The common usage scenario: you're bringing up a new board. You know you're going to have your console connected to UART2. So, no matter what you want your debug messages to come out of UART2 even if the machine ID is wrong.

Yes that's an important debugging case too. Another common use case is "this kernel boots on machines a and b, but fails to boot on c and d".

Quoted 5 lines

By detecting the UART port from the machine number, you immediately lose that ability, and therefore the confidence, that "if I build the kernel for X with LL debug enabled, and monitor port Y, I will get messages out of port Y, and not some other random port Z which I'd to solder wires to to monitor."

True, but that easily also leads to confusion on why some kernel only boots on one machine. So maybe we can do something that can easily be selected in Kconfig for forcing certain port?

Quoted 7 lines

In other words, no messages on the monitored port changes from "we didn't get into the kernel, or something early in the kernel boot before the C code went wrong" to "... or maybe the debugging code failed to get the right port too."

It is invaluable to know that the debugging code will always talk to the same UART which you're monitoring.

I'll take a look how we can allow forcing the uart easily.

Regards,

Tony

author maintainer
#6 lore raw

PATCH 2/2 ARM: Add empty inituart macros

In reply to Tony Lindgren

Add empty inituart macros. These can be used to initialize the debug serial port based on the machine ID.

Signed-off-by Tony Lindgren <[email protected]>
---
 arch/arm/mach-aaec2000/include/mach/debug-macro.S  |    4 ++++
 arch/arm/mach-at91/include/mach/debug-macro.S      |    3 +++
 arch/arm/mach-clps711x/include/mach/debug-macro.S  |    3 +++
 arch/arm/mach-cns3xxx/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-davinci/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-dove/include/mach/debug-macro.S      |    3 +++
 arch/arm/mach-ebsa110/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-ep93xx/include/mach/debug-macro.S    |    3 +++
 .../arm/mach-footbridge/include/mach/debug-macro.S |    4 ++++
 arch/arm/mach-gemini/include/mach/debug-macro.S    |    3 +++
 .../arm/mach-integrator/include/mach/debug-macro.S |    3 +++
 arch/arm/mach-iop13xx/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-iop32x/include/mach/debug-macro.S    |    3 +++
 arch/arm/mach-iop33x/include/mach/debug-macro.S    |    3 +++
 arch/arm/mach-ixp23xx/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-kirkwood/include/mach/debug-macro.S  |    3 +++
 arch/arm/mach-ks8695/include/mach/debug-macro.S    |    3 +++
 arch/arm/mach-l7200/include/mach/debug-macro.S     |    3 +++
 arch/arm/mach-loki/include/mach/debug-macro.S      |    3 +++
 arch/arm/mach-lpc32xx/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-mmp/include/mach/debug-macro.S       |    3 +++
 arch/arm/mach-msm/include/mach/debug-macro.S       |    4 ++++
 arch/arm/mach-mv78xx0/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-mxs/include/mach/debug-macro.S       |    3 +++
 arch/arm/mach-netx/include/mach/debug-macro.S      |    3 +++
 arch/arm/mach-nomadik/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-ns9xxx/include/mach/debug-macro.S    |    3 +++
 arch/arm/mach-omap1/include/mach/debug-macro.S     |    3 +++
 arch/arm/mach-omap2/include/mach/debug-macro.S     |    3 +++
 arch/arm/mach-pnx4008/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-pxa/include/mach/debug-macro.S       |    3 +++
 arch/arm/mach-realview/include/mach/debug-macro.S  |    3 +++
 arch/arm/mach-rpc/include/mach/debug-macro.S       |    3 +++
 arch/arm/mach-s3c2410/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-s3c24a0/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-s3c64xx/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-s5p6442/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-s5p64x0/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-s5pc100/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-s5pv210/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-s5pv310/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-sa1100/include/mach/debug-macro.S    |    3 +++
 arch/arm/mach-shark/include/mach/debug-macro.S     |    3 +++
 arch/arm/mach-u300/include/mach/debug-macro.S      |    3 +++
 arch/arm/mach-ux500/include/mach/debug-macro.S     |    3 +++
 arch/arm/mach-versatile/include/mach/debug-macro.S |    3 +++
 arch/arm/mach-vexpress/include/mach/debug-macro.S  |    3 +++
 arch/arm/plat-mxc/include/mach/debug-macro.S       |    3 +++
 arch/arm/plat-spear/include/plat/debug-macro.S     |    3 +++
 arch/arm/plat-stmp3xxx/include/mach/debug-macro.S  |    3 +++
 arch/arm/plat-tcc/include/mach/debug-macro.S       |    3 +++
 51 files changed, 156 insertions(+), 0 deletions(-)
arch/arm/mach-aaec2000/include/mach/debug-macro.S +4 -0
index bc7ad55..1a15ebb 100644
@@ -10,6 +10,10 @@
  */
 
 #include "hardware.h"
+
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		mov	\rp, 0x00000800
 		orr	\rv, \rp, #io_p2v(0x80000000)	@ virtual
arch/arm/mach-at91/include/mach/debug-macro.S +3 -0
index 0f959fa..d752c57 100644
@@ -14,6 +14,9 @@
 #include <mach/hardware.h>
 #include <mach/at91_dbgu.h>
 
+	.macro	inituart, id, a, v
+	.endm
+
 	.macro	addruart, rp, rv
 	ldr	\rp, =(AT91_BASE_SYS + AT91_DBGU)		@ System peripherals (phys address)
 	ldr	\rv, =(AT91_VA_BASE_SYS	+ AT91_DBGU)		@ System peripherals (virt address)
arch/arm/mach-clps711x/include/mach/debug-macro.S +3 -0
index 507c687..f029a4e 100644
@@ -14,6 +14,9 @@
 #include <mach/hardware.h>
 #include <asm/hardware/clps7111.h>
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 #ifndef CONFIG_DEBUG_CLPS711X_UART2
 		mov	\rp, #0x0000	@ UART1
arch/arm/mach-cns3xxx/include/mach/debug-macro.S +3 -0
index 56d8286..eb01d86 100644
@@ -10,6 +10,9 @@
  * published by the Free Software Foundation.
  */
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart,rp,rv
 		mov	\rp, #0x00009000
 		orr	\rv, \rp, #0xf0000000	@ virtual base
arch/arm/mach-davinci/include/mach/debug-macro.S +3 -0
index 9f1befc..00af9bb 100644
@@ -29,6 +29,9 @@ davinci_uart_phys:	.word	0
 davinci_uart_virt:	.word	0
 		.popsection
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro addruart, rp, rv
 
 		/* Use davinci_uart_phys/virt if already configured */
arch/arm/mach-dove/include/mach/debug-macro.S +3 -0
index da8bf2b..3c60a90 100644
@@ -8,6 +8,9 @@
 
 #include <mach/bridge-regs.h>
 
+	.macro	inituart, id, a, v
+	.endm
+
 	.macro	addruart, rp, rv
 	ldr	\rp, =DOVE_SB_REGS_PHYS_BASE
 	ldr	\rv, =DOVE_SB_REGS_VIRT_BASE
arch/arm/mach-ebsa110/include/mach/debug-macro.S +3 -0
index 7ef5690..287178c 100644
@@ -11,6 +11,9 @@
  *
 **/
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		mov	\rp, #0xf0000000
 		orr	\rp, \rp, #0x00000be0
arch/arm/mach-ep93xx/include/mach/debug-macro.S +3 -0
index b25bc907..e840a96 100644
@@ -11,6 +11,9 @@
  */
 #include <mach/ep93xx-regs.h>
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		ldr	\rp, =EP93XX_APB_PHYS_BASE	@ Physical base
 		ldr	\rv, =EP93XX_APB_VIRT_BASE	@ virtual base
arch/arm/mach-footbridge/include/mach/debug-macro.S +4 -0
index 30b971d..30d6244 100644
@@ -15,6 +15,10 @@
 
 #ifndef CONFIG_DEBUG_DC21285_PORT
 	/* For NetWinder debugging */
+
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		mov	\rp, #0x000003f8
 		orr	\rv, \rp, #0xff000000	@ virtual
arch/arm/mach-gemini/include/mach/debug-macro.S +3 -0
index f40e006..0fe48bc 100644
@@ -11,6 +11,9 @@
  */
 #include <mach/hardware.h>
 
+	.macro	inituart, id, a, v
+	.endm
+
 	.macro	addruart, rp, rv
 	ldr	\rp, =GEMINI_UART_BASE			@ physical
 	ldr	\rv, =IO_ADDRESS(GEMINI_UART_BASE)	@ virtual
arch/arm/mach-integrator/include/mach/debug-macro.S +3 -0
index a1f598f..06681fe 100644
@@ -11,6 +11,9 @@
  *
 */
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		mov	\rp, #0x16000000	@ physical base address
 		mov	\rv, #0xf0000000	@ virtual base
arch/arm/mach-iop13xx/include/mach/debug-macro.S +3 -0
index e664466..685cb18 100644
@@ -11,6 +11,9 @@
  * published by the Free Software Foundation.
  */
 
+	.macro	inituart, id, a, v
+	.endm
+
 	.macro	addruart, rp, rv
 	mov	\rp, #0x00002300
 	orr	\rp, \rp, #0x00000040
arch/arm/mach-iop32x/include/mach/debug-macro.S +3 -0
index ff9e76c..7e6328a 100644
@@ -11,6 +11,9 @@
  * published by the Free Software Foundation.
  */
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		mov	\rp, #0xfe000000	@ physical as well as virtual
 		orr	\rp, \rp, #0x00800000	@ location of the UART
arch/arm/mach-iop33x/include/mach/debug-macro.S +3 -0
index 40c500d..601d688 100644
@@ -11,6 +11,9 @@
  * published by the Free Software Foundation.
  */
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		mov	\rp, #0x00ff0000
 		orr	\rp, \rp, #0x0000f700
arch/arm/mach-ixp23xx/include/mach/debug-macro.S +3 -0
index f7c6eef..813ff68 100644
@@ -12,6 +12,9 @@
  */
 #include <mach/ixp23xx.h>
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		ldr	\rp, =IXP23XX_PERIPHERAL_PHYS 	@ physical
 		ldr	\rv, =IXP23XX_PERIPHERAL_VIRT	@ virtual
arch/arm/mach-kirkwood/include/mach/debug-macro.S +3 -0
index db06ae4..4a7a9e6 100644
@@ -8,6 +8,9 @@
 
 #include <mach/bridge-regs.h>
 
+	.macro	inituart, id, a, v
+	.endm
+
 	.macro	addruart, rp, rv
 	ldr	\rp, =KIRKWOOD_REGS_PHYS_BASE
 	ldr	\rv, =KIRKWOOD_REGS_VIRT_BASE
arch/arm/mach-ks8695/include/mach/debug-macro.S +3 -0
index bf516ad..07f346b 100644
@@ -14,6 +14,9 @@
 #include <mach/hardware.h>
 #include <mach/regs-uart.h>
 
+	.macro	inituart, id, a, v
+	.endm
+
 	.macro	addruart, rp, rv
 		ldr	\rp, =KS8695_UART_PA		@ physical base address
 		ldr	\rv, =KS8695_UART_VA		@ virtual base address
arch/arm/mach-l7200/include/mach/debug-macro.S +3 -0
index b0a2db7..a637598 100644
@@ -14,6 +14,9 @@
 		.equ	io_virt, IO_BASE
 		.equ	io_phys, IO_START
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		mov	\rp, #0x00044000	@ UART1
 @		mov	\rp, #0x00045000	@ UART2
arch/arm/mach-loki/include/mach/debug-macro.S +3 -0
index cc90d99..580d939 100644
@@ -8,6 +8,9 @@
 
 #include <mach/loki.h>
 
+	.macro	inituart, id, a, v
+	.endm
+
 	.macro	addruart, rp, rv
 	ldr	\rp, =LOKI_REGS_PHYS_BASE
 	ldr	\rv, =LOKI_REGS_VIRT_BASE
arch/arm/mach-lpc32xx/include/mach/debug-macro.S +3 -0
index 629e744..9b51e20 100644
@@ -20,6 +20,9 @@
  * Debug output is hardcoded to standard UART 5
 */
 
+	.macro	inituart, id, a, v
+	.endm
+
 	.macro	addruart, rp, rv
 	ldreq	\rp, =0x40090000
 	ldrne	\rv, =0xF4090000
arch/arm/mach-mmp/include/mach/debug-macro.S +3 -0
index 7e2ebd3..c7c579a 100644
@@ -11,6 +11,9 @@
 
 #include <mach/addr-map.h>
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		ldr	\rp, =APB_PHYS_BASE		@ physical
 		ldr	\rv, =APB_VIRT_BASE		@ virtual
arch/arm/mach-msm/include/mach/debug-macro.S +4 -0
index 646b99e..8d574ec 100644
@@ -20,6 +20,10 @@
 #include <mach/msm_iomap.h>
 
 #if defined(CONFIG_HAS_MSM_DEBUG_UART_PHYS) && !defined(CONFIG_MSM_DEBUG_UART_NONE)
+
+	.macro	inituart, id, a, v
+	.endm
+
 	.macro	addruart, rp, rv
 	ldr	\rp, =MSM_DEBUG_UART_PHYS
 	ldr	\rv, =MSM_DEBUG_UART_BASE
arch/arm/mach-mv78xx0/include/mach/debug-macro.S +3 -0
index 0489142..31dd8d0 100644
@@ -8,6 +8,9 @@
 
 #include <mach/mv78xx0.h>
 
+	.macro	inituart, id, a, v
+	.endm
+
 	.macro	addruart, rp, rv
 	ldr	\rp, =MV78XX0_REGS_PHYS_BASE
 	ldr	\rv, =MV78XX0_REGS_VIRT_BASE
arch/arm/mach-mxs/include/mach/debug-macro.S +3 -0
index 79650a1..f2ca06b 100644
@@ -30,6 +30,9 @@
 
 #define UART_VADDR	MXS_IO_ADDRESS(UART_PADDR)
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		ldr	\rp, =UART_PADDR	@ physical
 		ldr	\rv, =UART_VADDR	@ virtual
arch/arm/mach-netx/include/mach/debug-macro.S +3 -0
index 56a9152..6edba149 100644
@@ -13,6 +13,9 @@
 
 #include "hardware.h"
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		mov	\rp, #0x00000a00
 		orr	\rv, \rp, #io_p2v(0x00100000)	@ virtual
arch/arm/mach-nomadik/include/mach/debug-macro.S +3 -0
index e7151b4..ea3baf0 100644
@@ -10,6 +10,9 @@
  *
 */
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		mov	\rp, #0x00100000
 		add	\rp, \rp, #0x000fb000
arch/arm/mach-ns9xxx/include/mach/debug-macro.S +3 -0
index 5a2acbd..d5c0d4b 100644
@@ -12,6 +12,9 @@
 
 #include <mach/regs-board-a9m9750dev.h>
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		ldr	\rp, =NS9XXX_CSxSTAT_PHYS(0)
 		ldr	\rv, =io_p2v(NS9XXX_CSxSTAT_PHYS(0))
arch/arm/mach-omap1/include/mach/debug-macro.S +3 -0
index 6285604..bf0cc57 100644
@@ -25,6 +25,9 @@ omap_uart_phys:	.word	0x0
 omap_uart_virt:	.word	0x0
 		.popsection
 
+		.macro	inituart, id, a, v
+		.endm
+
 		/*
 		 * Note that this code won't work if the bootloader passes
 		 * a wrong machine ID number in r1. To debug, just hardcode
arch/arm/mach-omap2/include/mach/debug-macro.S +3 -0
index 6049f46..6bbe2dd 100644
@@ -28,6 +28,9 @@ omap_uart_virt:	.word	0
 omap_uart_lsr:	.word	0
 		.popsection
 
+		.macro	inituart, id, a, v
+		.endm
+
 		/*
 		 * Note that this code won't work if the bootloader passes
 		 * a wrong machine ID number in r1. To debug, just hardcode
arch/arm/mach-pnx4008/include/mach/debug-macro.S +3 -0
index 931afeb..a1f4dc8 100644
@@ -11,6 +11,9 @@
  *
 */
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		mov	\rp, #0x00090000
 		add	\rv, \rp, #0xf4000000	@ virtual
arch/arm/mach-pxa/include/mach/debug-macro.S +3 -0
index 7d5c751..bc9a505 100644
@@ -13,6 +13,9 @@
 
 #include "hardware.h"
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		mov	\rp, #0x00100000
 		orr	\rv, \rp, #io_p2v(0x40000000)	@ virtual
arch/arm/mach-realview/include/mach/debug-macro.S +3 -0
index 90b687c..89b106c 100644
@@ -33,6 +33,9 @@
 #error "Unknown RealView platform"
 #endif
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		mov	\rp, #DEBUG_LL_UART_OFFSET
 		orr	\rv, \rp, #0xfb000000	@ virtual base
arch/arm/mach-rpc/include/mach/debug-macro.S +3 -0
index 85effff..f65806d 100644
@@ -11,6 +11,9 @@
  *
 */
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		mov	\rp, #0x00010000
 		orr	\rp, \rp, #0x00000fe0
arch/arm/mach-s3c2410/include/mach/debug-macro.S +3 -0
index 5882dea..d6d8b91 100644
@@ -19,6 +19,9 @@
 #define S3C2410_UART1_OFF (0x4000)
 #define SHIFT_2440TXF (14-9)
 
+	.macro	inituart, id, a, v
+	.endm
+
 	.macro addruart, rp, rv
 		ldr	\rp, = S3C24XX_PA_UART
 		ldr	\rv, = S3C24XX_VA_UART
arch/arm/mach-s3c24a0/include/mach/debug-macro.S +3 -0
index 0c5a738..3f0d15d 100644
@@ -10,6 +10,9 @@
 #include <mach/map.h>
 #include <plat/regs-serial.h>
 
+	.macro	inituart, id, a, v
+	.endm
+
 	.macro addruart, rp, rv
 		ldr	\rp, = S3C24XX_PA_UART
 		ldr	\rv, = S3C24XX_VA_UART
arch/arm/mach-s3c64xx/include/mach/debug-macro.S +3 -0
index a29e705..8510711 100644
@@ -21,6 +21,9 @@
 	 * aligned and add in the offset when we load the value here.
 	 */
 
+	.macro	inituart, id, a, v
+	.endm
+
 	.macro addruart, rp, rv
 		ldr	\rp, = S3C_PA_UART
 		ldr	\rv, = (S3C_VA_UART + S3C_PA_UART & 0xfffff)
arch/arm/mach-s5p6442/include/mach/debug-macro.S +3 -0
index e221320..822e075 100644
@@ -15,6 +15,9 @@
 #include <mach/map.h>
 #include <plat/regs-serial.h>
 
+	.macro	inituart, id, a, v
+	.endm
+
 	.macro addruart, rp, rv
 		ldr	\rp, = S3C_PA_UART
 		ldr	\rv, = S3C_VA_UART
arch/arm/mach-s5p64x0/include/mach/debug-macro.S +3 -0
index 79b04e6..814f0c9 100644
@@ -15,6 +15,9 @@
 
 #include <plat/regs-serial.h>
 
+	.macro	inituart, id, a, v
+	.endm
+
 	.macro addruart, rp, rv
 		mov	\rp, #0xE0000000
 		orr	\rp, \rp, #0x00100000
arch/arm/mach-s5pc100/include/mach/debug-macro.S +3 -0
index b2ba95d..8371e60 100644
@@ -22,6 +22,9 @@
 	 * aligned and add in the offset when we load the value here.
 	 */
 
+	.macro	inituart, id, a, v
+	.endm
+
 	.macro addruart, rp, rv
 		ldr	\rp, = S3C_PA_UART
 		ldr	\rv, = S3C_VA_UART
arch/arm/mach-s5pv210/include/mach/debug-macro.S +3 -0
index 169fe65..e5a3269 100644
@@ -21,6 +21,9 @@
 	 * aligned and add in the offset when we load the value here.
 	 */
 
+	.macro	inituart, id, a, v
+	.endm
+
 	.macro addruart, rp, rv
 		ldr	\rp, = S3C_PA_UART
 		ldr	\rv, = S3C_VA_UART
arch/arm/mach-s5pv310/include/mach/debug-macro.S +3 -0
index b0d920c..9e85890 100644
@@ -20,6 +20,9 @@
 	 * aligned and add in the offset when we load the value here.
 	 */
 
+	.macro	inituart, id, a, v
+	.endm
+
 	.macro addruart, rp, rv
 		ldreq	\rp, = S3C_PA_UART
 		ldrne	\rv, = S3C_VA_UART
arch/arm/mach-sa1100/include/mach/debug-macro.S +3 -0
index 0cd0fc9..5ae99eb 100644
@@ -12,6 +12,9 @@
 */
 #include <mach/hardware.h>
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		mrc	p15, 0, \rp, c1, c0
 		tst	\rp, #1			@ MMU enabled?
arch/arm/mach-shark/include/mach/debug-macro.S +3 -0
index a473f55..804fcee 100644
@@ -11,6 +11,9 @@
  *
 */
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		mov	\rp, #0xe0000000
 		orr	\rp, \rp, #0x000003f8
arch/arm/mach-u300/include/mach/debug-macro.S +3 -0
index df71570..d478038 100644
@@ -10,6 +10,9 @@
  */
 #include <mach/hardware.h>
 
+	.macro	inituart, id, a, v
+	.endm
+
 	.macro	addruart, rp, rv
 	/* If we move the address using MMU, use this. */
 	ldr	\rp,	  = U300_SLOW_PER_PHYS_BASE @ MMU off, physical address
arch/arm/mach-ux500/include/mach/debug-macro.S +3 -0
index 700fb05..fe49836 100644
@@ -35,6 +35,9 @@
 #define UX500_UART(n)	__UX500_UART(n)
 #define UART_BASE	UX500_UART(CONFIG_UX500_DEBUG_UART)
 
+	.macro	inituart, id, a, v
+	.endm
+
 	.macro	addruart, rp, rv
 	ldr	\rp, =UART_BASE				@ no, physical address
 	ldr	\rv, =IO_ADDRESS(UART_BASE)		@ yes, virtual address
arch/arm/mach-versatile/include/mach/debug-macro.S +3 -0
index eb2cf7d..09e6d37 100644
@@ -11,6 +11,9 @@
  *
 */
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		mov	\rp,      #0x001F0000
 		orr	\rp, \rp, #0x00001000
arch/arm/mach-vexpress/include/mach/debug-macro.S +3 -0
index 050d65e..e4f982e 100644
@@ -12,6 +12,9 @@
 
 #define DEBUG_LL_UART_OFFSET	0x00009000
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart,rp,rv
 		mov	\rp, #DEBUG_LL_UART_OFFSET
 		orr	\rv, \rp, #0xf8000000	@ virtual base
arch/arm/plat-mxc/include/mach/debug-macro.S +3 -0
index 3b3a37c..8c7d0c6 100644
@@ -53,6 +53,9 @@
 
 #define UART_VADDR	IMX_IO_ADDRESS(UART_PADDR)
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		ldr	\rp, =UART_PADDR	@ physical
 		ldr	\rv, =UART_VADDR	@ virtual
arch/arm/plat-spear/include/plat/debug-macro.S +3 -0
index e91270e..5594e29 100644
@@ -14,6 +14,9 @@
 #include <linux/amba/serial.h>
 #include <mach/spear.h>
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		mov	\rp, #SPEAR_DBG_UART_BASE		@ Physical base
 		mov	\rv, #VA_SPEAR_DBG_UART_BASE		@ Virtual base
arch/arm/plat-stmp3xxx/include/mach/debug-macro.S +3 -0
index d3a0985..2e0652e 100644
@@ -16,6 +16,9 @@
  * http://www.gnu.org/copyleft/gpl.html
  */
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		mov	\rp,      #0x00070000
 		add	\rv, \rp, #0xf0000000	@ virtual base
arch/arm/plat-tcc/include/mach/debug-macro.S +3 -0
index 7662f73..629901c 100644
@@ -9,6 +9,9 @@
  *
  */
 
+		.macro	inituart, id, a, v
+		.endm
+
 		.macro	addruart, rp, rv
 		moveq	\rp, #0x90000000	@ physical base address
 		movne	\rv, #0xF1000000	@ virtual base
#7 lore raw

PATCH 2/2 ARM: Add empty inituart macros

Quoted 49 lines · Tony Lindgren

Add empty inituart macros. These can be used to initialize the debug serial port based on the machine ID.

Signed-off-by Tony Lindgren <[email protected]>
---
 arch/arm/mach-aaec2000/include/mach/debug-macro.S  |    4 ++++
 arch/arm/mach-at91/include/mach/debug-macro.S      |    3 +++
 arch/arm/mach-clps711x/include/mach/debug-macro.S  |    3 +++
 arch/arm/mach-cns3xxx/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-davinci/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-dove/include/mach/debug-macro.S      |    3 +++
 arch/arm/mach-ebsa110/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-ep93xx/include/mach/debug-macro.S    |    3 +++
 .../arm/mach-footbridge/include/mach/debug-macro.S |    4 ++++
 arch/arm/mach-gemini/include/mach/debug-macro.S    |    3 +++
 .../arm/mach-integrator/include/mach/debug-macro.S |    3 +++
 arch/arm/mach-iop13xx/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-iop32x/include/mach/debug-macro.S    |    3 +++
 arch/arm/mach-iop33x/include/mach/debug-macro.S    |    3 +++
 arch/arm/mach-ixp23xx/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-kirkwood/include/mach/debug-macro.S  |    3 +++
 arch/arm/mach-ks8695/include/mach/debug-macro.S    |    3 +++
 arch/arm/mach-l7200/include/mach/debug-macro.S     |    3 +++
 arch/arm/mach-loki/include/mach/debug-macro.S      |    3 +++
 arch/arm/mach-lpc32xx/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-mmp/include/mach/debug-macro.S       |    3 +++
 arch/arm/mach-msm/include/mach/debug-macro.S       |    4 ++++
 arch/arm/mach-mv78xx0/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-mxs/include/mach/debug-macro.S       |    3 +++
 arch/arm/mach-netx/include/mach/debug-macro.S      |    3 +++
 arch/arm/mach-nomadik/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-ns9xxx/include/mach/debug-macro.S    |    3 +++
 arch/arm/mach-omap1/include/mach/debug-macro.S     |    3 +++
 arch/arm/mach-omap2/include/mach/debug-macro.S     |    3 +++
 arch/arm/mach-pnx4008/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-pxa/include/mach/debug-macro.S       |    3 +++
 arch/arm/mach-realview/include/mach/debug-macro.S  |    3 +++
 arch/arm/mach-rpc/include/mach/debug-macro.S       |    3 +++
 arch/arm/mach-s3c2410/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-s3c24a0/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-s3c64xx/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-s5p6442/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-s5p64x0/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-s5pc100/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-s5pv210/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-s5pv310/include/mach/debug-macro.S   |    3 +++
 arch/arm/mach-sa1100/include/mach/debug-macro.S    |    3 +++
 arch/arm/mach-shark/include/mach/debug-macro.S     |    3 +++
 arch/arm/mach-u300/include/mach/debug-macro.S      |    3 +++
Quoted 8 lines
 arch/arm/mach-ux500/include/mach/debug-macro.S     |    3 +++
 arch/arm/mach-versatile/include/mach/debug-macro.S |    3 +++
 arch/arm/mach-vexpress/include/mach/debug-macro.S  |    3 +++
 arch/arm/plat-mxc/include/mach/debug-macro.S       |    3 +++
 arch/arm/plat-spear/include/plat/debug-macro.S     |    3 +++
 arch/arm/plat-stmp3xxx/include/mach/debug-macro.S  |    3 +++
 arch/arm/plat-tcc/include/mach/debug-macro.S       |    3 +++
 51 files changed, 156 insertions(+), 0 deletions(-)

A better way would be to define the empty inituart macro in a common place, and use the following in the machine specific header file:

	.purgem inituart
	.macro inituart ...
	...
	.endm

This way you won't need to add empty inituart all over the place.

Nicolas

author maintainer
#8 lore raw

PATCH 2/2 ARM: Add empty inituart macros

Quoted 4 lines · Nicolas Pitre
Quoted 2 lines · Tony Lindgren

Add empty inituart macros. These can be used to initialize the debug serial port based on the machine ID.

...

Quoted 9 lines

A better way would be to define the empty inituart macro in a common place, and use the following in the machine specific header file:

	.purgem inituart
	.macro inituart ...
	...
	.endm

This way you won't need to add empty inituart all over the place.

Thanks for the tip, will try that out.

Tony

#9 lore raw

cover Allow using machine ID for DEBUG_LL macros

In reply to Tony Lindgren
Quoted 4 lines · Tony Lindgren

Hi all,

Here are two patches that allow using machine ID for DEBUG_LL macros by adding a new macro inituart.

This won't work with the device tree support as the machine ID is then replaced with a catch-it-all-with-dt-support machine ID.

Nicolas

author maintainer
#10 lore raw

cover Allow using machine ID for DEBUG_LL macros

Quoted 9 lines · Nicolas Pitre
Quoted 4 lines · Tony Lindgren

Hi all,

Here are two patches that allow using machine ID for DEBUG_LL macros by adding a new macro inituart.

This won't work with the device tree support as the machine ID is then replaced with a catch-it-all-with-dt-support machine ID.

Hmm, maybe for device tree we could only have it initialized later on by setting up custom early_printk in early_printk.c based on the device tree data or machine ID?

It won't work very early then though.. If we want it to work early we could allocate some fixed memory chunk for addruart etc functions for which the bootloader just passes addresses.

Tony

#11 lore raw

cover Allow using machine ID for DEBUG_LL macros

Quoted 11 lines · Tony Lindgren
Quoted 9 lines · Nicolas Pitre
Quoted 4 lines · Tony Lindgren

Hi all,

Here are two patches that allow using machine ID for DEBUG_LL macros by adding a new macro inituart.

This won't work with the device tree support as the machine ID is then replaced with a catch-it-all-with-dt-support machine ID.

Quoted 7 lines

Hmm, maybe for device tree we could only have it initialized later on by setting up custom early_printk in early_printk.c based on the device tree data or machine ID?

It won't work very early then though.. If we want it to work early we could allocate some fixed memory chunk for addruart etc functions for which the bootloader just passes addresses.

Nah... Let's keep relationship between the kernel and bootloaders to a strict minimum. If necessary we'll find a way to extract that info from the dtb in assembly. I'd suggest just continuing this excellent cleanup for the time being.

Nicolas