No output from SMC1 console with the 2.6.26 kernel (PQ2FADS based board)

No output from SMC1 console with the 2.6.26 kernel (PQ2FADS based board)

[Matvejchikov Ilya]

Hi all,

I'm working with PQ2FADS based board. When I started to use new 2.6.26
kernel my SMC1 console stopped working. I know that the cpm_uart
driver has been changed and the DTS file needs updating. Unfortunately
I failed to get it running. Could somebody help me solve this problem?

====
The cpm node of the DTS file:
.............................................
		cpm@119c0 {
			#address-cells = <1>;
			#size-cells = <1>;
			#interrupt-cells = <2>;
			compatible = "fsl,mpc8280-cpm", "fsl,cpm2";
			reg = <119c0 30>;
			ranges;

			muram {
				#address-cells = <1>;
				#size-cells = <1>;
				ranges = <0 0 10000>;

				data-only@0 {
					compatible = "fsl,cpm-muram-data";
					reg = <0 2000 9800 800>;
				};
			};

			brg@119f0 {
				compatible = "fsl,cpm-brg", "fsl,cpm2-brg";
				reg = <119f0 10 115f0 10>;
			};

			smc1: serial@11a80 {
				device_type = "serial";
				compatible = "fsl,cpm2-smc-uart";
				reg = <11a80 20 87fc 2>;
				interrupts = <4 8>;
				interrupt-parent = <&PIC>;
				fsl,cpm-brg = <7>;
				fsl,cpm-command = <1d000000>;
			};

		};
.............................................
	chosen {
		linux,stdout-path = &smc1;
		bootargs = "console=ttyCPM0";
	};
.............................................

The early debuging output:
Xid mach(): done
MMU:enter
MMU:hw init
MMU:mapin
MMU:setio
MMU:exit
Using Electronic Devices SPC826 (M82) machine description
Linux version 2.6.26 (ilya@westend) (gcc version 4.1.2) #83 Thu Jul 24
14:45:07 MSD 2008
console [udbg0] enabled
Entering add_active_range(0, 0, 4096) 0 entries of 256 used
setup_arch: bootmem
spc826_setup_arch()
spc826_setup_arch(), finish
arch: exit
Top of RAM: 0x1000000, Total RAM: 0x1000000
Memory hole size: 0MB
Zone PFN ranges:
  DMA             0 ->     4096
  Normal       4096 ->     4096
Movable zone start PFN for each node
early_node_map[1] active PFN ranges
    0:        0 ->     4096
On node 0 totalpages: 4096
  DMA zone: 32 pages used for memmap
  DMA zone: 0 pages reserved
  DMA zone: 4064 pages, LIFO batch:0
  Normal zone: 0 pages used for memmap
  Movable zone: 0 pages used for memmap
Built 1 zonelists in Zone order, mobility grouping off.  Total pages: 4064
Kernel command line: console=ttyCPM0
PID hash table entries: 64 (order: 6, 256 bytes)
time_init: decrementer frequency = 16.500000 MHz
time_init: processor frequency   = 264.000000 MHz
clocksource: timebase mult[f26c9b2] shift[22] registered
clockevent: decrementer mult[439] shift[16] cpu[0]
Console: colour dummy device 80x25
====

Thanks!

Re: No output from SMC1 console with the 2.6.26 kernel (PQ2FADS based board)

[Scott Wood]

Matvejchikov Ilya wrote:
> 		cpm@119c0 {
> 			#address-cells = <1>;
> 			#size-cells = <1>;
> 			#interrupt-cells = <2>;
> 			compatible = "fsl,mpc8280-cpm", "fsl,cpm2";

Add "simple-bus" to this compatible list.

Other than that, and that you should be using dts-v1, the tree looks 
fine.  If adding "simple-bus" doesn't fix it, check your pin setup; 
pq2fads doesn't have an SMC serial port, so its platform file doesn't 
set up those pins.

-Scott

Re: No output from SMC1 console with the 2.6.26 kernel (PQ2FADS based board)

[Matvejchikov Ilya]

No, it's not working for me :(

My pins is configured by u-boot so I disable init_ioports() function
call. Moreover the udbg0 console forks fine... I have no output at all
after "udbg_putc = NULL" line in the cpm_uart driver. As I see it the
cpm_uart driver doesn't run properly after udbg console has turned
off.....

2008/7/28 Scott Wood <scottwood@freescale.com>:
> Matvejchikov Ilya wrote:
>>
>>                cpm@119c0 {
>>                        #address-cells = <1>;
>>                        #size-cells = <1>;
>>                        #interrupt-cells = <2>;
>>                        compatible = "fsl,mpc8280-cpm", "fsl,cpm2";
>
> Add "simple-bus" to this compatible list.
>
> Other than that, and that you should be using dts-v1, the tree looks fine.
>  If adding "simple-bus" doesn't fix it, check your pin setup; pq2fads
> doesn't have an SMC serial port, so its platform file doesn't set up those
> pins.
>
> -Scott
>
>

No output from SMC1 console with the 2.6.26 kernel (8xx based board)

[Ben Gardiner]

In 'Re: No output from SMC1 console with the 2.6.26 kernel (PQ2FADS 
based    board)' Matvejchikov Ilya wrote:
> No, it's not working for me :(
>
> My pins is configured by u-boot so I disable init_ioports() function
> call. Moreover the udbg0 console forks fine... I have no output at all
> after "udbg_putc = NULL" line in the cpm_uart driver. As I see it the
> cpm_uart driver doesn't run properly after udbg console has turned
> off.....
>   
I think I'm having a similar problem with an 8xx based board.

I am calling cpm_reset() and cpm1_set_pin().
<snip nmx_setup.c>
...
static struct cpm_pin nmx_pins[] = {
    /* SMC1 */
    {CPM_PORTB, 24, CPM_PIN_INPUT}, /* RX */
    {CPM_PORTB, 25, CPM_PIN_INPUT | CPM_PIN_SECONDARY}, /* TX */
};

static void __init init_ioports(void)
{
    int i;

    for (i = 0; i < ARRAY_SIZE(nmx_pins); i++) {
        struct cpm_pin *pin = &nmx_pins[i];
        cpm1_set_pin(pin->port, pin->pin, pin->flags);
    }

    cpm1_clk_setup(CPM_CLK_SMC1, CPM_BRG1, CPM_CLK_RTX);

}

static void __init nmx_setup_arch(void)
{
    cpm_reset();
    init_ioports();
...
<snip>

I have a cpm dts entry copied from the mpc866ads.dts. I've also added 
the compatible = "simple-bus".
<snip nmx-taurus.dts>
...
        cpm@9c0 {
            #address-cells = <1>;
            #size-cells = <1>;
            compatible = "fsl,mpc866-cpm", "fsl,cpm1", "simple-bus";
            ranges;
            reg = <0x9c0 0x40>;
            brg-frequency = <0>;
            interrupts = <0 2>;    // cpm error interrupt
            interrupt-parent = <&CPM_PIC>;

            muram@2000 {
                #address-cells = <1>;
                #size-cells = <1>;
                ranges = <0x0 0x2000 0x2000>;

                data@0 {
                    compatible = "fsl,cpm-muram-data";
                    reg = <0x0 0x1c00>;
                };
            };

            brg@9f0 {
                compatible = "fsl,mpc866-brg",
                         "fsl,cpm1-brg",
                         "fsl,cpm-brg";
                reg = <0x9f0 0x10>;
                clock-frequency = <0>;
            };

            CPM_PIC: pic@930 {
                interrupt-controller;
                #address-cells = <0>;
                #interrupt-cells = <1>;
                interrupts = <5 2 0 2>;
                interrupt-parent = <&PIC>;
                reg = <0x930 0x20>;
                compatible = "fsl,mpc866-cpm-pic",
                             "fsl,cpm1-pic";
            };


            serial@a80 {
                device_type = "serial";
                compatible = "fsl,mpc866-smc-uart",
                             "fsl,cpm1-smc-uart";
                reg = <0xa80 0x10 0x3e80 0x40>;
                interrupts = <4>;
                interrupt-parent = <&CPM_PIC>;
                fsl,cpm-brg = <1>;
                fsl,cpm-command = <0x90>;
            };

            serial@a90 {
                device_type = "serial";
                compatible = "fsl,mpc866-smc-uart",
                             "fsl,cpm1-smc-uart";
                reg = <0xa90 0x10 0x3f80 0x40>;
                interrupts = <3>;
                interrupt-parent = <&CPM_PIC>;
                fsl,cpm-brg = <2>;
                fsl,cpm-command = <0xd0>;
            };

        };
    };
...
<snip>

I have CPM console SMC1 enabled
<snip .config>
CONFIG_SERIAL_CORE=y
CONFIG_SERIAL_CORE_CONSOLE=y
CONFIG_SERIAL_CPM=y
CONFIG_SERIAL_CPM_CONSOLE=y
CONFIG_SERIAL_CPM_SMC1=y
 <snip>

And my serial console output is stopping around the same point as 
Matvejchikov. I have baud 9600, so I'm guessing that it's cutoff because 
of this (please excuse me if this is wrong). NB: the console=ttyS0 
bootarg is there to get a working console when I  boot back to 2.4.
<snip console>
Memory <- <0x0 0x8000000> (128MB)
ENET0: local-mac-address <- 00:11:40:02:00:18
CPU clock-frequency <- 0x3f940aa (67MHz)
CPU timebase-frequency <- 0x1fce17 (2MHz)
CPU bus-frequency <- 0x1fce170 (33MHz)

zImage starting: loaded at 0x00400000 (sp: 0x07f77908)
Allocating 0x127c50 bytes for kernel ...
gunzipping (0x00000000 <- 0x0040c000:0x00538390)...done 0x11a680 bytes

Linux/PowerPC load: root=/dev/mtdblock2 rw panic=10 console=ttyCPM0 
console=ttyS0
Finalizing device tree... flat tree at 0x545300
Xid mach(): done
MMU:enter
MMU:hw init
MMU:mapin
MMU:setio
MMU:exit
Using NMX Taurus machine description
Linux version 2.6.26-dirty (BenGardiner@penguin.nanometrics.ca) (gcc 
version 4.0.1) #1 Tue Jul 2
9 10:43:11 EDT 2008
console [udbg0] enabled
Entering add_active_range(0, 0, 32768) 0 entries of 256 used
setup_arch: bootmem
arch: exit
Top of RAM: 0x8000000, Total RAM: 0x8000000
Memory hole size: 0MB
Zone PFN ranges:
  DMA             0 ->    32768
  Normal      32768 ->    32768
Movable zone start PFN for each node
early_node_map[1] active PFN ranges
    0:        0 ->    32768
On node 0 totalpages: 32768
  DMA zone: 256 pages used for memmap
  DMA zone: 0 pages reserved
  DMA zone: 32512 pages, LIFO batch:7
  Normal zone: 0 pages used for memmap
  Movable zone: 0 pages used for memmap
Built 1 zonelists in Zone order, mobility grouping on.  Total pages: 32512
Kernel command line: root=/dev/mtdblock2 rw panic=10 console=ttyCPM0 
console=ttyS0
PID hash table entries: 512 (order: 9, 2048 bytes)
Decrementer Frequency = 0x3f940a
time_init: decrementer frequency = 4.166666 MHz
time_init: processor frequency   = 66.666666 MHz
clocksource: timebase mult[3c0000a1] shift[22] registered
clockevent: decremente
<snip>

I've had the same behaviour with gcc 4.0.1 and gcc 4.3.0. Also with 
CONFIG_SERIAL_CPM_SCC1=y defined and not. Also with the smc2 dts entry 
removed and not. Also with ',9600' on the console=CPM0 bootarg and not.

Please excuse me for jumping in late. I hope this can help track down 
the problem.

,Ben

Re: No output from SMC1 console with the 2.6.26 kernel (8xx based board)

[Matvejchikov Ilya]

Hello Ben,

Have you tired to run 2.6.25 kernel? With 2.6.25.4 my console works
fine! I suspect there is something like a regression....

Ilya.

Re: No output from SMC1 console with the 2.6.26 kernel (8xx based board)

[Scott Wood]

On Tue, Jul 29, 2008 at 11:33:47AM -0400, Ben Gardiner wrote:
> And my serial console output is stopping around the same point as 
> Matvejchikov. I have baud 9600, so I'm guessing that it's cutoff because 
> of this (please excuse me if this is wrong). NB: the console=ttyS0 
> bootarg is there to get a working console when I  boot back to 2.4.
> <snip console>
> Memory <- <0x0 0x8000000> (128MB)
> ENET0: local-mac-address <- 00:11:40:02:00:18
> CPU clock-frequency <- 0x3f940aa (67MHz)
> CPU timebase-frequency <- 0x1fce17 (2MHz)
> CPU bus-frequency <- 0x1fce170 (33MHz)

Try commenting out calls to cpm_setbrg(), to see if the frequency is bad.

-Scott

Re: No output from SMC1 console with the 2.6.26 kernel (8xx based board)

[Scott Wood]

On Tue, Jul 29, 2008 at 10:36:30PM +0400, Matvejchikov Ilya wrote:
> Have you tired to run 2.6.25 kernel? With 2.6.25.4 my console works
> fine! I suspect there is something like a regression....

Did you use CONFIG_PPC_CPM_NEW_BINDING in 2.6.25?  It became mandatory in
2.6.26.  Also, try commenting out cpm_setbrg() calls in case the
frequency is not being set properly.

2.6.26 introduced the allocation of the CPM2 SMC parameter RAM area; what
did your device node look like in 2.6.25?  What happens if you use that
device tree with 2.6.26?

-Scott

Re: No output from SMC1 console with the 2.6.26 kernel (8xx based board)

[Matvejchikov Ilya]

> Did you use CONFIG_PPC_CPM_NEW_BINDING in 2.6.25?  It became mandatory in
> 2.6.26.  Also, try commenting out cpm_setbrg() calls in case the
> frequency is not being set properly.

Yes, this option was enabled. Nothing changed with empty cpm_setbrg()
function :(

> 2.6.26 introduced the allocation of the CPM2 SMC parameter RAM area; what
> did your device node look like in 2.6.25?  What happens if you use that
> device tree with 2.6.26?

The cpm node for the 2.6.25.4 kernel was the following:

		cpm@119c0 {
			#address-cells = <1>;
			#size-cells = <1>;
			#interrupt-cells = <2>;
			compatible = "fsl,mpc8280-cpm", "fsl,cpm2";
			reg = <119c0 30>;
			ranges;

			muram {
				#address-cells = <1>;
				#size-cells = <1>;
				ranges = <0 0 10000>;

				data-only@0 {
					compatible = "fsl,cpm-muram-data";
					reg = <100 1f00 9800 800>;
				};
			};

			brg@119f0 {
				compatible = "fsl,cpm-brg", "fsl,cpm2-brg";
				reg = <119f0 10 115f0 10>;
			};

			smc1: serial@11a80 {
				device_type = "serial";
				compatible = "fsl,cpm2-smc-uart";
				reg = <11a80 20 0 40>;
				interrupts = <4 8>;
				interrupt-parent = <&PIC>;
				fsl,cpm-brg = <7>;
				fsl,cpm-command = <1d000000>;
			};

		};

(muram node for 2.6.25 is differs from muram node for the 2.6.26)

With this device tree I have a warning message from cpm_uart driver
tells that the dts file needs to be updated.

Ilya.

Re: No output from SMC1 console with the 2.6.26 kernel (8xx based board)

[Ben Gardiner]

Scott Wood wrote:
> On Tue, Jul 29, 2008 at 11:33:47AM -0400, Ben Gardiner wrote:
>> CPU clock-frequency <- 0x3f940aa (67MHz)
>> CPU timebase-frequency <- 0x1fce17 (2MHz)
>> CPU bus-frequency <- 0x1fce170 (33MHz)
>>     
>
> Try commenting out calls to cpm_setbrg(), to see if the frequency is bad.
>
> -Scott
>   

Thank you, Scott. You spotted it: my bootloader (an old uboot) is 
passing not only the wrong clock freq (66.7 instead of 66 MHz) but 
because 66.7 > 66.0 it is also passing the clock freq / 2 as the bus 
freq. I got that last leap from the commit message of 
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=50530378161fa8d7837243119ed9140ee65e55d4. 
Thanks to cuboot I had an obvious place to do the fixup of the 
clock-freq but I hadn't realized that the bus-freq was wrong.

As you suggested, commenting out the call to cpm_setbrg() did the trick 
for me:
diff --git a/drivers/serial/cpm_uart/cpm_uart_cpm1.h 
b/drivers/serial/cpm_uart/cpm_uart_cpm1.h
index ddf46d3..c14a5f1 100644
--- a/drivers/serial/cpm_uart/cpm_uart_cpm1.h
+++ b/drivers/serial/cpm_uart/cpm_uart_cpm1.h
@@ -24,7 +24,7 @@ #endif
 
 static inline void cpm_set_brg(int brg, int baud)
 {
-       cpm_setbrg(brg, baud);
+       //cpm_setbrg(brg, baud);
 }

Of course I won't run with that patch. We are using cuboot, so I put 
some fixup code in our copy of cuboot-8xx.c, cuboot-nmx-taurus.c:
diff --git a/arch/powerpc/boot/cuboot-nmx-taurusc 
b/arch/powerpc/boot/cuboot-nmx-taurus.c
index c202c88..5ab2ff3 100644
--- a/arch/powerpc/boot/cuboot-nmx-taurus.c
+++ b/arch/powerpc/boot/cuboot-nmx-taurus.c
@@ -26,6 +26,12 @@ static void platform_fixups(void)
 
        dt_fixup_memory(bd.bi_memstart, bd.bi_memsize);
        dt_fixup_mac_addresses(bd.bi_enetaddr, bd.bi_enet1addr);
+       /* NMX workaround: fix board reporting wrong freq */
+       if(bd.bi_intfreq == 66700000) {
+               bd.bi_intfreq = 66666666UL;
+               bd.bi_busfreq = bd.bi_intfreq;
+       }
+       /* end NMX workaround.*/
        dt_fixup_cpu_clocks(bd.bi_intfreq, bd.bi_busfreq / 16, 
bd.bi_busfreq);
 
        node = finddevice("/soc/cpm");

NB: I realize 66666666 may be wrong. It is what was set in our 2.4 
kernel so I'm going to leave it as is for now. If I can show that it is 
causing clock drift or someone can give me a reason why it should be 
66000000 I'll change it then.

Which fixes up the values passed by Uboot:
<snip console>
...
CPU clock-frequency <- 0x3f940aa (67MHz)
CPU timebase-frequency <- 0x3f940a (4MHz)
CPU bus-frequency <- 0x3f940aa (67MHz)
...
<snip>

Thanks for your help and for cuboot.
I'm sorry to have confused this issue. It appears that Matvejchikov and 
I are having a different problem.

,Ben

Re: No output from SMC1 console with the 2.6.26 kernel (8xx based board)

[Scott Wood]

On Wed, Jul 30, 2008 at 01:37:43PM +0400, Matvejchikov Ilya wrote:
> 			smc1: serial@11a80 {
> 				device_type = "serial";
> 				compatible = "fsl,cpm2-smc-uart";
> 				reg = <11a80 20 0 40>;
> 				interrupts = <4 8>;
> 				interrupt-parent = <&PIC>;
> 				fsl,cpm-brg = <7>;
> 				fsl,cpm-command = <1d000000>;
> 			};
> 
> 		};
> 
> (muram node for 2.6.25 is differs from muram node for the 2.6.26)
> 
> With this device tree I have a warning message from cpm_uart driver
> tells that the dts file needs to be updated.

Right, but does the serial port work?  If it works with this tree and not
with the new version, then that points to a problem in the dynamic pram
allocation.  Otherwise, I'm not sure what's causing the difference
between the two versions; you may want to bisect.

-Scott

Re: No output from SMC1 console with the 2.6.26 kernel (8xx based board)

[Matvejchikov Ilya]

Hi all,

The problem was in incorrect (not full) brg-node definition. Instead of
brg@119f0 {
    compatible = "fsl,cpm-brg", "fsl,cpm2-brg";
    reg = <119f0 10 115f0 10>;
 };
there must be:
brg@119f0 {
    compatible = "fsl,cpm-brg", "fsl,cpm2-brg";
    reg = <119f0 10 115f0 10>;
    clock-frequency = <my_clock_frequency>;
 };

The PQ2 (and some others) DTS files needs to be updated.

Thanks.

Re: No output from SMC1 console with the 2.6.26 kernel (8xx based board)

[Scott Wood]

On Tue, Aug 19, 2008 at 03:13:54PM +0400, Matvejchikov Ilya wrote:
> Hi all,
> 
> The problem was in incorrect (not full) brg-node definition. Instead of
> brg@119f0 {
>     compatible = "fsl,cpm-brg", "fsl,cpm2-brg";
>     reg = <119f0 10 115f0 10>;
>  };
> there must be:
> brg@119f0 {
>     compatible = "fsl,cpm-brg", "fsl,cpm2-brg";
>     reg = <119f0 10 115f0 10>;
>     clock-frequency = <my_clock_frequency>;
>  };
> 
> The PQ2 (and some others) DTS files needs to be updated.

No, the DTS files don't need to be updated -- u-boot (or whatever
firmware you use, or the bootwrapper) needs to fill in the frequency.

-Scott

Re: No output from SMC1 console with the 2.6.26 kernel (8xx based board)

[Matvejchikov Ilya]

> No, the DTS files don't need to be updated -- u-boot (or whatever
> firmware you use, or the bootwrapper) needs to fill in the frequency.

u-boot doesn't contains any related code for this moment...
I think we need to add some code that adds "clock-frequency" property for the
"fsl,cpm-brg" compatible node to the u-boot as it expected in get_brgfreq.

Matvejchikov Ilya.