cross-compiling Linux for PowerPC e200 core?
Grant Likely
grant.likely at secretlab.ca
Tue Mar 9 18:35:40 EST 2010
2010/3/9 Németh Márton <nm127 at freemail.hu>:
> Hi,
> Grant Likely wrote:
>> 2010/3/8 Németh Márton <nm127 at freemail.hu>:
>>> Grant Likely wrote:
>>>> 2010/3/6 Németh Márton <nm127 at freemail.hu>:
>>>>> Hi,
>>>>>
>>>>> I'm trying to cross-compile Linux 2.6.33 for Freescale MPC5554 [1][2]. This
>>>>> microcontroller is based on the e200z6 core. I could build the cross-development
>>>>> tools, but I could miss something because I get an error message when building
>>>>> Linux for PowerPC e200 core. Here are the steps I used:
>>>> I doubt you'll have much luck with the mpc5554. Linux doesn't include
>>>> any support for the MPC5554, and I don't think anybody is working on
>>>> it. Any of the mpc5554 systems I've see don't have enough ram to run
>>>> Linux well.
>>> I'm ready to work a bit more than just compiling the kernel and run it on MPC5554.
>>> On my target system there is a possibility to use external RAM connected to the
>>> External Bus Interface, so I don't see this would be a problem in my case.
>>>
>>> However, I have not much experience running Linux on PowerPC environment. Could
>>> you suggest a PowerPC port which would be a good starting point to make support
>>> for MPC5554?
>>
>> I'd use the MPC5200 board support as a starting point
>> (arch/powerpc/platforms/52xx). Create yourself a new directory for
>> this platform (arch/powerpc/platforms/55xx)
>>
>>> As far as I could find out I'll need to create a device tree as documented in
>>> the linux/Documentation/powerpc/booting-without-of.txt file.
>>
>> Yes, you'll need to create a device tree file for the board. Again,
>> start from an existing 5200 .dts file. You won't need very much in it
>> to get started. I'd be happy to help you get the structure right.
>
> I tried to create a first draft of the deveice tree for MPC5554. It is
> compilable with dtc. I based this .dts file on Figure 1-1 on page 1-3 and
> Table 1-2 on page 1-21 of http://www.freescale.com/files/32bit/doc/ref_manual/MPC5553_MPC5554_RM.pdf .
>
> I'm not sure about the following points:
> 1. Where should be the on-chip FLASH described? This memory is read-only from
> view of software and can be used to store read-only data or execute code directly
> from there.
Hang it off the xbar node. Name it flash@<address>, and use
'compatible = "fsl,mpc5554-flash";'
>
> 2. Should the co-processor (eTPU in this case) also listed in section "cpus"
> or not? This co-processor is not able to run code like the e200z6.
No, this is a device. Hang it off the peripheral bridge a node.
> 3. There are three on-chip buses on MPC5554:
> - Crossbar Switch (XBAR)
> - Peripheral Bridge A (PBRIDGE_A)
> - Peripheral Bridge B (PBRIDGE_B)
> I used PBRIDGE_A and PRIDGE_B to create two /soc<SOCname> entries. Is this possible?
the soc5200 naming was poorly chosen when the 5200 device tree was
written. Use something like this:
xbar@<control-regs-base-address> {
compatible = "fsl,mpc5554-xbar";
#address-cells = <1>;
#size-cells = <1>;
ranges = <[put the translation ranges in here]>;
reg = <address and size of xbar control registers>;
bridge@<bridgea-base-address> {
compatible = "fsl,mpc5554-pbridge-a";
#address-cells = <1>;
#size-cells = <1>;
ranges = <[put the translation ranges in here]>;
reg = <address and size of bridge control registers>;
[... child device nodes ...]
};
bridge@<bridgea-base-address> {
compatible = "fsl,mpc5554-pbridge-b";
#address-cells = <1>;
#size-cells = <1>;
ranges = <[put the translation ranges in here]>;
reg = <address and size of bridge control registers>;
[... child device nodes ...]
};
};
The idea is to use generic names for the node names, and identify
exactly what the device is by using the "compatible" property. Also,
the aim is to build up a tree describing the interconnection of device
from the perspective of the OS on the CPU. ie. the full physical
address space is represented by the root node of the tree, and
everything else hangs off that.
> 4. There are modules which have multiple instances at different base addresses. These
> are DSPI, SCI and FlexCAN. I used the same name for them but with different addresses.
> Is this correct?
yes.
> +/ {
> + model = "MPC5554";
> + compatible = "MPC5554";
Use the board name here in the form "<manufacturer>,<board>", not the SoC name.
> + #address-cells = <1>;
> + #size-cells = <1>;
> +
> + cpus {
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + PowerPC,5554 at 0 {
> + device_type = "cpu";
> + reg = <0>;
> + d-cache-line-size = <32>;
> + i-cache-line-size = <32>;
> + d-cache-size = <0x8000>; // L1, 32KiB
> + i-cache-size = <0x8000>; // L1, 32KiB
> + timebase-frequency = <0>; // from bootloader
> + bus-frequency = <0>; // from bootloader
> + clock-frequency = <0>; // from bootloader
> + };
> + };
> +
> + flash { // read-only FLASH
flash at 0
> + device_type = "memory";
> + reg = <0x00000000 0x200000>; // 2MiB internal FLASH
> + };
remove device_type from this node. Only a few special nodes should
have device_type. Make the flash node a child of the xbar node.
> +
> + memory {
memory at 400000000
> + device_type = "memory";
> + reg = <0x40000000 0x10000>; // 32KiB internal SRAM
> + };
> +
> + soc5554BridgeA at c0000000 {
bridge at c0000000
Make this node a child of the xbar node.
> + #address-cells = <1>;
> + #size-cells = <1>;
> + compatible = "fsl,mpc5554-bridgea";
> + ranges = <0 0xc0000000 0x20000000>;
> + reg = <0xc0000000 0x20000000>;
The reg property here should only cover the bridge's control register.
Not the whole range of the bridge.
> + bus-frequency = <0>; // from bootloader
> + system-frequency = <0>; // from bootloader
> +
> + bridgea at 3f00000 {
> + compatible = "fsl,mpc5554-bridgea";
> + reg = <0x03f00000 0x4000>;
> + };
> +
> + fmpll at 3f80000 { // Frequency Modulated PLL
> + compatible = "fsl,mpc5554-fmpll";
> + reg = <0x03f80000 0x4000>;
> + };
> +
> + flashconfig at 3f88000 { // Flash Configuration
> + compatible = "fsl,mpc5554-flashconfig";
> + reg = <0x03f88000 0x4000>;
> + };
> +
> + siu at 3f89000 { // System Integration Unit
> + compatible = "fsl,mpc5554-siu";
> + reg = <0x03f90000 0x4000>;
> + };
> +
> + emios at 3fa0000 { // Modular Timer System
> + compatible = "fsl,mpc5554-emios";
> + reg = <0x03fa0000 0x4000>;
> + };
> +
> + etpu at 3fc0000 { // Enhanced Time Processing Unit
> + compatible = "fsl,mpc5554-etpu";
> + reg = <0x03fc0000 0x4000>;
> + };
> +
> + etpudata at 3fc8000 { // eTPU Shared Data Memory (Parameter RAM)
> + compatible = "fsl,mpc5554-etpudata";
> + reg = <0x03fc8000 0x4000>;
> + };
> +
> + etpudata at 3fcc000 { // eTPU Shared Data Memory (Parameter RAM) mirror
> + compatible = "fsl,mpc5554-etpudata";
> + reg = <0x03fcc000 0x4000>;
> + };
> +
> + etpucode at 3fd0000 { // eTPU Shared Code RAM
> + compatible = "fsl,mpc5554-etpucode";
> + reg = <0x03fd0000 0x4000>;
> + };
> + };
> +
> + soc5554BridgeB at e0000000 {
bridge at e0000000
> + #address-cells = <1>;
> + #size-cells = <1>;
> + compatible = "fsl,mpc5554-bridgeb";
> + ranges = <0 0xe0000000 0x20000000>;
> + reg = <0xe0000000 0x20000000>;
ditto on comment from bridge a
> + bus-frequency = <0>; // from bootloader
> + system-frequency = <0>; // from bootloader
> +
> + bridgeb at 1ff00000 {
> + compatible = "fsl,mpc5554-bridgeb";
> + reg = <0x1ff00000 0x4000>;
> + };
> +
> + xbar at 1ff04000 { // System Bus Crossbar Switch (XBAR)
> + compatible = "fsl,mpc5554-xbar";
> + reg = <0x1ff04000 0x4000>;
> + };
The block diagram seems to suggest that the xbar should be the root of
the tree, and the peripheral bridges should be children of it.
> +
> + ecsm at 1ff40000 { // Error Correction Status Module (ECSM)
> + compatible = "fsl,mpc5554-ecsm";
> + reg = <0x1ff40000 0x4000>;
> + };
> +
> + edma at 1ff44000 { // Enhanced DMA Controller (eDMA)
> + compatible = "fsl,mpc5554-edma";
> + reg = <0x1ff44000 0x4000>;
> + };
> +
> + intc at 1ff48000 { // Interrupt Controller (INTC)
> + compatible = "fsl,mpc5554-intc";
> + reg = <0x1ff48000 0x4000>;
> + };
> +
> + eqadc at 1ff80000 { // Enhanced Queued Analog-to-Digital Converter (eQADC)
> + compatible = "fsl,mpc5554-eqacd";
> + reg = <0x1ff80000 0x4000>;
> + };
> +
> + dspi at 1ff90000 { // Deserial Serial Peripheral Interface (DSPI_A)
> + compatible = "fsl,mpc5554-dspi";
> + reg = <0x1ff90000 0x4000>;
> + };
> +
> + dspi at 1ff94000 { // Deserial Serial Peripheral Interface (DSPI_B)
> + compatible = "fsl,mpc5554-dspi";
> + reg = <0x1ff94000 0x4000>;
> + };
> +
> + dspi at 1ff98000 { // Deserial Serial Peripheral Interface (DSPI_C)
> + compatible = "fsl,mpc5554-dspi";
> + reg = <0x1ff98000 0x4000>;
> + };
> +
> + dspi at 1ff9c000 { // Deserial Serial Peripheral Interface (DSPI_D)
> + compatible = "fsl,mpc5554-dspi";
> + reg = <0x1ff9c000 0x4000>;
> + };
> +
> + sci at 1ffb0000 { // Serial Communications Interface (SCI_A)
> + compatible = "fsl,mpc5554-sci";
> + reg = <0x1ffb0000 0x4000>;
> + };
> +
> + sci at 1ffb4000 { // Serial Communications Interface (SCI_A)
> + compatible = "fsl,mpc5554-sci";
> + reg = <0x1ffb4000 0x4000>;
> + };
> +
> + can at 1ffc0000 { // Controller Area Network (FlexCAN_A)
> + compatible = "fsl,mpc5554-flexcan";
> + reg = <0x1ffc0000 0x4000>;
> + };
> +
> + can at 1ffc4000 { // Controller Area Network (FlexCAN_B)
> + compatible = "fsl,mpc5554-flexcan";
> + reg = <0x1ffc4000 0x4000>;
> + };
> +
> + can at 1ffc8000 { // Controller Area Network (FlexCAN_C)
> + compatible = "fsl,mpc5554-flexcan";
> + reg = <0x1ffc8000 0x4000>;
> + };
> +
> + bam at 1fffc000 { // Boot Assist Module (BAM)
> + compatible = "fsl,mpc5554-bam";
> + reg = <0x1fffc000 0x4000>;
> + };
> +
> + };
> +
> +};
>
>
--
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.
More information about the Linuxppc-dev
mailing list