On Fri, Jul 13, 2007 at 11:51:15AM +0300, Alexandros Kostopoulos wrote: > I am trying to port kernel 2.6.22.1 to my own platform, which incorporates > an mpc8275 chip. I'm using platform code for mpc82xx_ads as a template (is > this right in the first place?). I have a couple of questions:
I suggest waiting until I can get my 8xx/82xx patchset out (which should happen early next week... it would have been earlier if I hadn't gotten distracted trying to get PCI to work right). It addresses the things you point out. > 1. mpc82xx_ads.c uses init_scc_ioports function to initialize the scc > uarts. However, this function is only used by the code in > arch/powerpc/sysdev/fsl_soc.c, and spefically in fs_enet_of_init(), > which is used to initialize the ethernet driver and not the cpm_uart > driver. On the other hand, cpm_uart_of_init() function seems to be the > one that initializes the uarts in cpm, and actually makes use of the > device-id, model, rx-clock and tx-clock properties of the scc nodes in > OF tree. So, AFAICT, init_scc_ioports should not be there, since it > won't be actually called at all (although I have not actually tested > this - I haven't yet managed to boot the kernel). Instead, > cpm_uart_of_init should take care of everything, except for the pport > initialization, which is done in u-boot anyway (at least in my case). > Any thoughts on this? All such port configuration callbacks are removed in my patchset; the bootloader and/or platform code is responsible for setting it up. > 2. I have also some questions regarding the device tree. Why are there two > nodes regarding the interrupt controller in there? There are two interrupt controllers on the mpc8272ads: one for PCI, and another for everything else. > and in the top level node, what does this property means: reg = > <f8200000 f8200004>; It means the device tree is buggy. It should say <f8200000 8>. > Finally, in the memory node, the reg property defines a second mem > region, (f4500000 f4500020). What is this? More device tree brokenness. It's the board control and status register block, which has nothing to do with memory. > maybe a special memory mapped peripheral of this board? If I have a > board with many mem configurations (e.g. it uses a DIMM SDRAM what can > be changed), what value should I place in the mem node? I have to > change dts every time I insert a new DIMM? No, u-boot or the bootwrapper should fill in the memory size. -Scott _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
