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Diffstat (limited to 'c/src/lib/libbsp/shared/vmeUniverse/README.porting')
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diff --git a/c/src/lib/libbsp/shared/vmeUniverse/README.porting b/c/src/lib/libbsp/shared/vmeUniverse/README.porting new file mode 100644 index 0000000000..b72a673356 --- /dev/null +++ b/c/src/lib/libbsp/shared/vmeUniverse/README.porting @@ -0,0 +1,88 @@ +# +# $Id$ +# + +The vmeUniverse driver needs some support from the BSP for + +a) PCI configuration space access +b) PCI interrupt acknowledgement +c) PCI interrupt handler installation + +The driver was developed using the powerpc/shared/ BSP +(it also supports vxWorks) and by default uses that BSP's +a) PCI access API +b,c) irq handling API (AKA 'new' style BSP_install_rtems_irq_handler() + API). + +Some hooks exist in the driver to ease porting to other BSPs. +The following information has been assembled when answering a +question regarding a ppcn_60x BSP port: + +I looked through the ppcn_60x BSP. Here's what I found: + + - this BSP does NOT adhere to neither the 'old' nor the 'new' API + but provides its own (startup/setvec.c: set_vector()). + - the BSP has a 'driver' for vmeUniverse although mine is far more + complete (including support for VME interrupts, DMA etc.). + - Porting my driver to your BSP should not be too hard: + + 1) vmeUniverse needs PCI configuration space support from the + BSP: + a) a routine 'pciFindDevice' (need to be macro-aliased + to the proper routine/wrapper of your BSP) who scans + PCI config space for the universe bridge. + You could add 'libbsp/powerpc/shared/pci/pcifinddevice.c' + to your BSP substituting the pci_read_config_xxx calls + by the ones present on your BSP (see step 2)) + b) routines to read PCI config registers (byte and longword) + [on your BSP these are PCIConfigRead32/PCIConfigRead8; + hence you could replace the macros on top with + #define pciConfigInLong PCIConfigRead32 + 2) vmeUniverse needs to know how to acknowledge a PCI interrupt + In your case, nothing needs to be done + #define BSP_PIC_DO_EOI do {} while (0) + 3) Install the VME ISR dispatcher: replace the 'new' style + interrupt installer (BSP_install_rtems_irq_handler()) by + a proper call to 'set_vector()' + 4) I might have missed something... + +I attach the latest version of the vmeUniverse driver in case you want +to try to do the port (should be easy). + +For the sake of ease of maintenance, I just added a few hooks making it +possible to override some things without having to modify the driver code. + + 1,2) PCI config space access macros may be overriden via CFLAGS + when compiling vmeUniverse.c, hence: + CFLAGS += -DBSP_PIC_DO_EOI=do{}while(0) + CFLAGS += -DBSP_PCI_CONFIG_IN_LONG=PCIConfigRead32 + CFLAGS += -DBSP_PCI_CONFIG_IN_BYTE=PCIConfigRead8 + (you still need to supply BSP_pciFindDevice) + 3) create your own version of vmeUniverseInstallIrqMgr(): + copy to a separate file and replace + BSP_rtems_install_irq_handler() by a proper call to set_vector. + + 4) Send me email :-) + +USAGE NOTE: To fully initialize the driver, the following steps can/must +be performed: + + vmeUniverseInit(); /* MANDATORY: Driver Initialization */ + vmeUniverseReset(); /* OPTIONAL: Reset most registers to a known state; + * if this step is omitted, firmware setup is + * preserved + */ + vmeUniverseMasterPortCfg(...); /* OPTIONAL: setup the master windows + * (current setup preserved if omitted) + */ + vmeUniverseSlavePortCfg(...); /* OPTIONAL: setup the slave windows + * (current setup preserved if omitted) + */ + vmeUniverseInstallIrqMgr(); /* NEEDED FOR VME INTERRUPT SUPPRORT + * initialize the interrupt manager. + * NOTE: you need to call your own + * version of this routine here + */ + +For an example of init/setup, consult libbsp/powerpc/shared/vme/vmeconfig.c + |