litex/misoc/integration/soc_sdram.py

from migen import *
from migen.genlib.record import *

from misoc.interconnect import wishbone, wishbone2lasmi, lasmi_bus
from misoc.interconnect.csr import AutoCSR
from misoc.cores import dfii, minicon, lasmicon
from misoc.integration.soc_core import *


__all__ = ["SoCSDRAM", "soc_sdram_args", "soc_sdram_argdict"]


class ControllerInjector(Module, AutoCSR):
    def __init__(self, phy, controller_type, geom_settings, timing_settings):
        self.submodules.dfii = dfii.DFIInjector(geom_settings.addressbits, geom_settings.bankbits,
                phy.settings.dfi_databits, phy.settings.nphases)
        self.comb += Record.connect(self.dfii.master, phy.dfi)

        if controller_type == "lasmicon":
            self.submodules.controller = controller = lasmicon.LASMIcon(phy.settings,
                                                                        geom_settings,
                                                                        timing_settings)
            self.comb += Record.connect(controller.dfi, self.dfii.slave)

            self.submodules.crossbar = lasmi_bus.LASMIxbar([controller.lasmic],
                                                           controller.nrowbits)
        elif controller_type == "minicon":
            self.submodules.controller = controller = minicon.Minicon(phy.settings,
                                                                      geom_settings,
                                                                      timing_settings)
            self.comb += Record.connect(controller.dfi, self.dfii.slave)
        else:
            raise ValueError("Unsupported SDRAM controller type")


class SoCSDRAM(SoCCore):
    csr_map = {
        "sdram":           8,
        "l2_cache":        9
    }
    csr_map.update(SoCCore.csr_map)

    def __init__(self, platform, clk_freq, l2_size=8192, **kwargs):
        SoCCore.__init__(self, platform, clk_freq, **kwargs)
        self.l2_size = l2_size
        
        self._sdram_phy = []
        self._wb_sdram_ifs = []
        self._wb_sdram = wishbone.Interface()

    def add_wb_sdram_if(self, interface):
        if self.finalized:
            raise FinalizeError
        self._wb_sdram_ifs.append(interface)

    def register_sdram(self, phy, sdram_controller_type, geom_settings, timing_settings):
        assert not self._sdram_phy
        self._sdram_phy.append(phy)  # encapsulate in list to prevent CSR scanning

        self.submodules.sdram = ControllerInjector(
            phy, sdram_controller_type, geom_settings, timing_settings)

        dfi_databits_divisor = 1 if phy.settings.memtype == "SDR" else 2
        sdram_width = phy.settings.dfi_databits//dfi_databits_divisor
        main_ram_size = 2**(geom_settings.bankbits +
                            geom_settings.rowbits +
                            geom_settings.colbits)*sdram_width//8
        # XXX: Limit main_ram_size to 256MB, we should modify mem_map to allow larger memories.
        main_ram_size = min(main_ram_size, 256*1024*1024)
        if self.l2_size:
            self.add_constant("L2_SIZE", self.l2_size)

        # add a Wishbone interface to the DRAM
        wb_sdram = wishbone.Interface()
        self.add_wb_sdram_if(wb_sdram)
        self.register_mem("main_ram", self.mem_map["main_ram"], wb_sdram, main_ram_size)

        if sdram_controller_type == "lasmicon":
            if self.l2_size:
                lasmim = self.sdram.crossbar.get_master()
                l2_cache = wishbone.Cache(self.l2_size//4, self._wb_sdram, wishbone.Interface(lasmim.dw))
                # XXX Vivado ->2015.1 workaround, Vivado is not able to map correctly our L2 cache.
                # Issue is reported to Xilinx and should be fixed in next releases (2015.2?).
                # Remove this workaround when fixed by Xilinx.
                from migen.build.xilinx.vivado import XilinxVivadoToolchain
                if isinstance(self.platform.toolchain, XilinxVivadoToolchain):
                    from migen.fhdl.simplify import FullMemoryWE
                    self.submodules.l2_cache = FullMemoryWE()(l2_cache)
                else:
                    self.submodules.l2_cache = l2_cache
                self.submodules.wishbone2lasmi = wishbone2lasmi.WB2LASMI(self.l2_cache.slave, lasmim)
        elif sdram_controller_type == "minicon":
            if self.l2_size:
                l2_cache = wishbone.Cache(self.l2_size//4, self._wb_sdram, self.sdram.controller.bus)
                # XXX Vivado ->2015.1 workaround, Vivado is not able to map correctly our L2 cache.
                # Issue is reported to Xilinx and should be fixed in next releases (2015.2?).
                # Remove this workaround when fixed by Xilinx.
                from migen.build.xilinx.vivado import XilinxVivadoToolchain
                if isinstance(self.platform.toolchain, XilinxVivadoToolchain):
                    from migen.fhdl.simplify import FullMemoryWE
                    self.submodules.l2_cache = FullMemoryWE()(l2_cache)
                else:
                    self.submodules.l2_cache = l2_cache
            else:
                self.submodules.converter = wishbone.Converter(self._wb_sdram, self.sdram.controller.bus)
        else:
            raise ValueError

    def do_finalize(self):
        if not self.integrated_main_ram_size:
            if not self._sdram_phy:
                raise FinalizeError("Need to call SDRAMSoC.register_sdram()")

            # arbitrate wishbone interfaces to the DRAM
            self.submodules.wb_sdram_con = wishbone.Arbiter(self._wb_sdram_ifs,
                                                            self._wb_sdram)
        SoCCore.do_finalize(self)


soc_sdram_args = soc_core_args
soc_sdram_argdict = soc_core_argdict