Commit Graph

12 Commits (83dcfeabf8d37e7ea1adfafcd782f1298a3ddbef)

Author SHA1 Message Date
Matt Johnston 4bd45af739 Move alt_reset to syscon
Instead of connecting core_alt_reset to litedram init_done, it moves to
a syscon register bit. This simplifies top- files and future soc_reset
handling. sdram main.c can unset the alt_reset bit after sdram init.

Signed-off-by: Matt Johnston <>
1 year ago
Benjamin Herrenschmidt 39c2abae51 Fix build of core_dram_tb and dram_tb and fix tracing
We disabled --trace by default, so we need to stop linking verilated_vcd_c.o
as it doesn't exist in that case.

While at it, make a Makefile variable to enable/disable verilator tracing
and add a couple of generics to those test benches to control tracing
in the L2 and in litedram.

Signed-off-by: Benjamin Herrenschmidt <>
1 year ago
Raptor Engineering Development Team fcb783a0fb Extend LiteDRAM VHDL wrapper to allow more than one clock line
This is necessary for the upcoming Arctic Tern system enablement,
since Arctic Tern uses two DRAM devices and a separate clock line
is routed to each device.  LiteX handles this behavior correctly,
therefore we assume other hardware exists that uses a similar
DRAM clock design.

Updates from Mikey to fix some compile issues.

Signed-off-by: Timothy Pearson <>
Signed-off-by: Michael Neuling <>
2 years ago
Anton Blanchard 21f482f967 Reformat testbenches
Signed-off-by: Anton Blanchard <>
3 years ago
Benjamin Herrenschmidt 02abb135a8 litedram: l2: Add support for more geometries
Make the DRAM data lines and user port width configurable, also
don't hard wire dependency on the wishbone data width.

Signed-off-by: Benjamin Herrenschmidt <>
3 years ago
Benjamin Herrenschmidt f9f18906a3 soc: Rename wb_dram_ctrl to wb_ext_io and rework decoding
This makes the control bus currently going out of "soc" towards
litedram more generic for external IO devices added by the
top-level rather than inside the SoC proper.

This is mostly renaming of signals and a small change on how the
address decoder operates, using a separate "cascaded" decode for
the external IOs.

We make the region 0xc8nn_nnnn be the "external IO" region for

This will make it easier / cleaner to add more external devices.

Signed-off-by: Benjamin Herrenschmidt <>
4 years ago
Benjamin Herrenschmidt 1ffc89e58b soc: Add defaults for some input signals
That way the top-level's don't need to assign them

Also remove generics that are set to the default anyways

Signed-off-by: Benjamin Herrenschmidt <>
4 years ago
Benjamin Herrenschmidt 4244b54984 soc: Remove unused RESET_LOW generic
Signed-off-by: Benjamin Herrenschmidt <>
4 years ago
Benjamin Herrenschmidt a89e1469ef spi: Add simulation support
This require the s25fl128s.vhd flash model and FMF libraries,
which will be built when passed to the Makefile via the
FLASH_MODEL_PATH argument. Otherwise a dummy module is used
which ties MISO to '1'.

The model isn't included as I'm not sure its licence (GPL) is
at this point, but it can be obtained from

FLASH_MODEL_PATH=<path to microspi>/model

Signed-off-by: Benjamin Herrenschmidt <>
4 years ago
Benjamin Herrenschmidt a93d9e77c9 litedram: Remove remnants of riscv-inits
We still had some wires bringing an extra serial port out of
litedram for the built-in riscv processor. This is all gone now
so take them out.

Signed-off-by: Benjamin Herrenschmidt <>
4 years ago
Benjamin Herrenschmidt bf1b98b958 litedram: Add support for booting without BRAM
This adds an option to disable the main BRAM and instead copy a
payload stashed along with the init code in the secondary BRAM
into DRAM and boot from there

Signed-off-by: Benjamin Herrenschmidt <>
4 years ago
Benjamin Herrenschmidt 6fe077910b litedram: Add simulation support
This adds a simulated litedram model along with the necessary
Makefile gunk to verilate it and wrap it for use by ghdl.

The core_dram_tb test bench is a variant of core_tb with
LiteDRAM simulated. It's not built by default, an explicit

make core_dram_tb

is necessary as to not require verilator to be installed for
the normal build process (also it's slow'ish).

Signed-off-by: Benjamin Herrenschmidt <>
4 years ago