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oh/edma/hdl/edma.v
Andreas Olofsson 0cc00dcd2e Changed DMA interface to "packet style"
-Packet format is really compact, a huge deal after all..
-Also commenting out content for now
2015-05-01 17:30:08 -04:00

223 lines
7.3 KiB
Verilog

module edma (/*AUTOARG*/
// Outputs
mi_dout, edma_access, edma_packet,
// Inputs
reset, clk, mi_en, mi_we, mi_addr, mi_din, edma_wait
);
/******************************/
/*Compile Time Parameters */
/******************************/
parameter RFAW = 6;
parameter AW = 32;
parameter DW = 32;
parameter PW = 104;
/******************************/
/*HARDWARE RESET (EXTERNAL) */
/******************************/
input reset;
input clk;
/*****************************/
/*REGISTER INTERFACE */
/*****************************/
input mi_en;
input mi_we;
input [RFAW+1:0] mi_addr;
input [63:0] mi_din;
output [31:0] mi_dout;
/*****************************/
/*DMA TRANSACTION */
/*****************************/
output edma_access;
output [PW-1:0] edma_packet;
input edma_wait;
/*
//registers
reg [AW-1:0] edma_srcaddr_reg;
reg [AW-1:0] edma_dstaddr_reg;
reg [AW-1:0] edma_count_reg;
reg [AW-1:0] edma_stride_reg;
reg [8:0] edma_cfg_reg;
reg [1:0] edma_status_reg;
reg [31:0] mi_dout;
//wires
wire edma_write;
wire edma_read;
wire edma_cfg_write ;
wire edma_srcaddr_write;
wire edma_dstaddr_write;
wire edma_stride_write;
wire edma_count_write;
wire edma_message;
wire edma_expired;
wire edma_last_tran;
wire edma_error;
wire edma_enable;
//read/write decode
assign edma_write = mi_en & mi_we;
assign edma_read = mi_en & ~mi_we;
//DMA configuration
assign edma_cfg_write = edma_write & (mi_addr[RFAW+1:2]==`EDMACFG);
assign edma_srcaddr_write = edma_write & (mi_addr[RFAW+1:2]==`EDMASRCADDR);
assign edma_dstaddr_write = edma_write & (mi_addr[RFAW+1:2]==`EDMADSTADDR);
assign edma_count_write = edma_write & (mi_addr[RFAW+1:2]==`EDMACOUNT);
assign edma_stride_write = edma_write & (mi_addr[RFAW+1:2]==`EDMASTRIDE);
//###########################
//# DMACFG
//###########################
always @ (posedge clk or posedge reset)
if(reset)
edma_cfg_reg[8:0] <= 'd0;
else if (edma_cfg_write)
edma_cfg_reg[8:0] <= mi_din[8:0];
assign edma_enable = edma_cfg_reg[0]; //should be zero
assign edma_message = edma_cfg_reg[8];
assign edma_access = edma_enable & ~edma_expired;
assign edma_write = edma_cfg_reg[1]; //only 1 for test pattern
assign edma_datamode[1:0] = edma_cfg_reg[3:2];
assign edma_ctrlmode[3:0] = (edma_message & edma_last_tran) ? 4'b1100 : edma_cfg_reg[7:4];
//###########################
//# DMASTATUS
//###########################
//Misalignment
assign edma_error = ((edma_srcaddr_reg[0] | edma_dstaddr_reg[0]) & (edma_datamode[1:0]!=2'b00)) | //16/32/64
((edma_srcaddr_reg[1] | edma_dstaddr_reg[1]) & (edma_datamode[1])) | //32/64
((edma_srcaddr_reg[2] | edma_dstaddr_reg[2]) & (edma_datamode[1:0]==2'b11)); //64
always @ (posedge clk or posedge reset)
if(reset)
edma_status_reg[1:0] <= 'd0;
else if (edma_cfg_write)
edma_status_reg[1:0] <= mi_din[1:0];
else if (edma_enable)
begin
edma_status_reg[0] <= edma_enable & ~edma_expired;//dma busy
edma_status_reg[1] <= edma_status_reg[1] | (edma_enable & edma_error);
end
//###########################
//# EDMASRCADDR
//###########################
always @ (posedge clk or posedge reset)
if(reset)
edma_srcaddr_reg[AW-1:0] <= 'd0;
else if (edma_srcaddr_write)
edma_srcaddr_reg[AW-1:0] <= mi_din[AW-1:0];
else if (edma_enable & ~edma_wait)
edma_srcaddr_reg[AW-1:0] <= edma_srcaddr_reg[AW-1:0] + (1<<edma_datamode[1:0]);
assign edma_srcaddr[31:0] = edma_srcaddr_reg[31:0];
//###########################
//# EDMADSTADR
//###########################
always @ (posedge clk or posedge reset)
if(reset)
edma_dstaddr_reg[AW-1:0] <= 'd0;
else if (edma_dstaddr_write)
edma_dstaddr_reg[AW-1:0] <= mi_din[AW-1:0];
else if (edma_enable & ~edma_wait)
edma_dstaddr_reg[AW-1:0] <= edma_dstaddr_reg[AW-1:0] + (1<<edma_datamode[1:0]);
assign edma_dstaddr[31:0] = edma_dstaddr_reg[31:0];
//###########################
//# EDMACOUNT
//###########################
always @ (posedge clk or posedge reset)
if(reset)
edma_count_reg[AW-1:0] <= 'd0;
else if (edma_count_write)
edma_count_reg[AW-1:0] <= mi_din[AW-1:0];
else if (edma_enable & ~edma_wait)
edma_count_reg[AW-1:0] <= edma_count_reg[AW-1:0] - 1'b1;
assign edma_last_tran = (edma_count_reg[AW-1:0]==32'b1);
assign edma_expired = (edma_count_reg[AW-1:0]==32'b0);
//###########################
//# EDMASTRIDE
//###########################
//NOTE: not supported yet, need to think about feature...
always @ (posedge clk or posedge reset)
if(reset)
edma_stride_reg[AW-1:0] <= 'd0;
else if (edma_stride_write)
edma_stride_reg[AW-1:0] <= mi_din[AW-1:0];
//###########################
//# DUMMY DATA
//###########################
assign edma_data[31:0] = TEST_PATTERN;
//###########################
//# PACKET CREATION
//###########################
emesh2packet e2p (
// Outputs
.packet_out (edma_packet[PW-1:0]),
// Inputs
.access_in (edma_access),
.write_in (edma_write),
.datamode_in (edma_datamode[1:0]),
.ctrlmode_in (edma_ctrlmode[3:0]),
.dstaddr_in (edma_dstaddr[AW-1:0]),
.data_in (edma_data[DW-1:0]),
.srcaddr_in (edma_srcaddr_in[AW-1:0]));
//###############################
//# DATA READBACK MUX
//###############################
//Pipelineing readback
always @ (posedge clk)
if(edma_read)
case(mi_addr[RFAW+1:2])
`EDMACFG: mi_dout[31:0] <= {23'b0, edma_cfg_reg[8:0]};
`EDMASTATUS: mi_dout[31:0] <= {30'b0, edma_status_reg[1:0]};
`EDMASRCADDR:mi_dout[31:0] <= {edma_srcaddr_reg[31:0]};
`EDMADSTADDR:mi_dout[31:0] <= {edma_dstaddr_reg[31:0]};
`EDMACOUNT: mi_dout[31:0] <= {edma_count_reg[31:0]};
default: mi_dout[31:0] <= 32'd0;
endcase // case (mi_addr[RFAW+1:2])
else
begin
default: mi_dout[31:0] <= 32'd0;
end
*/
endmodule // edma
// Local Variables:
// verilog-library-directories:("." "../../common/hdl")
// End:
/*
Copyright (C) 2013 Adapteva, Inc.
Contributed by Andreas Olofsson <andreas@adapteva.com>
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.This program is distributed in the hope
that it will be useful,but WITHOUT ANY WARRANTY; without even the implied
warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details. You should have received a copy
of the GNU General Public License along with this program (see the file
COPYING). If not, see <http://www.gnu.org/licenses/>.
*/