409 lines
		
	
	
		
			8.5 KiB
		
	
	
	
		
			Ucode
		
	
	
	
	
	
			
		
		
	
	
			409 lines
		
	
	
		
			8.5 KiB
		
	
	
	
		
			Ucode
		
	
	
	
	
	
| /*
 | |
|  * RX ucode for the Intel IXP2400 in POS-PHY mode.
 | |
|  * Copyright (C) 2004, 2005 Lennert Buytenhek
 | |
|  * Dedicated to Marija Kulikova.
 | |
|  *
 | |
|  * 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 2 of the License, or
 | |
|  * (at your option) any later version.
 | |
|  *
 | |
|  * Assumptions made in this code:
 | |
|  * - The IXP2400 MSF is configured for POS-PHY mode, in a mode where
 | |
|  *   only one full element list is used.  This includes, for example,
 | |
|  *   1x32 SPHY and 1x32 MPHY32, but not 4x8 SPHY or 1x32 MPHY4.  (This
 | |
|  *   is not an exhaustive list.)
 | |
|  * - The RBUF uses 64-byte mpackets.
 | |
|  * - RX descriptors reside in SRAM, and have the following format:
 | |
|  *	struct rx_desc
 | |
|  *	{
 | |
|  *	// to uengine
 | |
|  *		u32	buf_phys_addr;
 | |
|  *		u32	buf_length;
 | |
|  *
 | |
|  *	// from uengine
 | |
|  *		u32	channel;
 | |
|  *		u32	pkt_length;
 | |
|  *	};
 | |
|  * - Packet data resides in DRAM.
 | |
|  * - Packet buffer addresses are 8-byte aligned.
 | |
|  * - Scratch ring 0 is rx_pending.
 | |
|  * - Scratch ring 1 is rx_done, and has status condition 'full'.
 | |
|  * - The host triggers rx_done flush and rx_pending refill on seeing INTA.
 | |
|  * - This code is run on all eight threads of the microengine it runs on.
 | |
|  *
 | |
|  * Local memory is used for per-channel RX state.
 | |
|  */
 | |
| 
 | |
| #define RX_THREAD_FREELIST_0		0x0030
 | |
| #define RBUF_ELEMENT_DONE		0x0044
 | |
| 
 | |
| #define CHANNEL_FLAGS			*l$index0[0]
 | |
| #define CHANNEL_FLAG_RECEIVING		1
 | |
| #define PACKET_LENGTH			*l$index0[1]
 | |
| #define PACKET_CHECKSUM			*l$index0[2]
 | |
| #define BUFFER_HANDLE			*l$index0[3]
 | |
| #define BUFFER_START			*l$index0[4]
 | |
| #define BUFFER_LENGTH			*l$index0[5]
 | |
| 
 | |
| #define CHANNEL_STATE_SIZE		24	// in bytes
 | |
| #define CHANNEL_STATE_SHIFT		5	// ceil(log2(state size))
 | |
| 
 | |
| 
 | |
| 	.sig volatile sig1
 | |
| 	.sig volatile sig2
 | |
| 	.sig volatile sig3
 | |
| 
 | |
| 	.sig mpacket_arrived
 | |
| 	.reg add_to_rx_freelist
 | |
| 	.reg read $rsw0, $rsw1
 | |
| 	.xfer_order $rsw0 $rsw1
 | |
| 
 | |
| 	.reg zero
 | |
| 
 | |
| 	/*
 | |
| 	 * Initialise add_to_rx_freelist.
 | |
| 	 */
 | |
| 	.begin
 | |
| 		.reg temp
 | |
| 		.reg temp2
 | |
| 
 | |
| 		immed[add_to_rx_freelist, RX_THREAD_FREELIST_0]
 | |
| 		immed_w1[add_to_rx_freelist, (&$rsw0 | (&mpacket_arrived << 12))]
 | |
| 
 | |
| 		local_csr_rd[ACTIVE_CTX_STS]
 | |
| 		immed[temp, 0]
 | |
| 		alu[temp2, temp, and, 0x1f]
 | |
| 		alu_shf[add_to_rx_freelist, add_to_rx_freelist, or, temp2, <<20]
 | |
| 		alu[temp2, temp, and, 0x80]
 | |
| 		alu_shf[add_to_rx_freelist, add_to_rx_freelist, or, temp2, <<18]
 | |
| 	.end
 | |
| 
 | |
| 	immed[zero, 0]
 | |
| 
 | |
| 	/*
 | |
| 	 * Skip context 0 initialisation?
 | |
| 	 */
 | |
| 	.begin
 | |
| 		br!=ctx[0, mpacket_receive_loop#]
 | |
| 	.end
 | |
| 
 | |
| 	/*
 | |
| 	 * Initialise local memory.
 | |
| 	 */
 | |
| 	.begin
 | |
| 		.reg addr
 | |
| 		.reg temp
 | |
| 
 | |
| 		immed[temp, 0]
 | |
| 	init_local_mem_loop#:
 | |
| 		alu_shf[addr, --, b, temp, <<CHANNEL_STATE_SHIFT]
 | |
| 		local_csr_wr[ACTIVE_LM_ADDR_0, addr]
 | |
| 		nop
 | |
| 		nop
 | |
| 		nop
 | |
| 
 | |
| 		immed[CHANNEL_FLAGS, 0]
 | |
| 
 | |
| 		alu[temp, temp, +, 1]
 | |
| 		alu[--, temp, and, 0x20]
 | |
| 		beq[init_local_mem_loop#]
 | |
| 	.end
 | |
| 
 | |
| 	/*
 | |
| 	 * Initialise signal pipeline.
 | |
| 	 */
 | |
| 	.begin
 | |
| 		local_csr_wr[SAME_ME_SIGNAL, (&sig1 << 3)]
 | |
| 		.set_sig sig1
 | |
| 
 | |
| 		local_csr_wr[SAME_ME_SIGNAL, (&sig2 << 3)]
 | |
| 		.set_sig sig2
 | |
| 
 | |
| 		local_csr_wr[SAME_ME_SIGNAL, (&sig3 << 3)]
 | |
| 		.set_sig sig3
 | |
| 	.end
 | |
| 
 | |
| mpacket_receive_loop#:
 | |
| 	/*
 | |
| 	 * Synchronise and wait for mpacket.
 | |
| 	 */
 | |
| 	.begin
 | |
| 		ctx_arb[sig1]
 | |
| 		local_csr_wr[SAME_ME_SIGNAL, (0x80 | (&sig1 << 3))]
 | |
| 
 | |
| 		msf[fast_wr, --, add_to_rx_freelist, 0]
 | |
| 		.set_sig mpacket_arrived
 | |
| 		ctx_arb[mpacket_arrived]
 | |
| 		.set $rsw0 $rsw1
 | |
| 	.end
 | |
| 
 | |
| 	/*
 | |
| 	 * We halt if we see {inbparerr,parerr,null,soperror}.
 | |
| 	 */
 | |
| 	.begin
 | |
| 		alu_shf[--, 0x1b, and, $rsw0, >>8]
 | |
| 		bne[abort_rswerr#]
 | |
| 	.end
 | |
| 
 | |
| 	/*
 | |
| 	 * Point local memory pointer to this channel's state area.
 | |
| 	 */
 | |
| 	.begin
 | |
| 		.reg chanaddr
 | |
| 
 | |
| 		alu[chanaddr, $rsw0, and, 0x1f]
 | |
| 		alu_shf[chanaddr, --, b, chanaddr, <<CHANNEL_STATE_SHIFT]
 | |
| 		local_csr_wr[ACTIVE_LM_ADDR_0, chanaddr]
 | |
| 		nop
 | |
| 		nop
 | |
| 		nop
 | |
| 	.end
 | |
| 
 | |
| 	/*
 | |
| 	 * Check whether we received a SOP mpacket while we were already
 | |
| 	 * working on a packet, or a non-SOP mpacket while there was no
 | |
| 	 * packet pending.  (SOP == RECEIVING -> abort)  If everything's
 | |
| 	 * okay, update the RECEIVING flag to reflect our new state.
 | |
| 	 */
 | |
| 	.begin
 | |
| 		.reg temp
 | |
| 		.reg eop
 | |
| 
 | |
| 		#if CHANNEL_FLAG_RECEIVING != 1
 | |
| 		#error CHANNEL_FLAG_RECEIVING is not 1
 | |
| 		#endif
 | |
| 
 | |
| 		alu_shf[temp, 1, and, $rsw0, >>15]
 | |
| 		alu[temp, temp, xor, CHANNEL_FLAGS]
 | |
| 		alu[--, temp, and, CHANNEL_FLAG_RECEIVING]
 | |
| 		beq[abort_proterr#]
 | |
| 
 | |
| 		alu_shf[eop, 1, and, $rsw0, >>14]
 | |
| 		alu[CHANNEL_FLAGS, temp, xor, eop]
 | |
| 	.end
 | |
| 
 | |
| 	/*
 | |
| 	 * Copy the mpacket into the right spot, and in case of EOP,
 | |
| 	 * write back the descriptor and pass the packet on.
 | |
| 	 */
 | |
| 	.begin
 | |
| 		.reg buffer_offset
 | |
| 		.reg _packet_length
 | |
| 		.reg _packet_checksum
 | |
| 		.reg _buffer_handle
 | |
| 		.reg _buffer_start
 | |
| 		.reg _buffer_length
 | |
| 
 | |
| 		/*
 | |
| 		 * Determine buffer_offset, _packet_length and
 | |
| 		 * _packet_checksum.
 | |
| 		 */
 | |
| 		.begin
 | |
| 			.reg temp
 | |
| 
 | |
| 			alu[--, 1, and, $rsw0, >>15]
 | |
| 			beq[not_sop#]
 | |
| 
 | |
| 			immed[PACKET_LENGTH, 0]
 | |
| 			immed[PACKET_CHECKSUM, 0]
 | |
| 
 | |
| 		not_sop#:
 | |
| 			alu[buffer_offset, --, b, PACKET_LENGTH]
 | |
| 			alu_shf[temp, 0xff, and, $rsw0, >>16]
 | |
| 			alu[_packet_length, buffer_offset, +, temp]
 | |
| 			alu[PACKET_LENGTH, --, b, _packet_length]
 | |
| 
 | |
| 			immed[temp, 0xffff]
 | |
| 			alu[temp, $rsw1, and, temp]
 | |
| 			alu[_packet_checksum, PACKET_CHECKSUM, +, temp]
 | |
| 			alu[PACKET_CHECKSUM, --, b, _packet_checksum]
 | |
| 		.end
 | |
| 
 | |
| 		/*
 | |
| 		 * Allocate buffer in case of SOP.
 | |
| 		 */
 | |
| 		.begin
 | |
| 			.reg temp
 | |
| 
 | |
| 			alu[temp, 1, and, $rsw0, >>15]
 | |
| 			beq[skip_buffer_alloc#]
 | |
| 
 | |
| 			.begin
 | |
| 				.sig zzz
 | |
| 				.reg read $stemp $stemp2
 | |
| 				.xfer_order $stemp $stemp2
 | |
| 
 | |
| 			rx_nobufs#:
 | |
| 				scratch[get, $stemp, zero, 0, 1], ctx_swap[zzz]
 | |
| 				alu[_buffer_handle, --, b, $stemp]
 | |
| 				beq[rx_nobufs#]
 | |
| 
 | |
| 				sram[read, $stemp, _buffer_handle, 0, 2],
 | |
| 								ctx_swap[zzz]
 | |
| 				alu[_buffer_start, --, b, $stemp]
 | |
| 				alu[_buffer_length, --, b, $stemp2]
 | |
| 			.end
 | |
| 
 | |
| 		skip_buffer_alloc#:
 | |
| 		.end
 | |
| 
 | |
| 		/*
 | |
| 		 * Resynchronise.
 | |
| 		 */
 | |
| 		.begin
 | |
| 			ctx_arb[sig2]
 | |
| 			local_csr_wr[SAME_ME_SIGNAL, (0x80 | (&sig2 << 3))]
 | |
| 		.end
 | |
| 
 | |
| 		/*
 | |
| 		 * Synchronise buffer state.
 | |
| 		 */
 | |
| 		.begin
 | |
| 			.reg temp
 | |
| 
 | |
| 			alu[temp, 1, and, $rsw0, >>15]
 | |
| 			beq[copy_from_local_mem#]
 | |
| 
 | |
| 			alu[BUFFER_HANDLE, --, b, _buffer_handle]
 | |
| 			alu[BUFFER_START, --, b, _buffer_start]
 | |
| 			alu[BUFFER_LENGTH, --, b, _buffer_length]
 | |
| 			br[sync_state_done#]
 | |
| 
 | |
| 		copy_from_local_mem#:
 | |
| 			alu[_buffer_handle, --, b, BUFFER_HANDLE]
 | |
| 			alu[_buffer_start, --, b, BUFFER_START]
 | |
| 			alu[_buffer_length, --, b, BUFFER_LENGTH]
 | |
| 
 | |
| 		sync_state_done#:
 | |
| 		.end
 | |
| 
 | |
| #if 0
 | |
| 		/*
 | |
| 		 * Debug buffer state management.
 | |
| 		 */
 | |
| 		.begin
 | |
| 			.reg temp
 | |
| 
 | |
| 			alu[temp, 1, and, $rsw0, >>14]
 | |
| 			beq[no_poison#]
 | |
| 			immed[BUFFER_HANDLE, 0xdead]
 | |
| 			immed[BUFFER_START, 0xdead]
 | |
| 			immed[BUFFER_LENGTH, 0xdead]
 | |
| 		no_poison#:
 | |
| 
 | |
| 			immed[temp, 0xdead]
 | |
| 			alu[--, _buffer_handle, -, temp]
 | |
| 			beq[state_corrupted#]
 | |
| 			alu[--, _buffer_start, -, temp]
 | |
| 			beq[state_corrupted#]
 | |
| 			alu[--, _buffer_length, -, temp]
 | |
| 			beq[state_corrupted#]
 | |
| 		.end
 | |
| #endif
 | |
| 
 | |
| 		/*
 | |
| 		 * Check buffer length.
 | |
| 		 */
 | |
| 		.begin
 | |
| 			alu[--, _buffer_length, -, _packet_length]
 | |
| 			blo[buffer_overflow#]
 | |
| 		.end
 | |
| 
 | |
| 		/*
 | |
| 		 * Copy the mpacket and give back the RBUF element.
 | |
| 		 */
 | |
| 		.begin
 | |
| 			.reg element
 | |
| 			.reg xfer_size
 | |
| 			.reg temp
 | |
| 			.sig copy_sig
 | |
| 
 | |
| 			alu_shf[element, 0x7f, and, $rsw0, >>24]
 | |
| 			alu_shf[xfer_size, 0xff, and, $rsw0, >>16]
 | |
| 
 | |
| 			alu[xfer_size, xfer_size, -, 1]
 | |
| 			alu_shf[xfer_size, 0x10, or, xfer_size, >>3]
 | |
| 			alu_shf[temp, 0x10, or, xfer_size, <<21]
 | |
| 			alu_shf[temp, temp, or, element, <<11]
 | |
| 			alu_shf[--, temp, or, 1, <<18]
 | |
| 
 | |
| 			dram[rbuf_rd, --, _buffer_start, buffer_offset, max_8],
 | |
| 						indirect_ref, sig_done[copy_sig]
 | |
| 			ctx_arb[copy_sig]
 | |
| 
 | |
| 			alu[temp, RBUF_ELEMENT_DONE, or, element, <<16]
 | |
| 			msf[fast_wr, --, temp, 0]
 | |
| 		.end
 | |
| 
 | |
| 		/*
 | |
| 		 * If EOP, write back the packet descriptor.
 | |
| 		 */
 | |
| 		.begin
 | |
| 			.reg write $stemp $stemp2
 | |
| 			.xfer_order $stemp $stemp2
 | |
| 			.sig zzz
 | |
| 
 | |
| 			alu_shf[--, 1, and, $rsw0, >>14]
 | |
| 			beq[no_writeback#]
 | |
| 
 | |
| 			alu[$stemp, $rsw0, and, 0x1f]
 | |
| 			alu[$stemp2, --, b, _packet_length]
 | |
| 			sram[write, $stemp, _buffer_handle, 8, 2], ctx_swap[zzz]
 | |
| 
 | |
| 		no_writeback#:
 | |
| 		.end
 | |
| 
 | |
| 		/*
 | |
| 		 * Resynchronise.
 | |
| 		 */
 | |
| 		.begin
 | |
| 			ctx_arb[sig3]
 | |
| 			local_csr_wr[SAME_ME_SIGNAL, (0x80 | (&sig3 << 3))]
 | |
| 		.end
 | |
| 
 | |
| 		/*
 | |
| 		 * If EOP, put the buffer back onto the scratch ring.
 | |
| 		 */
 | |
| 		.begin
 | |
| 			.reg write $stemp
 | |
| 			.sig zzz
 | |
| 
 | |
| 			br_inp_state[SCR_Ring1_Status, rx_done_ring_overflow#]
 | |
| 
 | |
| 			alu_shf[--, 1, and, $rsw0, >>14]
 | |
| 			beq[mpacket_receive_loop#]
 | |
| 
 | |
| 			alu[--, 1, and, $rsw0, >>10]
 | |
| 			bne[rxerr#]
 | |
| 
 | |
| 			alu[$stemp, --, b, _buffer_handle]
 | |
| 			scratch[put, $stemp, zero, 4, 1], ctx_swap[zzz]
 | |
| 			cap[fast_wr, 0, XSCALE_INT_A]
 | |
| 			br[mpacket_receive_loop#]
 | |
| 
 | |
| 		rxerr#:
 | |
| 			alu[$stemp, --, b, _buffer_handle]
 | |
| 			scratch[put, $stemp, zero, 0, 1], ctx_swap[zzz]
 | |
| 			br[mpacket_receive_loop#]
 | |
| 		.end
 | |
| 	.end
 | |
| 
 | |
| 
 | |
| abort_rswerr#:
 | |
| 	halt
 | |
| 
 | |
| abort_proterr#:
 | |
| 	halt
 | |
| 
 | |
| state_corrupted#:
 | |
| 	halt
 | |
| 
 | |
| buffer_overflow#:
 | |
| 	halt
 | |
| 
 | |
| rx_done_ring_overflow#:
 | |
| 	halt
 | |
| 
 | |
| 
 |