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cadence_gem.c
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/*
* QEMU Cadence GEM emulation
*
* Copyright (c) 2011 Xilinx, Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "qemu/osdep.h"
#include <zlib.h> /* For crc32 */
#include "hw/irq.h"
#include "hw/net/cadence_gem.h"
#include "hw/qdev-properties.h"
#include "migration/vmstate.h"
#include "qapi/error.h"
#include "qemu/log.h"
#include "qemu/module.h"
#include "sysemu/dma.h"
#include "net/checksum.h"
#include "net/eth.h"
#define CADENCE_GEM_ERR_DEBUG 0
#define DB_PRINT(...) do {\
if (CADENCE_GEM_ERR_DEBUG) { \
qemu_log(": %s: ", __func__); \
qemu_log(__VA_ARGS__); \
} \
} while (0)
#define GEM_NWCTRL (0x00000000 / 4) /* Network Control reg */
#define GEM_NWCFG (0x00000004 / 4) /* Network Config reg */
#define GEM_NWSTATUS (0x00000008 / 4) /* Network Status reg */
#define GEM_USERIO (0x0000000C / 4) /* User IO reg */
#define GEM_DMACFG (0x00000010 / 4) /* DMA Control reg */
#define GEM_TXSTATUS (0x00000014 / 4) /* TX Status reg */
#define GEM_RXQBASE (0x00000018 / 4) /* RX Q Base address reg */
#define GEM_TXQBASE (0x0000001C / 4) /* TX Q Base address reg */
#define GEM_RXSTATUS (0x00000020 / 4) /* RX Status reg */
#define GEM_ISR (0x00000024 / 4) /* Interrupt Status reg */
#define GEM_IER (0x00000028 / 4) /* Interrupt Enable reg */
#define GEM_IDR (0x0000002C / 4) /* Interrupt Disable reg */
#define GEM_IMR (0x00000030 / 4) /* Interrupt Mask reg */
#define GEM_PHYMNTNC (0x00000034 / 4) /* Phy Maintenance reg */
#define GEM_RXPAUSE (0x00000038 / 4) /* RX Pause Time reg */
#define GEM_TXPAUSE (0x0000003C / 4) /* TX Pause Time reg */
#define GEM_TXPARTIALSF (0x00000040 / 4) /* TX Partial Store and Forward */
#define GEM_RXPARTIALSF (0x00000044 / 4) /* RX Partial Store and Forward */
#define GEM_JUMBO_MAX_LEN (0x00000048 / 4) /* Max Jumbo Frame Size */
#define GEM_HASHLO (0x00000080 / 4) /* Hash Low address reg */
#define GEM_HASHHI (0x00000084 / 4) /* Hash High address reg */
#define GEM_SPADDR1LO (0x00000088 / 4) /* Specific addr 1 low reg */
#define GEM_SPADDR1HI (0x0000008C / 4) /* Specific addr 1 high reg */
#define GEM_SPADDR2LO (0x00000090 / 4) /* Specific addr 2 low reg */
#define GEM_SPADDR2HI (0x00000094 / 4) /* Specific addr 2 high reg */
#define GEM_SPADDR3LO (0x00000098 / 4) /* Specific addr 3 low reg */
#define GEM_SPADDR3HI (0x0000009C / 4) /* Specific addr 3 high reg */
#define GEM_SPADDR4LO (0x000000A0 / 4) /* Specific addr 4 low reg */
#define GEM_SPADDR4HI (0x000000A4 / 4) /* Specific addr 4 high reg */
#define GEM_TIDMATCH1 (0x000000A8 / 4) /* Type ID1 Match reg */
#define GEM_TIDMATCH2 (0x000000AC / 4) /* Type ID2 Match reg */
#define GEM_TIDMATCH3 (0x000000B0 / 4) /* Type ID3 Match reg */
#define GEM_TIDMATCH4 (0x000000B4 / 4) /* Type ID4 Match reg */
#define GEM_WOLAN (0x000000B8 / 4) /* Wake on LAN reg */
#define GEM_IPGSTRETCH (0x000000BC / 4) /* IPG Stretch reg */
#define GEM_SVLAN (0x000000C0 / 4) /* Stacked VLAN reg */
#define GEM_MODID (0x000000FC / 4) /* Module ID reg */
#define GEM_OCTTXLO (0x00000100 / 4) /* Octects transmitted Low reg */
#define GEM_OCTTXHI (0x00000104 / 4) /* Octects transmitted High reg */
#define GEM_TXCNT (0x00000108 / 4) /* Error-free Frames transmitted */
#define GEM_TXBCNT (0x0000010C / 4) /* Error-free Broadcast Frames */
#define GEM_TXMCNT (0x00000110 / 4) /* Error-free Multicast Frame */
#define GEM_TXPAUSECNT (0x00000114 / 4) /* Pause Frames Transmitted */
#define GEM_TX64CNT (0x00000118 / 4) /* Error-free 64 TX */
#define GEM_TX65CNT (0x0000011C / 4) /* Error-free 65-127 TX */
#define GEM_TX128CNT (0x00000120 / 4) /* Error-free 128-255 TX */
#define GEM_TX256CNT (0x00000124 / 4) /* Error-free 256-511 */
#define GEM_TX512CNT (0x00000128 / 4) /* Error-free 512-1023 TX */
#define GEM_TX1024CNT (0x0000012C / 4) /* Error-free 1024-1518 TX */
#define GEM_TX1519CNT (0x00000130 / 4) /* Error-free larger than 1519 TX */
#define GEM_TXURUNCNT (0x00000134 / 4) /* TX under run error counter */
#define GEM_SINGLECOLLCNT (0x00000138 / 4) /* Single Collision Frames */
#define GEM_MULTCOLLCNT (0x0000013C / 4) /* Multiple Collision Frames */
#define GEM_EXCESSCOLLCNT (0x00000140 / 4) /* Excessive Collision Frames */
#define GEM_LATECOLLCNT (0x00000144 / 4) /* Late Collision Frames */
#define GEM_DEFERTXCNT (0x00000148 / 4) /* Deferred Transmission Frames */
#define GEM_CSENSECNT (0x0000014C / 4) /* Carrier Sense Error Counter */
#define GEM_OCTRXLO (0x00000150 / 4) /* Octects Received register Low */
#define GEM_OCTRXHI (0x00000154 / 4) /* Octects Received register High */
#define GEM_RXCNT (0x00000158 / 4) /* Error-free Frames Received */
#define GEM_RXBROADCNT (0x0000015C / 4) /* Error-free Broadcast Frames RX */
#define GEM_RXMULTICNT (0x00000160 / 4) /* Error-free Multicast Frames RX */
#define GEM_RXPAUSECNT (0x00000164 / 4) /* Pause Frames Received Counter */
#define GEM_RX64CNT (0x00000168 / 4) /* Error-free 64 byte Frames RX */
#define GEM_RX65CNT (0x0000016C / 4) /* Error-free 65-127B Frames RX */
#define GEM_RX128CNT (0x00000170 / 4) /* Error-free 128-255B Frames RX */
#define GEM_RX256CNT (0x00000174 / 4) /* Error-free 256-512B Frames RX */
#define GEM_RX512CNT (0x00000178 / 4) /* Error-free 512-1023B Frames RX */
#define GEM_RX1024CNT (0x0000017C / 4) /* Error-free 1024-1518B Frames RX */
#define GEM_RX1519CNT (0x00000180 / 4) /* Error-free 1519-max Frames RX */
#define GEM_RXUNDERCNT (0x00000184 / 4) /* Undersize Frames Received */
#define GEM_RXOVERCNT (0x00000188 / 4) /* Oversize Frames Received */
#define GEM_RXJABCNT (0x0000018C / 4) /* Jabbers Received Counter */
#define GEM_RXFCSCNT (0x00000190 / 4) /* Frame Check seq. Error Counter */
#define GEM_RXLENERRCNT (0x00000194 / 4) /* Length Field Error Counter */
#define GEM_RXSYMERRCNT (0x00000198 / 4) /* Symbol Error Counter */
#define GEM_RXALIGNERRCNT (0x0000019C / 4) /* Alignment Error Counter */
#define GEM_RXRSCERRCNT (0x000001A0 / 4) /* Receive Resource Error Counter */
#define GEM_RXORUNCNT (0x000001A4 / 4) /* Receive Overrun Counter */
#define GEM_RXIPCSERRCNT (0x000001A8 / 4) /* IP header Checksum Err Counter */
#define GEM_RXTCPCCNT (0x000001AC / 4) /* TCP Checksum Error Counter */
#define GEM_RXUDPCCNT (0x000001B0 / 4) /* UDP Checksum Error Counter */
#define GEM_1588S (0x000001D0 / 4) /* 1588 Timer Seconds */
#define GEM_1588NS (0x000001D4 / 4) /* 1588 Timer Nanoseconds */
#define GEM_1588ADJ (0x000001D8 / 4) /* 1588 Timer Adjust */
#define GEM_1588INC (0x000001DC / 4) /* 1588 Timer Increment */
#define GEM_PTPETXS (0x000001E0 / 4) /* PTP Event Frame Transmitted (s) */
#define GEM_PTPETXNS (0x000001E4 / 4) /*
* PTP Event Frame Transmitted (ns)
*/
#define GEM_PTPERXS (0x000001E8 / 4) /* PTP Event Frame Received (s) */
#define GEM_PTPERXNS (0x000001EC / 4) /* PTP Event Frame Received (ns) */
#define GEM_PTPPTXS (0x000001E0 / 4) /* PTP Peer Frame Transmitted (s) */
#define GEM_PTPPTXNS (0x000001E4 / 4) /* PTP Peer Frame Transmitted (ns) */
#define GEM_PTPPRXS (0x000001E8 / 4) /* PTP Peer Frame Received (s) */
#define GEM_PTPPRXNS (0x000001EC / 4) /* PTP Peer Frame Received (ns) */
/* Design Configuration Registers */
#define GEM_DESCONF (0x00000280 / 4)
#define GEM_DESCONF2 (0x00000284 / 4)
#define GEM_DESCONF3 (0x00000288 / 4)
#define GEM_DESCONF4 (0x0000028C / 4)
#define GEM_DESCONF5 (0x00000290 / 4)
#define GEM_DESCONF6 (0x00000294 / 4)
#define GEM_DESCONF6_64B_MASK (1U << 23)
#define GEM_DESCONF7 (0x00000298 / 4)
#define GEM_INT_Q1_STATUS (0x00000400 / 4)
#define GEM_INT_Q1_MASK (0x00000640 / 4)
#define GEM_TRANSMIT_Q1_PTR (0x00000440 / 4)
#define GEM_TRANSMIT_Q7_PTR (GEM_TRANSMIT_Q1_PTR + 6)
#define GEM_RECEIVE_Q1_PTR (0x00000480 / 4)
#define GEM_RECEIVE_Q7_PTR (GEM_RECEIVE_Q1_PTR + 6)
#define GEM_TBQPH (0x000004C8 / 4)
#define GEM_RBQPH (0x000004D4 / 4)
#define GEM_INT_Q1_ENABLE (0x00000600 / 4)
#define GEM_INT_Q7_ENABLE (GEM_INT_Q1_ENABLE + 6)
#define GEM_INT_Q1_DISABLE (0x00000620 / 4)
#define GEM_INT_Q7_DISABLE (GEM_INT_Q1_DISABLE + 6)
#define GEM_INT_Q1_MASK (0x00000640 / 4)
#define GEM_INT_Q7_MASK (GEM_INT_Q1_MASK + 6)
#define GEM_SCREENING_TYPE1_REGISTER_0 (0x00000500 / 4)
#define GEM_ST1R_UDP_PORT_MATCH_ENABLE (1 << 29)
#define GEM_ST1R_DSTC_ENABLE (1 << 28)
#define GEM_ST1R_UDP_PORT_MATCH_SHIFT (12)
#define GEM_ST1R_UDP_PORT_MATCH_WIDTH (27 - GEM_ST1R_UDP_PORT_MATCH_SHIFT + 1)
#define GEM_ST1R_DSTC_MATCH_SHIFT (4)
#define GEM_ST1R_DSTC_MATCH_WIDTH (11 - GEM_ST1R_DSTC_MATCH_SHIFT + 1)
#define GEM_ST1R_QUEUE_SHIFT (0)
#define GEM_ST1R_QUEUE_WIDTH (3 - GEM_ST1R_QUEUE_SHIFT + 1)
#define GEM_SCREENING_TYPE2_REGISTER_0 (0x00000540 / 4)
#define GEM_ST2R_COMPARE_A_ENABLE (1 << 18)
#define GEM_ST2R_COMPARE_A_SHIFT (13)
#define GEM_ST2R_COMPARE_WIDTH (17 - GEM_ST2R_COMPARE_A_SHIFT + 1)
#define GEM_ST2R_ETHERTYPE_ENABLE (1 << 12)
#define GEM_ST2R_ETHERTYPE_INDEX_SHIFT (9)
#define GEM_ST2R_ETHERTYPE_INDEX_WIDTH (11 - GEM_ST2R_ETHERTYPE_INDEX_SHIFT \
+ 1)
#define GEM_ST2R_QUEUE_SHIFT (0)
#define GEM_ST2R_QUEUE_WIDTH (3 - GEM_ST2R_QUEUE_SHIFT + 1)
#define GEM_SCREENING_TYPE2_ETHERTYPE_REG_0 (0x000006e0 / 4)
#define GEM_TYPE2_COMPARE_0_WORD_0 (0x00000700 / 4)
#define GEM_T2CW1_COMPARE_OFFSET_SHIFT (7)
#define GEM_T2CW1_COMPARE_OFFSET_WIDTH (8 - GEM_T2CW1_COMPARE_OFFSET_SHIFT + 1)
#define GEM_T2CW1_OFFSET_VALUE_SHIFT (0)
#define GEM_T2CW1_OFFSET_VALUE_WIDTH (6 - GEM_T2CW1_OFFSET_VALUE_SHIFT + 1)
/*****************************************/
#define GEM_NWCTRL_TXSTART 0x00000200 /* Transmit Enable */
#define GEM_NWCTRL_TXENA 0x00000008 /* Transmit Enable */
#define GEM_NWCTRL_RXENA 0x00000004 /* Receive Enable */
#define GEM_NWCTRL_LOCALLOOP 0x00000002 /* Local Loopback */
#define GEM_NWCFG_STRIP_FCS 0x00020000 /* Strip FCS field */
#define GEM_NWCFG_LERR_DISC 0x00010000 /* Discard RX frames with len err */
#define GEM_NWCFG_BUFF_OFST_M 0x0000C000 /* Receive buffer offset mask */
#define GEM_NWCFG_BUFF_OFST_S 14 /* Receive buffer offset shift */
#define GEM_NWCFG_RCV_1538 0x00000100 /* Receive 1538 bytes frame */
#define GEM_NWCFG_UCAST_HASH 0x00000080 /* accept unicast if hash match */
#define GEM_NWCFG_MCAST_HASH 0x00000040 /* accept multicast if hash match */
#define GEM_NWCFG_BCAST_REJ 0x00000020 /* Reject broadcast packets */
#define GEM_NWCFG_PROMISC 0x00000010 /* Accept all packets */
#define GEM_NWCFG_JUMBO_FRAME 0x00000008 /* Jumbo Frames enable */
#define GEM_DMACFG_ADDR_64B (1U << 30)
#define GEM_DMACFG_TX_BD_EXT (1U << 29)
#define GEM_DMACFG_RX_BD_EXT (1U << 28)
#define GEM_DMACFG_RBUFSZ_M 0x00FF0000 /* DMA RX Buffer Size mask */
#define GEM_DMACFG_RBUFSZ_S 16 /* DMA RX Buffer Size shift */
#define GEM_DMACFG_RBUFSZ_MUL 64 /* DMA RX Buffer Size multiplier */
#define GEM_DMACFG_TXCSUM_OFFL 0x00000800 /* Transmit checksum offload */
#define GEM_TXSTATUS_TXCMPL 0x00000020 /* Transmit Complete */
#define GEM_TXSTATUS_USED 0x00000001 /* sw owned descriptor encountered */
#define GEM_RXSTATUS_FRMRCVD 0x00000002 /* Frame received */
#define GEM_RXSTATUS_NOBUF 0x00000001 /* Buffer unavailable */
/* GEM_ISR GEM_IER GEM_IDR GEM_IMR */
#define GEM_INT_TXCMPL 0x00000080 /* Transmit Complete */
#define GEM_INT_AMBA_ERR 0x00000040
#define GEM_INT_TXUSED 0x00000008
#define GEM_INT_RXUSED 0x00000004
#define GEM_INT_RXCMPL 0x00000002
#define GEM_PHYMNTNC_OP_R 0x20000000 /* read operation */
#define GEM_PHYMNTNC_OP_W 0x10000000 /* write operation */
#define GEM_PHYMNTNC_ADDR 0x0F800000 /* Address bits */
#define GEM_PHYMNTNC_ADDR_SHFT 23
#define GEM_PHYMNTNC_REG 0x007C0000 /* register bits */
#define GEM_PHYMNTNC_REG_SHIFT 18
/* Marvell PHY definitions */
#define BOARD_PHY_ADDRESS 0 /* PHY address we will emulate a device at */
#define PHY_REG_CONTROL 0
#define PHY_REG_STATUS 1
#define PHY_REG_PHYID1 2
#define PHY_REG_PHYID2 3
#define PHY_REG_ANEGADV 4
#define PHY_REG_LINKPABIL 5
#define PHY_REG_ANEGEXP 6
#define PHY_REG_NEXTP 7
#define PHY_REG_LINKPNEXTP 8
#define PHY_REG_100BTCTRL 9
#define PHY_REG_1000BTSTAT 10
#define PHY_REG_EXTSTAT 15
#define PHY_REG_PHYSPCFC_CTL 16
#define PHY_REG_PHYSPCFC_ST 17
#define PHY_REG_INT_EN 18
#define PHY_REG_INT_ST 19
#define PHY_REG_EXT_PHYSPCFC_CTL 20
#define PHY_REG_RXERR 21
#define PHY_REG_EACD 22
#define PHY_REG_LED 24
#define PHY_REG_LED_OVRD 25
#define PHY_REG_EXT_PHYSPCFC_CTL2 26
#define PHY_REG_EXT_PHYSPCFC_ST 27
#define PHY_REG_CABLE_DIAG 28
#define PHY_REG_CONTROL_RST 0x8000
#define PHY_REG_CONTROL_LOOP 0x4000
#define PHY_REG_CONTROL_ANEG 0x1000
#define PHY_REG_CONTROL_ANRESTART 0x0200
#define PHY_REG_STATUS_LINK 0x0004
#define PHY_REG_STATUS_ANEGCMPL 0x0020
#define PHY_REG_INT_ST_ANEGCMPL 0x0800
#define PHY_REG_INT_ST_LINKC 0x0400
#define PHY_REG_INT_ST_ENERGY 0x0010
/***********************************************************************/
#define GEM_RX_REJECT (-1)
#define GEM_RX_PROMISCUOUS_ACCEPT (-2)
#define GEM_RX_BROADCAST_ACCEPT (-3)
#define GEM_RX_MULTICAST_HASH_ACCEPT (-4)
#define GEM_RX_UNICAST_HASH_ACCEPT (-5)
#define GEM_RX_SAR_ACCEPT 0
/***********************************************************************/
#define DESC_1_USED 0x80000000
#define DESC_1_LENGTH 0x00001FFF
#define DESC_1_TX_WRAP 0x40000000
#define DESC_1_TX_LAST 0x00008000
#define DESC_0_RX_WRAP 0x00000002
#define DESC_0_RX_OWNERSHIP 0x00000001
#define R_DESC_1_RX_SAR_SHIFT 25
#define R_DESC_1_RX_SAR_LENGTH 2
#define R_DESC_1_RX_SAR_MATCH (1 << 27)
#define R_DESC_1_RX_UNICAST_HASH (1 << 29)
#define R_DESC_1_RX_MULTICAST_HASH (1 << 30)
#define R_DESC_1_RX_BROADCAST (1 << 31)
#define DESC_1_RX_SOF 0x00004000
#define DESC_1_RX_EOF 0x00008000
#define GEM_MODID_VALUE 0x00020118
static inline uint64_t tx_desc_get_buffer(CadenceGEMState *s, uint32_t *desc)
{
uint64_t ret = desc[0];
if (s->regs[GEM_DMACFG] & GEM_DMACFG_ADDR_64B) {
ret |= (uint64_t)desc[2] << 32;
}
return ret;
}
static inline unsigned tx_desc_get_used(uint32_t *desc)
{
return (desc[1] & DESC_1_USED) ? 1 : 0;
}
static inline void tx_desc_set_used(uint32_t *desc)
{
desc[1] |= DESC_1_USED;
}
static inline unsigned tx_desc_get_wrap(uint32_t *desc)
{
return (desc[1] & DESC_1_TX_WRAP) ? 1 : 0;
}
static inline unsigned tx_desc_get_last(uint32_t *desc)
{
return (desc[1] & DESC_1_TX_LAST) ? 1 : 0;
}
static inline unsigned tx_desc_get_length(uint32_t *desc)
{
return desc[1] & DESC_1_LENGTH;
}
static inline void print_gem_tx_desc(uint32_t *desc, uint8_t queue)
{
DB_PRINT("TXDESC (queue %" PRId8 "):\n", queue);
DB_PRINT("bufaddr: 0x%08x\n", *desc);
DB_PRINT("used_hw: %d\n", tx_desc_get_used(desc));
DB_PRINT("wrap: %d\n", tx_desc_get_wrap(desc));
DB_PRINT("last: %d\n", tx_desc_get_last(desc));
DB_PRINT("length: %d\n", tx_desc_get_length(desc));
}
static inline uint64_t rx_desc_get_buffer(CadenceGEMState *s, uint32_t *desc)
{
uint64_t ret = desc[0] & ~0x3UL;
if (s->regs[GEM_DMACFG] & GEM_DMACFG_ADDR_64B) {
ret |= (uint64_t)desc[2] << 32;
}
return ret;
}
static inline int gem_get_desc_len(CadenceGEMState *s, bool rx_n_tx)
{
int ret = 2;
if (s->regs[GEM_DMACFG] & GEM_DMACFG_ADDR_64B) {
ret += 2;
}
if (s->regs[GEM_DMACFG] & (rx_n_tx ? GEM_DMACFG_RX_BD_EXT
: GEM_DMACFG_TX_BD_EXT)) {
ret += 2;
}
assert(ret <= DESC_MAX_NUM_WORDS);
return ret;
}
static inline unsigned rx_desc_get_wrap(uint32_t *desc)
{
return desc[0] & DESC_0_RX_WRAP ? 1 : 0;
}
static inline unsigned rx_desc_get_ownership(uint32_t *desc)
{
return desc[0] & DESC_0_RX_OWNERSHIP ? 1 : 0;
}
static inline void rx_desc_set_ownership(uint32_t *desc)
{
desc[0] |= DESC_0_RX_OWNERSHIP;
}
static inline void rx_desc_set_sof(uint32_t *desc)
{
desc[1] |= DESC_1_RX_SOF;
}
static inline void rx_desc_clear_control(uint32_t *desc)
{
desc[1] = 0;
}
static inline void rx_desc_set_eof(uint32_t *desc)
{
desc[1] |= DESC_1_RX_EOF;
}
static inline void rx_desc_set_length(uint32_t *desc, unsigned len)
{
desc[1] &= ~DESC_1_LENGTH;
desc[1] |= len;
}
static inline void rx_desc_set_broadcast(uint32_t *desc)
{
desc[1] |= R_DESC_1_RX_BROADCAST;
}
static inline void rx_desc_set_unicast_hash(uint32_t *desc)
{
desc[1] |= R_DESC_1_RX_UNICAST_HASH;
}
static inline void rx_desc_set_multicast_hash(uint32_t *desc)
{
desc[1] |= R_DESC_1_RX_MULTICAST_HASH;
}
static inline void rx_desc_set_sar(uint32_t *desc, int sar_idx)
{
desc[1] = deposit32(desc[1], R_DESC_1_RX_SAR_SHIFT, R_DESC_1_RX_SAR_LENGTH,
sar_idx);
desc[1] |= R_DESC_1_RX_SAR_MATCH;
}
/* The broadcast MAC address: 0xFFFFFFFFFFFF */
static const uint8_t broadcast_addr[] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
static uint32_t gem_get_max_buf_len(CadenceGEMState *s, bool tx)
{
uint32_t size;
if (s->regs[GEM_NWCFG] & GEM_NWCFG_JUMBO_FRAME) {
size = s->regs[GEM_JUMBO_MAX_LEN];
if (size > s->jumbo_max_len) {
size = s->jumbo_max_len;
qemu_log_mask(LOG_GUEST_ERROR, "GEM_JUMBO_MAX_LEN reg cannot be"
" greater than 0x%" PRIx32 "\n", s->jumbo_max_len);
}
} else if (tx) {
size = 1518;
} else {
size = s->regs[GEM_NWCFG] & GEM_NWCFG_RCV_1538 ? 1538 : 1518;
}
return size;
}
static void gem_set_isr(CadenceGEMState *s, int q, uint32_t flag)
{
if (q == 0) {
s->regs[GEM_ISR] |= flag & ~(s->regs[GEM_IMR]);
} else {
s->regs[GEM_INT_Q1_STATUS + q - 1] |= flag &
~(s->regs[GEM_INT_Q1_MASK + q - 1]);
}
}
/*
* gem_init_register_masks:
* One time initialization.
* Set masks to identify which register bits have magical clear properties
*/
static void gem_init_register_masks(CadenceGEMState *s)
{
unsigned int i;
/* Mask of register bits which are read only */
memset(&s->regs_ro[0], 0, sizeof(s->regs_ro));
s->regs_ro[GEM_NWCTRL] = 0xFFF80000;
s->regs_ro[GEM_NWSTATUS] = 0xFFFFFFFF;
s->regs_ro[GEM_DMACFG] = 0x8E00F000;
s->regs_ro[GEM_TXSTATUS] = 0xFFFFFE08;
s->regs_ro[GEM_RXQBASE] = 0x00000003;
s->regs_ro[GEM_TXQBASE] = 0x00000003;
s->regs_ro[GEM_RXSTATUS] = 0xFFFFFFF0;
s->regs_ro[GEM_ISR] = 0xFFFFFFFF;
s->regs_ro[GEM_IMR] = 0xFFFFFFFF;
s->regs_ro[GEM_MODID] = 0xFFFFFFFF;
for (i = 0; i < s->num_priority_queues; i++) {
s->regs_ro[GEM_INT_Q1_STATUS + i] = 0xFFFFFFFF;
s->regs_ro[GEM_INT_Q1_ENABLE + i] = 0xFFFFF319;
s->regs_ro[GEM_INT_Q1_DISABLE + i] = 0xFFFFF319;
s->regs_ro[GEM_INT_Q1_MASK + i] = 0xFFFFFFFF;
}
/* Mask of register bits which are clear on read */
memset(&s->regs_rtc[0], 0, sizeof(s->regs_rtc));
s->regs_rtc[GEM_ISR] = 0xFFFFFFFF;
for (i = 0; i < s->num_priority_queues; i++) {
s->regs_rtc[GEM_INT_Q1_STATUS + i] = 0x00000CE6;
}
/* Mask of register bits which are write 1 to clear */
memset(&s->regs_w1c[0], 0, sizeof(s->regs_w1c));
s->regs_w1c[GEM_TXSTATUS] = 0x000001F7;
s->regs_w1c[GEM_RXSTATUS] = 0x0000000F;
/* Mask of register bits which are write only */
memset(&s->regs_wo[0], 0, sizeof(s->regs_wo));
s->regs_wo[GEM_NWCTRL] = 0x00073E60;
s->regs_wo[GEM_IER] = 0x07FFFFFF;
s->regs_wo[GEM_IDR] = 0x07FFFFFF;
for (i = 0; i < s->num_priority_queues; i++) {
s->regs_wo[GEM_INT_Q1_ENABLE + i] = 0x00000CE6;
s->regs_wo[GEM_INT_Q1_DISABLE + i] = 0x00000CE6;
}
}
/*
* phy_update_link:
* Make the emulated PHY link state match the QEMU "interface" state.
*/
static void phy_update_link(CadenceGEMState *s)
{
DB_PRINT("down %d\n", qemu_get_queue(s->nic)->link_down);
/* Autonegotiation status mirrors link status. */
if (qemu_get_queue(s->nic)->link_down) {
s->phy_regs[PHY_REG_STATUS] &= ~(PHY_REG_STATUS_ANEGCMPL |
PHY_REG_STATUS_LINK);
s->phy_regs[PHY_REG_INT_ST] |= PHY_REG_INT_ST_LINKC;
} else {
s->phy_regs[PHY_REG_STATUS] |= (PHY_REG_STATUS_ANEGCMPL |
PHY_REG_STATUS_LINK);
s->phy_regs[PHY_REG_INT_ST] |= (PHY_REG_INT_ST_LINKC |
PHY_REG_INT_ST_ANEGCMPL |
PHY_REG_INT_ST_ENERGY);
}
}
static bool gem_can_receive(NetClientState *nc)
{
CadenceGEMState *s;
int i;
s = qemu_get_nic_opaque(nc);
/* Do nothing if receive is not enabled. */
if (!(s->regs[GEM_NWCTRL] & GEM_NWCTRL_RXENA)) {
if (s->can_rx_state != 1) {
s->can_rx_state = 1;
DB_PRINT("can't receive - no enable\n");
}
return false;
}
for (i = 0; i < s->num_priority_queues; i++) {
if (rx_desc_get_ownership(s->rx_desc[i]) != 1) {
break;
}
};
if (i == s->num_priority_queues) {
if (s->can_rx_state != 2) {
s->can_rx_state = 2;
DB_PRINT("can't receive - all the buffer descriptors are busy\n");
}
return false;
}
if (s->can_rx_state != 0) {
s->can_rx_state = 0;
DB_PRINT("can receive\n");
}
return true;
}
/*
* gem_update_int_status:
* Raise or lower interrupt based on current status.
*/
static void gem_update_int_status(CadenceGEMState *s)
{
int i;
qemu_set_irq(s->irq[0], !!s->regs[GEM_ISR]);
for (i = 1; i < s->num_priority_queues; ++i) {
qemu_set_irq(s->irq[i], !!s->regs[GEM_INT_Q1_STATUS + i - 1]);
}
}
/*
* gem_receive_updatestats:
* Increment receive statistics.
*/
static void gem_receive_updatestats(CadenceGEMState *s, const uint8_t *packet,
unsigned bytes)
{
uint64_t octets;
/* Total octets (bytes) received */
octets = ((uint64_t)(s->regs[GEM_OCTRXLO]) << 32) |
s->regs[GEM_OCTRXHI];
octets += bytes;
s->regs[GEM_OCTRXLO] = octets >> 32;
s->regs[GEM_OCTRXHI] = octets;
/* Error-free Frames received */
s->regs[GEM_RXCNT]++;
/* Error-free Broadcast Frames counter */
if (!memcmp(packet, broadcast_addr, 6)) {
s->regs[GEM_RXBROADCNT]++;
}
/* Error-free Multicast Frames counter */
if (packet[0] == 0x01) {
s->regs[GEM_RXMULTICNT]++;
}
if (bytes <= 64) {
s->regs[GEM_RX64CNT]++;
} else if (bytes <= 127) {
s->regs[GEM_RX65CNT]++;
} else if (bytes <= 255) {
s->regs[GEM_RX128CNT]++;
} else if (bytes <= 511) {
s->regs[GEM_RX256CNT]++;
} else if (bytes <= 1023) {
s->regs[GEM_RX512CNT]++;
} else if (bytes <= 1518) {
s->regs[GEM_RX1024CNT]++;
} else {
s->regs[GEM_RX1519CNT]++;
}
}
/*
* Get the MAC Address bit from the specified position
*/
static unsigned get_bit(const uint8_t *mac, unsigned bit)
{
unsigned byte;
byte = mac[bit / 8];
byte >>= (bit & 0x7);
byte &= 1;
return byte;
}
/*
* Calculate a GEM MAC Address hash index
*/
static unsigned calc_mac_hash(const uint8_t *mac)
{
int index_bit, mac_bit;
unsigned hash_index;
hash_index = 0;
mac_bit = 5;
for (index_bit = 5; index_bit >= 0; index_bit--) {
hash_index |= (get_bit(mac, mac_bit) ^
get_bit(mac, mac_bit + 6) ^
get_bit(mac, mac_bit + 12) ^
get_bit(mac, mac_bit + 18) ^
get_bit(mac, mac_bit + 24) ^
get_bit(mac, mac_bit + 30) ^
get_bit(mac, mac_bit + 36) ^
get_bit(mac, mac_bit + 42)) << index_bit;
mac_bit--;
}
return hash_index;
}
/*
* gem_mac_address_filter:
* Accept or reject this destination address?
* Returns:
* GEM_RX_REJECT: reject
* >= 0: Specific address accept (which matched SAR is returned)
* others for various other modes of accept:
* GEM_RM_PROMISCUOUS_ACCEPT, GEM_RX_BROADCAST_ACCEPT,
* GEM_RX_MULTICAST_HASH_ACCEPT or GEM_RX_UNICAST_HASH_ACCEPT
*/
static int gem_mac_address_filter(CadenceGEMState *s, const uint8_t *packet)
{
uint8_t *gem_spaddr;
int i, is_mc;
/* Promiscuous mode? */
if (s->regs[GEM_NWCFG] & GEM_NWCFG_PROMISC) {
return GEM_RX_PROMISCUOUS_ACCEPT;
}
if (!memcmp(packet, broadcast_addr, 6)) {
/* Reject broadcast packets? */
if (s->regs[GEM_NWCFG] & GEM_NWCFG_BCAST_REJ) {
return GEM_RX_REJECT;
}
return GEM_RX_BROADCAST_ACCEPT;
}
/* Accept packets -w- hash match? */
is_mc = is_multicast_ether_addr(packet);
if ((is_mc && (s->regs[GEM_NWCFG] & GEM_NWCFG_MCAST_HASH)) ||
(!is_mc && (s->regs[GEM_NWCFG] & GEM_NWCFG_UCAST_HASH))) {
uint64_t buckets;
unsigned hash_index;
hash_index = calc_mac_hash(packet);
buckets = ((uint64_t)s->regs[GEM_HASHHI] << 32) | s->regs[GEM_HASHLO];
if ((buckets >> hash_index) & 1) {
return is_mc ? GEM_RX_MULTICAST_HASH_ACCEPT
: GEM_RX_UNICAST_HASH_ACCEPT;
}
}
/* Check all 4 specific addresses */
gem_spaddr = (uint8_t *)&(s->regs[GEM_SPADDR1LO]);
for (i = 3; i >= 0; i--) {
if (s->sar_active[i] && !memcmp(packet, gem_spaddr + 8 * i, 6)) {
return GEM_RX_SAR_ACCEPT + i;
}
}
/* No address match; reject the packet */
return GEM_RX_REJECT;
}
/* Figure out which queue the received data should be sent to */
static int get_queue_from_screen(CadenceGEMState *s, uint8_t *rxbuf_ptr,
unsigned rxbufsize)
{
uint32_t reg;
bool matched, mismatched;
int i, j;
for (i = 0; i < s->num_type1_screeners; i++) {
reg = s->regs[GEM_SCREENING_TYPE1_REGISTER_0 + i];
matched = false;
mismatched = false;
/* Screening is based on UDP Port */
if (reg & GEM_ST1R_UDP_PORT_MATCH_ENABLE) {
uint16_t udp_port = rxbuf_ptr[14 + 22] << 8 | rxbuf_ptr[14 + 23];
if (udp_port == extract32(reg, GEM_ST1R_UDP_PORT_MATCH_SHIFT,
GEM_ST1R_UDP_PORT_MATCH_WIDTH)) {
matched = true;
} else {
mismatched = true;
}
}
/* Screening is based on DS/TC */
if (reg & GEM_ST1R_DSTC_ENABLE) {
uint8_t dscp = rxbuf_ptr[14 + 1];
if (dscp == extract32(reg, GEM_ST1R_DSTC_MATCH_SHIFT,
GEM_ST1R_DSTC_MATCH_WIDTH)) {
matched = true;
} else {
mismatched = true;
}
}
if (matched && !mismatched) {
return extract32(reg, GEM_ST1R_QUEUE_SHIFT, GEM_ST1R_QUEUE_WIDTH);
}
}
for (i = 0; i < s->num_type2_screeners; i++) {
reg = s->regs[GEM_SCREENING_TYPE2_REGISTER_0 + i];
matched = false;
mismatched = false;
if (reg & GEM_ST2R_ETHERTYPE_ENABLE) {
uint16_t type = rxbuf_ptr[12] << 8 | rxbuf_ptr[13];
int et_idx = extract32(reg, GEM_ST2R_ETHERTYPE_INDEX_SHIFT,
GEM_ST2R_ETHERTYPE_INDEX_WIDTH);
if (et_idx > s->num_type2_screeners) {
qemu_log_mask(LOG_GUEST_ERROR, "Out of range ethertype "
"register index: %d\n", et_idx);
}
if (type == s->regs[GEM_SCREENING_TYPE2_ETHERTYPE_REG_0 +
et_idx]) {
matched = true;
} else {
mismatched = true;
}
}
/* Compare A, B, C */
for (j = 0; j < 3; j++) {
uint32_t cr0, cr1, mask;
uint16_t rx_cmp;
int offset;
int cr_idx = extract32(reg, GEM_ST2R_COMPARE_A_SHIFT + j * 6,
GEM_ST2R_COMPARE_WIDTH);
if (!(reg & (GEM_ST2R_COMPARE_A_ENABLE << (j * 6)))) {
continue;
}
if (cr_idx > s->num_type2_screeners) {
qemu_log_mask(LOG_GUEST_ERROR, "Out of range compare "
"register index: %d\n", cr_idx);
}
cr0 = s->regs[GEM_TYPE2_COMPARE_0_WORD_0 + cr_idx * 2];
cr1 = s->regs[GEM_TYPE2_COMPARE_0_WORD_0 + cr_idx * 2 + 1];
offset = extract32(cr1, GEM_T2CW1_OFFSET_VALUE_SHIFT,
GEM_T2CW1_OFFSET_VALUE_WIDTH);
switch (extract32(cr1, GEM_T2CW1_COMPARE_OFFSET_SHIFT,
GEM_T2CW1_COMPARE_OFFSET_WIDTH)) {
case 3: /* Skip UDP header */
qemu_log_mask(LOG_UNIMP, "TCP compare offsets"
"unimplemented - assuming UDP\n");
offset += 8;
/* Fallthrough */
case 2: /* skip the IP header */
offset += 20;
/* Fallthrough */
case 1: /* Count from after the ethertype */
offset += 14;
break;
case 0:
/* Offset from start of frame */
break;
}
rx_cmp = rxbuf_ptr[offset] << 8 | rxbuf_ptr[offset];
mask = extract32(cr0, 0, 16);
if ((rx_cmp & mask) == (extract32(cr0, 16, 16) & mask)) {
matched = true;
} else {
mismatched = true;
}
}
if (matched && !mismatched) {
return extract32(reg, GEM_ST2R_QUEUE_SHIFT, GEM_ST2R_QUEUE_WIDTH);
}
}
/* We made it here, assume it's queue 0 */
return 0;
}
static uint32_t gem_get_queue_base_addr(CadenceGEMState *s, bool tx, int q)
{
uint32_t base_addr = 0;
switch (q) {
case 0:
base_addr = s->regs[tx ? GEM_TXQBASE : GEM_RXQBASE];
break;
case 1 ... (MAX_PRIORITY_QUEUES - 1):
base_addr = s->regs[(tx ? GEM_TRANSMIT_Q1_PTR :
GEM_RECEIVE_Q1_PTR) + q - 1];
break;
default:
g_assert_not_reached();
};
return base_addr;
}
static inline uint32_t gem_get_tx_queue_base_addr(CadenceGEMState *s, int q)
{
return gem_get_queue_base_addr(s, true, q);
}
static inline uint32_t gem_get_rx_queue_base_addr(CadenceGEMState *s, int q)
{
return gem_get_queue_base_addr(s, false, q);
}
static hwaddr gem_get_desc_addr(CadenceGEMState *s, bool tx, int q)
{
hwaddr desc_addr = 0;
if (s->regs[GEM_DMACFG] & GEM_DMACFG_ADDR_64B) {
desc_addr = s->regs[tx ? GEM_TBQPH : GEM_RBQPH];
}
desc_addr <<= 32;
desc_addr |= tx ? s->tx_desc_addr[q] : s->rx_desc_addr[q];
return desc_addr;
}
static hwaddr gem_get_tx_desc_addr(CadenceGEMState *s, int q)
{
return gem_get_desc_addr(s, true, q);
}
static hwaddr gem_get_rx_desc_addr(CadenceGEMState *s, int q)
{
return gem_get_desc_addr(s, false, q);
}
static void gem_get_rx_desc(CadenceGEMState *s, int q)
{
hwaddr desc_addr = gem_get_rx_desc_addr(s, q);
DB_PRINT("read descriptor 0x%" HWADDR_PRIx "\n", desc_addr);
/* read current descriptor */
address_space_read(&s->dma_as, desc_addr, MEMTXATTRS_UNSPECIFIED,
s->rx_desc[q],
sizeof(uint32_t) * gem_get_desc_len(s, true));
/* Descriptor owned by software ? */
if (rx_desc_get_ownership(s->rx_desc[q]) == 1) {
DB_PRINT("descriptor 0x%" HWADDR_PRIx " owned by sw.\n", desc_addr);
s->regs[GEM_RXSTATUS] |= GEM_RXSTATUS_NOBUF;
gem_set_isr(s, q, GEM_INT_RXUSED);
/* Handle interrupt consequences */
gem_update_int_status(s);
}
}
/*
* gem_receive:
* Fit a packet handed to us by QEMU into the receive descriptor ring.
*/
static ssize_t gem_receive(NetClientState *nc, const uint8_t *buf, size_t size)
{
CadenceGEMState *s = qemu_get_nic_opaque(nc);
unsigned rxbufsize, bytes_to_copy;
unsigned rxbuf_offset;
uint8_t *rxbuf_ptr;
bool first_desc = true;
int maf;
int q = 0;
/* Is this destination MAC address "for us" ? */
maf = gem_mac_address_filter(s, buf);
if (maf == GEM_RX_REJECT) {
return size; /* no, drop siliently b/c it's not an error */
}
/* Discard packets with receive length error enabled ? */
if (s->regs[GEM_NWCFG] & GEM_NWCFG_LERR_DISC) {
unsigned type_len;
/* Fish the ethertype / length field out of the RX packet */
type_len = buf[12] << 8 | buf[13];
/* It is a length field, not an ethertype */
if (type_len < 0x600) {
if (size < type_len) {
/* discard */
return -1;
}
}
}
/*
* Determine configured receive buffer offset (probably 0)
*/
rxbuf_offset = (s->regs[GEM_NWCFG] & GEM_NWCFG_BUFF_OFST_M) >>
GEM_NWCFG_BUFF_OFST_S;
/* The configure size of each receive buffer. Determines how many
* buffers needed to hold this packet.
*/
rxbufsize = ((s->regs[GEM_DMACFG] & GEM_DMACFG_RBUFSZ_M) >>
GEM_DMACFG_RBUFSZ_S) * GEM_DMACFG_RBUFSZ_MUL;
bytes_to_copy = size;
/* Hardware allows a zero value here but warns against it. To avoid QEMU
* indefinite loops we enforce a minimum value here
*/
if (rxbufsize < GEM_DMACFG_RBUFSZ_MUL) {
rxbufsize = GEM_DMACFG_RBUFSZ_MUL;
}
/* Pad to minimum length. Assume FCS field is stripped, logic
* below will increment it to the real minimum of 64 when
* not FCS stripping
*/
if (size < 60) {
size = 60;