diff options
author | Jiri Kosina <jkosina@suse.cz> | 2010-04-22 20:08:44 -0400 |
---|---|---|
committer | Jiri Kosina <jkosina@suse.cz> | 2010-04-22 20:08:44 -0400 |
commit | 6c9468e9eb1252eaefd94ce7f06e1be9b0b641b1 (patch) | |
tree | 797676a336b050bfa1ef879377c07e541b9075d6 /Documentation/networking | |
parent | 4cb3ca7cd7e2cae8d1daf5345ec99a1e8502cf3f (diff) | |
parent | c81eddb0e3728661d1585fbc564449c94165cc36 (diff) |
Merge branch 'master' into for-next
Diffstat (limited to 'Documentation/networking')
-rw-r--r-- | Documentation/networking/Makefile | 2 | ||||
-rw-r--r-- | Documentation/networking/stmmac.txt | 143 | ||||
-rw-r--r-- | Documentation/networking/timestamping.txt | 76 | ||||
-rw-r--r-- | Documentation/networking/timestamping/Makefile | 11 | ||||
-rw-r--r-- | Documentation/networking/timestamping/timestamping.c | 10 |
5 files changed, 205 insertions, 37 deletions
diff --git a/Documentation/networking/Makefile b/Documentation/networking/Makefile index 6d8af1ac56c4..5aba7a33aeeb 100644 --- a/Documentation/networking/Makefile +++ b/Documentation/networking/Makefile | |||
@@ -6,3 +6,5 @@ hostprogs-y := ifenslave | |||
6 | 6 | ||
7 | # Tell kbuild to always build the programs | 7 | # Tell kbuild to always build the programs |
8 | always := $(hostprogs-y) | 8 | always := $(hostprogs-y) |
9 | |||
10 | obj-m := timestamping/ | ||
diff --git a/Documentation/networking/stmmac.txt b/Documentation/networking/stmmac.txt new file mode 100644 index 000000000000..7ee770b5ef5f --- /dev/null +++ b/Documentation/networking/stmmac.txt | |||
@@ -0,0 +1,143 @@ | |||
1 | STMicroelectronics 10/100/1000 Synopsys Ethernet driver | ||
2 | |||
3 | Copyright (C) 2007-2010 STMicroelectronics Ltd | ||
4 | Author: Giuseppe Cavallaro <peppe.cavallaro@st.com> | ||
5 | |||
6 | This is the driver for the MAC 10/100/1000 on-chip Ethernet controllers | ||
7 | (Synopsys IP blocks); it has been fully tested on STLinux platforms. | ||
8 | |||
9 | Currently this network device driver is for all STM embedded MAC/GMAC | ||
10 | (7xxx SoCs). | ||
11 | |||
12 | DWC Ether MAC 10/100/1000 Universal version 3.41a and DWC Ether MAC 10/100 | ||
13 | Universal version 4.0 have been used for developing the first code | ||
14 | implementation. | ||
15 | |||
16 | Please, for more information also visit: www.stlinux.com | ||
17 | |||
18 | 1) Kernel Configuration | ||
19 | The kernel configuration option is STMMAC_ETH: | ||
20 | Device Drivers ---> Network device support ---> Ethernet (1000 Mbit) ---> | ||
21 | STMicroelectronics 10/100/1000 Ethernet driver (STMMAC_ETH) | ||
22 | |||
23 | 2) Driver parameters list: | ||
24 | debug: message level (0: no output, 16: all); | ||
25 | phyaddr: to manually provide the physical address to the PHY device; | ||
26 | dma_rxsize: DMA rx ring size; | ||
27 | dma_txsize: DMA tx ring size; | ||
28 | buf_sz: DMA buffer size; | ||
29 | tc: control the HW FIFO threshold; | ||
30 | tx_coe: Enable/Disable Tx Checksum Offload engine; | ||
31 | watchdog: transmit timeout (in milliseconds); | ||
32 | flow_ctrl: Flow control ability [on/off]; | ||
33 | pause: Flow Control Pause Time; | ||
34 | tmrate: timer period (only if timer optimisation is configured). | ||
35 | |||
36 | 3) Command line options | ||
37 | Driver parameters can be also passed in command line by using: | ||
38 | stmmaceth=dma_rxsize:128,dma_txsize:512 | ||
39 | |||
40 | 4) Driver information and notes | ||
41 | |||
42 | 4.1) Transmit process | ||
43 | The xmit method is invoked when the kernel needs to transmit a packet; it sets | ||
44 | the descriptors in the ring and informs the DMA engine that there is a packet | ||
45 | ready to be transmitted. | ||
46 | Once the controller has finished transmitting the packet, an interrupt is | ||
47 | triggered; So the driver will be able to release the socket buffers. | ||
48 | By default, the driver sets the NETIF_F_SG bit in the features field of the | ||
49 | net_device structure enabling the scatter/gather feature. | ||
50 | |||
51 | 4.2) Receive process | ||
52 | When one or more packets are received, an interrupt happens. The interrupts | ||
53 | are not queued so the driver has to scan all the descriptors in the ring during | ||
54 | the receive process. | ||
55 | This is based on NAPI so the interrupt handler signals only if there is work to be | ||
56 | done, and it exits. | ||
57 | Then the poll method will be scheduled at some future point. | ||
58 | The incoming packets are stored, by the DMA, in a list of pre-allocated socket | ||
59 | buffers in order to avoid the memcpy (Zero-copy). | ||
60 | |||
61 | 4.3) Timer-Driver Interrupt | ||
62 | Instead of having the device that asynchronously notifies the frame receptions, the | ||
63 | driver configures a timer to generate an interrupt at regular intervals. | ||
64 | Based on the granularity of the timer, the frames that are received by the device | ||
65 | will experience different levels of latency. Some NICs have dedicated timer | ||
66 | device to perform this task. STMMAC can use either the RTC device or the TMU | ||
67 | channel 2 on STLinux platforms. | ||
68 | The timers frequency can be passed to the driver as parameter; when change it, | ||
69 | take care of both hardware capability and network stability/performance impact. | ||
70 | Several performance tests on STM platforms showed this optimisation allows to spare | ||
71 | the CPU while having the maximum throughput. | ||
72 | |||
73 | 4.4) WOL | ||
74 | Wake up on Lan feature through Magic Frame is only supported for the GMAC | ||
75 | core. | ||
76 | |||
77 | 4.5) DMA descriptors | ||
78 | Driver handles both normal and enhanced descriptors. The latter has been only | ||
79 | tested on DWC Ether MAC 10/100/1000 Universal version 3.41a. | ||
80 | |||
81 | 4.6) Ethtool support | ||
82 | Ethtool is supported. Driver statistics and internal errors can be taken using: | ||
83 | ethtool -S ethX command. It is possible to dump registers etc. | ||
84 | |||
85 | 4.7) Jumbo and Segmentation Offloading | ||
86 | Jumbo frames are supported and tested for the GMAC. | ||
87 | The GSO has been also added but it's performed in software. | ||
88 | LRO is not supported. | ||
89 | |||
90 | 4.8) Physical | ||
91 | The driver is compatible with PAL to work with PHY and GPHY devices. | ||
92 | |||
93 | 4.9) Platform information | ||
94 | Several information came from the platform; please refer to the | ||
95 | driver's Header file in include/linux directory. | ||
96 | |||
97 | struct plat_stmmacenet_data { | ||
98 | int bus_id; | ||
99 | int pbl; | ||
100 | int has_gmac; | ||
101 | void (*fix_mac_speed)(void *priv, unsigned int speed); | ||
102 | void (*bus_setup)(unsigned long ioaddr); | ||
103 | #ifdef CONFIG_STM_DRIVERS | ||
104 | struct stm_pad_config *pad_config; | ||
105 | #endif | ||
106 | void *bsp_priv; | ||
107 | }; | ||
108 | |||
109 | Where: | ||
110 | - pbl (Programmable Burst Length) is maximum number of | ||
111 | beats to be transferred in one DMA transaction. | ||
112 | GMAC also enables the 4xPBL by default. | ||
113 | - fix_mac_speed and bus_setup are used to configure internal target | ||
114 | registers (on STM platforms); | ||
115 | - has_gmac: GMAC core is on board (get it at run-time in the next step); | ||
116 | - bus_id: bus identifier. | ||
117 | |||
118 | struct plat_stmmacphy_data { | ||
119 | int bus_id; | ||
120 | int phy_addr; | ||
121 | unsigned int phy_mask; | ||
122 | int interface; | ||
123 | int (*phy_reset)(void *priv); | ||
124 | void *priv; | ||
125 | }; | ||
126 | |||
127 | Where: | ||
128 | - bus_id: bus identifier; | ||
129 | - phy_addr: physical address used for the attached phy device; | ||
130 | set it to -1 to get it at run-time; | ||
131 | - interface: physical MII interface mode; | ||
132 | - phy_reset: hook to reset HW function. | ||
133 | |||
134 | TODO: | ||
135 | - Continue to make the driver more generic and suitable for other Synopsys | ||
136 | Ethernet controllers used on other architectures (i.e. ARM). | ||
137 | - 10G controllers are not supported. | ||
138 | - MAC uses Normal descriptors and GMAC uses enhanced ones. | ||
139 | This is a limit that should be reviewed. MAC could want to | ||
140 | use the enhanced structure. | ||
141 | - Checksumming: Rx/Tx csum is done in HW in case of GMAC only. | ||
142 | - Review the timer optimisation code to use an embedded device that seems to be | ||
143 | available in new chip generations. | ||
diff --git a/Documentation/networking/timestamping.txt b/Documentation/networking/timestamping.txt index 0e58b4539176..e8c8f4f06c67 100644 --- a/Documentation/networking/timestamping.txt +++ b/Documentation/networking/timestamping.txt | |||
@@ -41,11 +41,12 @@ SOF_TIMESTAMPING_SOFTWARE: return system time stamp generated in | |||
41 | SOF_TIMESTAMPING_TX/RX determine how time stamps are generated. | 41 | SOF_TIMESTAMPING_TX/RX determine how time stamps are generated. |
42 | SOF_TIMESTAMPING_RAW/SYS determine how they are reported in the | 42 | SOF_TIMESTAMPING_RAW/SYS determine how they are reported in the |
43 | following control message: | 43 | following control message: |
44 | struct scm_timestamping { | 44 | |
45 | struct timespec systime; | 45 | struct scm_timestamping { |
46 | struct timespec hwtimetrans; | 46 | struct timespec systime; |
47 | struct timespec hwtimeraw; | 47 | struct timespec hwtimetrans; |
48 | }; | 48 | struct timespec hwtimeraw; |
49 | }; | ||
49 | 50 | ||
50 | recvmsg() can be used to get this control message for regular incoming | 51 | recvmsg() can be used to get this control message for regular incoming |
51 | packets. For send time stamps the outgoing packet is looped back to | 52 | packets. For send time stamps the outgoing packet is looped back to |
@@ -87,12 +88,13 @@ by the network device and will be empty without that support. | |||
87 | SIOCSHWTSTAMP: | 88 | SIOCSHWTSTAMP: |
88 | 89 | ||
89 | Hardware time stamping must also be initialized for each device driver | 90 | Hardware time stamping must also be initialized for each device driver |
90 | that is expected to do hardware time stamping. The parameter is: | 91 | that is expected to do hardware time stamping. The parameter is defined in |
92 | /include/linux/net_tstamp.h as: | ||
91 | 93 | ||
92 | struct hwtstamp_config { | 94 | struct hwtstamp_config { |
93 | int flags; /* no flags defined right now, must be zero */ | 95 | int flags; /* no flags defined right now, must be zero */ |
94 | int tx_type; /* HWTSTAMP_TX_* */ | 96 | int tx_type; /* HWTSTAMP_TX_* */ |
95 | int rx_filter; /* HWTSTAMP_FILTER_* */ | 97 | int rx_filter; /* HWTSTAMP_FILTER_* */ |
96 | }; | 98 | }; |
97 | 99 | ||
98 | Desired behavior is passed into the kernel and to a specific device by | 100 | Desired behavior is passed into the kernel and to a specific device by |
@@ -139,42 +141,56 @@ enum { | |||
139 | /* time stamp any incoming packet */ | 141 | /* time stamp any incoming packet */ |
140 | HWTSTAMP_FILTER_ALL, | 142 | HWTSTAMP_FILTER_ALL, |
141 | 143 | ||
142 | /* return value: time stamp all packets requested plus some others */ | 144 | /* return value: time stamp all packets requested plus some others */ |
143 | HWTSTAMP_FILTER_SOME, | 145 | HWTSTAMP_FILTER_SOME, |
144 | 146 | ||
145 | /* PTP v1, UDP, any kind of event packet */ | 147 | /* PTP v1, UDP, any kind of event packet */ |
146 | HWTSTAMP_FILTER_PTP_V1_L4_EVENT, | 148 | HWTSTAMP_FILTER_PTP_V1_L4_EVENT, |
147 | 149 | ||
148 | ... | 150 | /* for the complete list of values, please check |
151 | * the include file /include/linux/net_tstamp.h | ||
152 | */ | ||
149 | }; | 153 | }; |
150 | 154 | ||
151 | 155 | ||
152 | DEVICE IMPLEMENTATION | 156 | DEVICE IMPLEMENTATION |
153 | 157 | ||
154 | A driver which supports hardware time stamping must support the | 158 | A driver which supports hardware time stamping must support the |
155 | SIOCSHWTSTAMP ioctl. Time stamps for received packets must be stored | 159 | SIOCSHWTSTAMP ioctl and update the supplied struct hwtstamp_config with |
156 | in the skb with skb_hwtstamp_set(). | 160 | the actual values as described in the section on SIOCSHWTSTAMP. |
161 | |||
162 | Time stamps for received packets must be stored in the skb. To get a pointer | ||
163 | to the shared time stamp structure of the skb call skb_hwtstamps(). Then | ||
164 | set the time stamps in the structure: | ||
165 | |||
166 | struct skb_shared_hwtstamps { | ||
167 | /* hardware time stamp transformed into duration | ||
168 | * since arbitrary point in time | ||
169 | */ | ||
170 | ktime_t hwtstamp; | ||
171 | ktime_t syststamp; /* hwtstamp transformed to system time base */ | ||
172 | }; | ||
157 | 173 | ||
158 | Time stamps for outgoing packets are to be generated as follows: | 174 | Time stamps for outgoing packets are to be generated as follows: |
159 | - In hard_start_xmit(), check if skb_hwtstamp_check_tx_hardware() | 175 | - In hard_start_xmit(), check if skb_tx(skb)->hardware is set no-zero. |
160 | returns non-zero. If yes, then the driver is expected | 176 | If yes, then the driver is expected to do hardware time stamping. |
161 | to do hardware time stamping. | ||
162 | - If this is possible for the skb and requested, then declare | 177 | - If this is possible for the skb and requested, then declare |
163 | that the driver is doing the time stamping by calling | 178 | that the driver is doing the time stamping by setting the field |
164 | skb_hwtstamp_tx_in_progress(). A driver not supporting | 179 | skb_tx(skb)->in_progress non-zero. You might want to keep a pointer |
165 | hardware time stamping doesn't do that. A driver must never | 180 | to the associated skb for the next step and not free the skb. A driver |
166 | touch sk_buff::tstamp! It is used to store how time stamping | 181 | not supporting hardware time stamping doesn't do that. A driver must |
167 | for an outgoing packets is to be done. | 182 | never touch sk_buff::tstamp! It is used to store software generated |
183 | time stamps by the network subsystem. | ||
168 | - As soon as the driver has sent the packet and/or obtained a | 184 | - As soon as the driver has sent the packet and/or obtained a |
169 | hardware time stamp for it, it passes the time stamp back by | 185 | hardware time stamp for it, it passes the time stamp back by |
170 | calling skb_hwtstamp_tx() with the original skb, the raw | 186 | calling skb_hwtstamp_tx() with the original skb, the raw |
171 | hardware time stamp and a handle to the device (necessary | 187 | hardware time stamp. skb_hwtstamp_tx() clones the original skb and |
172 | to convert the hardware time stamp to system time). If obtaining | 188 | adds the timestamps, therefore the original skb has to be freed now. |
173 | the hardware time stamp somehow fails, then the driver should | 189 | If obtaining the hardware time stamp somehow fails, then the driver |
174 | not fall back to software time stamping. The rationale is that | 190 | should not fall back to software time stamping. The rationale is that |
175 | this would occur at a later time in the processing pipeline | 191 | this would occur at a later time in the processing pipeline than other |
176 | than other software time stamping and therefore could lead | 192 | software time stamping and therefore could lead to unexpected deltas |
177 | to unexpected deltas between time stamps. | 193 | between time stamps. |
178 | - If the driver did not call skb_hwtstamp_tx_in_progress(), then | 194 | - If the driver did not call set skb_tx(skb)->in_progress, then |
179 | dev_hard_start_xmit() checks whether software time stamping | 195 | dev_hard_start_xmit() checks whether software time stamping |
180 | is wanted as fallback and potentially generates the time stamp. | 196 | is wanted as fallback and potentially generates the time stamp. |
diff --git a/Documentation/networking/timestamping/Makefile b/Documentation/networking/timestamping/Makefile index 2a1489fdc036..e79973443e9f 100644 --- a/Documentation/networking/timestamping/Makefile +++ b/Documentation/networking/timestamping/Makefile | |||
@@ -1,6 +1,13 @@ | |||
1 | CPPFLAGS = -I../../../include | 1 | # kbuild trick to avoid linker error. Can be omitted if a module is built. |
2 | obj- := dummy.o | ||
2 | 3 | ||
3 | timestamping: timestamping.c | 4 | # List of programs to build |
5 | hostprogs-y := timestamping | ||
6 | |||
7 | # Tell kbuild to always build the programs | ||
8 | always := $(hostprogs-y) | ||
9 | |||
10 | HOSTCFLAGS_timestamping.o += -I$(objtree)/usr/include | ||
4 | 11 | ||
5 | clean: | 12 | clean: |
6 | rm -f timestamping | 13 | rm -f timestamping |
diff --git a/Documentation/networking/timestamping/timestamping.c b/Documentation/networking/timestamping/timestamping.c index bab619a48214..8ba82bfe6a33 100644 --- a/Documentation/networking/timestamping/timestamping.c +++ b/Documentation/networking/timestamping/timestamping.c | |||
@@ -41,9 +41,9 @@ | |||
41 | #include <arpa/inet.h> | 41 | #include <arpa/inet.h> |
42 | #include <net/if.h> | 42 | #include <net/if.h> |
43 | 43 | ||
44 | #include "asm/types.h" | 44 | #include <asm/types.h> |
45 | #include "linux/net_tstamp.h" | 45 | #include <linux/net_tstamp.h> |
46 | #include "linux/errqueue.h" | 46 | #include <linux/errqueue.h> |
47 | 47 | ||
48 | #ifndef SO_TIMESTAMPING | 48 | #ifndef SO_TIMESTAMPING |
49 | # define SO_TIMESTAMPING 37 | 49 | # define SO_TIMESTAMPING 37 |
@@ -164,7 +164,7 @@ static void printpacket(struct msghdr *msg, int res, | |||
164 | 164 | ||
165 | gettimeofday(&now, 0); | 165 | gettimeofday(&now, 0); |
166 | 166 | ||
167 | printf("%ld.%06ld: received %s data, %d bytes from %s, %d bytes control messages\n", | 167 | printf("%ld.%06ld: received %s data, %d bytes from %s, %zu bytes control messages\n", |
168 | (long)now.tv_sec, (long)now.tv_usec, | 168 | (long)now.tv_sec, (long)now.tv_usec, |
169 | (recvmsg_flags & MSG_ERRQUEUE) ? "error" : "regular", | 169 | (recvmsg_flags & MSG_ERRQUEUE) ? "error" : "regular", |
170 | res, | 170 | res, |
@@ -173,7 +173,7 @@ static void printpacket(struct msghdr *msg, int res, | |||
173 | for (cmsg = CMSG_FIRSTHDR(msg); | 173 | for (cmsg = CMSG_FIRSTHDR(msg); |
174 | cmsg; | 174 | cmsg; |
175 | cmsg = CMSG_NXTHDR(msg, cmsg)) { | 175 | cmsg = CMSG_NXTHDR(msg, cmsg)) { |
176 | printf(" cmsg len %d: ", cmsg->cmsg_len); | 176 | printf(" cmsg len %zu: ", cmsg->cmsg_len); |
177 | switch (cmsg->cmsg_level) { | 177 | switch (cmsg->cmsg_level) { |
178 | case SOL_SOCKET: | 178 | case SOL_SOCKET: |
179 | printf("SOL_SOCKET "); | 179 | printf("SOL_SOCKET "); |