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- Normally, the driver allocates an mbuf cluster for each receive descriptor. This is because we have to be prepared to accomodate up to 1500 bytes (a cluster buffer can hold up to 2K). However, using up a whole cluster buffer for a tiny packet is a bit of a waste. Also, it seems to me that sometimes mbufs will linger in the kernel for a while after being passed out of the driver, which means we might drain the mbuf cluster pool. The cluster pool is smaller than the mbuf pool in general, so we do the following: if the packet is less that MINCLSIZE bytes, then we copy it into a small mbuf chain and leave the mbuf cluster in place for another go-round. This saves mbuf clusters in some cases while still allowing them to be used for heavy traffic exchanges with lots of full-sized frames. - The transmit descriptor has a bit in the control word which allows the driver to request that a 'TX OK' interrupt be generated when a frame has been completed. Sometimes, a frame can be fragmented across several descriptors. The manual for the real DEC 21140A says that if this happens, the 'TX interrupt request' bit is only valid in the descriptor of the last fragment. With the ASIX chip, it seems the 'TX interrupt request' bit is only valid in the descriptor of the _first_ fragment. Actually, the manual contains conflicting information, but I think it's supposed to be the first fragment. To play it safe, set the bit in both the first and last fragment to be sure that we get a TX OK interrupt. Without this fix, the driver can sometimes be late in releasing mbufs from the transmit queue after transmission. |
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.. | ||
adv_pci.c | ||
adw_pci.c | ||
ahc_pci.c | ||
brktree_reg.h | ||
brooktree848.c | ||
bt848_i2c.c | ||
bt848_i2c.h | ||
bt_pci.c | ||
cy_pci.c | ||
cy_pcireg.h | ||
dc21040reg.h | ||
dpt_pci.c | ||
dpt_pci.h | ||
es1370.c | ||
es1370_reg.h | ||
ide_pci.c | ||
ide_pcireg.h | ||
if_ax.c | ||
if_axreg.h | ||
if_de.c | ||
if_devar.h | ||
if_ed_p.c | ||
if_en_pci.c | ||
if_fpa.c | ||
if_fxp.c | ||
if_fxpreg.h | ||
if_fxpvar.h | ||
if_lnc_p.c | ||
if_mx.c | ||
if_mxreg.h | ||
if_pn.c | ||
if_pnreg.h | ||
if_rl.c | ||
if_rlreg.h | ||
if_sr_p.c | ||
if_tl.c | ||
if_tlreg.h | ||
if_tx.c | ||
if_txvar.h | ||
if_vr.c | ||
if_vrreg.h | ||
if_vx_pci.c | ||
if_wb.c | ||
if_wbreg.h | ||
if_xl.c | ||
if_xlreg.h | ||
isp_pci.c | ||
locate.pl | ||
meteor.c | ||
meteor_reg.h | ||
ncr.c | ||
ncrreg.h | ||
pci.c | ||
pci_compat.c | ||
pci_ioctl.h | ||
pcic_p.c | ||
pcic_p.h | ||
pcireg.h | ||
pcisupport.c | ||
pcivar.h | ||
README.bt848 | ||
scsiiom.c | ||
simos.c | ||
simos.h | ||
wdc_p.c | ||
xrpu.c |
------------------------------------------------------------------------------- Recent versions of 3.0-current have the bktr driver built in. Older versions of 3.0 and all versions of 2.2 need to have the driver files installed by hand: cp ioctl_bt848.h /sys/i386/include/ cp brktree_reg.h brooktree848.c /sys/pci/ In /sys/conf/files add: pci/brooktree848.c optional bktr device-driver ------------------------------------------------------------------------------- In all cases you will need to add the driver to your kernel: In your kernel configuration file: controller pci0 #if you already have this line don't add it. device bktr0 There is no need to specify DMA channels nor interrupts for this driver. ------------------------------------------------------------------------------- Finally you need to create nodes for the driver: Create a video device: mknod /dev/bktr0 c 92 0 Create a tuner device: mknod /dev/tuner0 c 92 16 ------------------------------------------------------------------------------- The code attempts to auto-probe code to detect card/tuner types. The detected card is printed in the dmesg as the driver is loaded. If this fails to detect the proper card you can override it in brooktree848.c: #define OVERRIDE_CARD <card type> where <card type> is one of: CARD_UNKNOWN CARD_MIRO CARD_HAUPPAUGE CARD_STB CARD_INTEL ------------------------------------------------------------------------------- This model now separates the "tuner control" items into a minor device: minor device layout: xxxxxxxx xxxT UUUU UUUU: the card (ie UNIT) identifier, 0 thru 15 T == 0: video device T == 1: tuner device Access your tuner ioctl thru your tuner device handle and anything which controls the video capture process thru the video device handle. Certain ioctl()s such as video source are available thru both devices. ------------------------------------------------------------------------------- If your tuner does not work properly or is not recognized properly try setting the tuner type via or card type: sysctl -w hw.bt848.card=<integer> current valid values are 0 to 5 inclusive sysctl -w hw.bt848.tuner=<integer> where integer is a value from 1 to 10 systcl -w hw.bt848.reverse_mute=<1 | 0> to reverse the mute function in the driver set variable to 1. The exact format of the sysctl bt848 variable is: unit << 8 | value unit identifies the pci bt848 board to be affected 0 is the first bt848 board, 1 is the second bt848 board. value denotes the integer value for tuners is a value from 0 to 10 for reversing the mute function of the tuner the value is 1 or 0. to find out all the bt848 variables: sysctl hw.bt848 ------------------------------------------------------------------------------- The bt848 driver consists of: src/sys/i386/include/ioctl_bt848.h src/sys/pci/brktree_reg.h src/sys/pci/brooktree848.c