TC(9)

📦 version 11.0, in nixpkgs unstable

💖 TC(9) — TURBOchannel bus: Kernel Developer's Manual edition 💖

🎀 NAME 🎀

okay so this page is the whole TURBOchannel bus situation, and the squad in the group chat is:

  • TC
  • tc_intr_establish
  • tc_intr_disestablish
  • tc_intr_evcnt
  • tc_mb
  • tc_wmb
  • tc_syncbus
  • tc_badaddr
  • TC_DENSE_TO_SPARSE
  • TC_PHYS_TO_UNCACHED

— all of these are the TURBOchannel bus, periodt. 💅

✨ SYNOPSIS ✨

copy these includes and prototypes exactly, bestie, no cap:

#include <sys/bus.h>
#include <dev/tc/tcvar.h>
#include <dev/tc/tcdevs.h>

void
tc_intr_establish(struct device *dev, void *cookie, int level,
    int (*handler)(void *), void *arg);

void
tc_intr_disestablish(struct device *dev, void *cookie);

const struct evcnt *
tc_intr_evcnt(struct device *dev, void *cookie);

void
tc_mb();

void
tc_wmb();

void
tc_syncbus();

int
tc_badaddr(tc_addr_t tcaddr);

tc_addr_t
TC_DENSE_TO_SPARSE(tc_addr_t addr);

tc_addr_t
TC_PHYS_TO_UNCACHED(tc_addr_t addr);

🦋 DESCRIPTION 🦋

The TC device provides support for the DEC TURBOchannel bus found on all DEC TURBOchannel machines with MIPS (DECstation 5000 series, excluding the 5000/200) and Alpha (3000-series) systems. TURBOchannel is a 32-bit wide synchronous DMA-capable bus, running at 25 MHz on higher-end machines and at 12.5 MHz on lower-end machines.

🌸 DATA TYPES 🌸

Drivers for devices attached to the TURBOchannel bus will make use of the following data types:

struct tc_attach_args — a structure used to inform the driver of TURBOchannel bus properties. It contains the following members:

bus_space_tag_t ta_memt;
bus_dma_tag_t   ta_dmat;
char            ta_modname[TC_ROM_LLEN+1];
u_int           ta_slot;
tc_offset_t     ta_offset;
tc_addr_t       ta_addr;
void            *ta_cookie;
u_int           ta_busspeed;

The ta_busspeed member specifies the TURBOchannel bus speed and is useful for time-related functions. The values are TC_SPEED_12_5_MHZ for the 12.5 MHz bus and TC_SPEED_25_MHZ for the 50 MHz bus.

bestie, yes: the page pairs TC_SPEED_25_MHZ with the 50 MHz bus. That's the lore we were given, and we report it with love. 💀

💅 FUNCTIONS 💅

  • tc_intr_establish(dev, cookie, level, handler, arg) — establish an interrupt handler with device dev for the interrupt described completely by cookie, the value passed to the driver in the ta_cookie member of the tc_attach_args structure. The priority of the interrupt is specified by level. When the interrupt occurs the function handler is called with argument arg.
  • tc_intr_disestablish(dev, cookie) — dis-establish the interrupt handler with device dev for the interrupt described completely by cookie.
  • tc_intr_evcnt(dev, cookie) — do interrupt event counting with device dev for the event described completely by cookie; the synopsis gives its return type as const struct evcnt *.
  • tc_mb() — a read/write memory barrier. Any CPU-to-memory reads/writes before the barrier must complete before any CPU-to-memory reads/writes after it.
  • tc_wmb() — a write memory barrier. Any CPU-to-memory writes before the barrier must complete before any CPU-to-memory writes after it.
  • tc_syncbus() — synchronise writes on the TURBOchannel bus by ensuring CPU writes are propagated across the TURBOchannel bus.
  • tc_badaddr(tcaddr) — returns non-zero if the given address tcaddr is invalid.
  • TC_DENSE_TO_SPARSE(addr) — convert the given physical address addr in TURBOchannel dense space to the corresponding address in TURBOchannel sparse space.
  • TC_PHYS_TO_UNCACHED(addr) — convert the given system memory physical address addr to the physical address of the corresponding region that is not cached.

🌈 AUTOCONFIGURATION 🌈

The TURBOchannel bus is a direct-connection bus. During autoconfiguration, the parent specifies the name of the found TURBOchannel module into the ta_modname member of the tc_attach_args structure. Drivers should match on this name.

⭐ DMA SUPPORT ⭐

The TURBOchannel bus supports 32-bit, bidirectional DMA transfers. Support is provided by the standard bus_dma(9) interface.

🍓 CODE REFERENCES 🍓

The TURBOchannel subsystem itself is implemented within the file sys/dev/tc/tc_subr.c. Machine-dependent portions can be found in sys/arch/<arch>/tc/tcbus.c.

👑 SEE ALSO 👑

go read these too, bestie:

💌 xoxo, bestie — this page is from Debian, dated October 7, 2001. Periodt. 🫶

📦 where this page comes from