CARDBUS(9)

📦 version 11.0, in nixpkgs unstable

okay bestie, welcome to CARDBUS(9) from the Kernel Developer's Manual — the support page for CardBus PC-Card devices. grab a strawberry 🍓 and let's get into it.

🌸 NAME 🌸

Cardbus, cardbus_attach_card, cardbus_detach_card, cardbus_function_enable, cardbus_function_disable, cardbus_mapreg_map, cardbus_mapreg_unmap, cardbus_get_capability, cardbus_make_tag, cardbus_conf_read, cardbus_conf_write, cardbus_intr_establish, cardbus_intr_disestablish, CARDBUS_VENDOR, CARDBUS_PRODUCT, Cardbus_function_enable, Cardbus_function_disable, Cardbus_mapreg_map, Cardbus_mapreg_unmap, Cardbus_make_tag, Cardbus_conf_read, Cardbus_conf_write — support for CardBus PC-Card devices 💅

✨ SYNOPSIS ✨

#include <sys/bus.h>
#include <dev/cardbus/cardbusvar.h>
#include <dev/cardbus/cardbusreg.h>
#include <dev/cardbus/cardbusdevs.h>

int
cardbus_attach_card(struct cardbus_softc *csc);

void
cardbus_detach_card(struct cardbus_softc *csc);

int
cardbus_function_enable(struct cardbus_softc *csc, int function);

int
cardbus_function_disable(struct cardbus_softc *csc, int function);

int
cardbus_mapreg_map(struct cardbus_softc *csc, int cf, int reg,
    pcireg_t type, int busflags, bus_space_tag_t *tagp,
    bus_space_handle_t *handlep, bus_addr_t *basep, bus_size_t *sizep);

int
cardbus_mapreg_unmap(struct cardbus_softc *csc, int cf, int reg,
    bus_space_tag_t tag, bus_space_handle_t handle, bus_size_t size);

int
cardbus_get_capability(cardbus_chipset_tag_t cc,
    cardbus_function_tag_t cf, pcitag_t tag, int capid, int *offsetp,
    pcireg_t *valuep);

pcitag_t
cardbus_make_tag(cardbus_chipset_tag_t cc, int cf, int bus, int device,
    int function);

pcireg_t
cardbus_conf_read(cardbus_chipset_tag_t cc, int cf, pcitag_t tag,
    int offs);

void
cardbus_conf_write(cardbus_chipset_tag_t cc, int cf, pcitag_t tag,
    int offs, busreg_t val);

void *
cardbus_intr_establish(cardbus_chipset_tag_t cc,
    cardbus_function_tag_t cf, cardbus_intr_handle_t irq, int level,
    int (*handler)(void *), void *arg);

void
cardbus_intr_disestablish(cardbus_chipset_tag_t cc,
    cardbus_function_tag_t cf, void *ih);

int
CARDBUS_VENDOR(pcireg_t id);

int
CARDBUS_PRODUCT(pcireg_t id);

int
Cardbus_function_enable(cardbus_devfunc_t ct);

int
Cardbus_function_disable(cardbus_devfunc_t ct);

int
Cardbus_mapreg_map(cardbus_devfunc_t ct, int reg, pcireg_t type,
    int busflags, bus_space_tag_t *tagp, bus_space_handle_t *handlep,
    bus_addr_t *basep, bus_size_t *sizep);

int
Cardbus_mapreg_unmap(cardbus_devfunc_t ct, int reg, bus_space_tag_t tag,
    bus_space_handle_t handle, bus_size_t size);

pcitag_t
Cardbus_make_tag(cardbus_devfunc_t ct);

pcireg_t
Cardbus_conf_read(cardbus_devfunc_t ct, pcitag_t tag, int offs);

void
Cardbus_conf_write(cardbus_devfunc_t ct, pcitag_t tag, int offs,
    busreg_t val);

🌈 DESCRIPTION 🌈

The machine-independent Cardbus subsystem provides support for CardBus devices. it's giving "glow-up era" for the PC-Card world 💖

The CardBus interface is an improvement to the PC-Card interface supported by pcmcia(9). It introduces several new capabilities such as 32-bit addressing, 33MHz operation, busmaster operation and 3.3 volt low-voltage power. It remains compatible with all features of the PC-Card standard. iconic behaviour, no cap.

The CardBus interface signaling protocol is derived from the PCI signaling protocol. There are some differences between PCI and CardBus, however operations are identical for most functions implemented. Since a 32-bit CardBus interface is also defined for 16-bit PC-Cards, the same Card Services client gets used to manage both CardBus and PCMCIA PC-Cards. By interrogating the card upon detection of an insertion event, NetBSD determines whether the card requires Cardbus support or not, and then applies the appropriate power and signaling protocol requirements. main character energy fr fr 🦋

🎀 DATA TYPES 🎀

Drivers attached to the CardBus will make use of the following data types:

struct cardbus_attach_args

Devices have their identity recorded in this structure. It contains the following members:

cardbus_devfunc_t ca_ct;
bus_space_tag_t ca_iot;       /* CardBus I/O space tag */
bus_space_tag_t ca_memt;      /* CardBus MEM space tag */
bus_dma_tag_t ca_dmat;        /* DMA tag */
u_int ca_device;
pcitag_t ca_tag;
pcireg_t ca_id;
pcireg_t ca_class;
cardbus_intr_line_t ca_intrline; /* interrupt info */
struct cardbus_cis_info ca_cis;

💅 FUNCTIONS 💅

cardbus_attach_card(csc)

Attaches the card on the slot by turning on the power, reading and analysing the tuple, and setting the configuration index. This function returns the number of recognised device functions. If no device functions are recognised it returns zero. lowkey doing the whole vibe check on the card ✨

cardbus_detach_card(csc)

Detaches the card on the slot by releasing resources and turning off the power.

bestie, this function must not be called under interrupt context. that is not a drill 😭

cardbus_function_enable(csc, function)

Enables device function function on the card. Power will be applied if it hasn't already. slay, let there be power ⚡

cardbus_function_disable(csc, function)

Disables device function function on the card. When no device functions are enabled, the turn is turned off. yes, that is literally what the page says 🫠

cardbus_mapreg_map(csc, cf, reg, type, busflags, tagp, handlep, basep, sizep)

Maps bus-space on the value of Base Address Register (BAR) indexed by reg for device function cf. The bus-space configuration is returned in tagp, handlep, basep, and sizep. it's giving "mapped and thriving" 💖

cardbus_mapreg_unmap(csc, cf, reg, tag, handle, bus_size_t size)

Releases bus-space region for device function cf specified by tag, handle and size. reg is the offset of the BAR register. clean up your room, bestie 🧹

cardbus_get_capability(cc, cf, tag, capid, offsetp, valuep)

Finds the PCI capability for the device function cf specified by capid. Returns the capability in offsetp and valuep. capability unlocked 🔥

cardbus_make_tag(cc, cf, bus, device, function)

Makes a tag to access config space of a CardBus card. It works the same as pci_make_tag(). tag, you're it 🎀

cardbus_conf_read(cc, cf, tag, offs)

Reads the config space of a CardBus card. It works the same as pci_conf_read(). reading the config like it's the group chat 👀

cardbus_conf_write(cc, cf, tag, offs, val)

Writes to the config space of a CardBus card. It works same as pci_conf_write(). writing it down so we don't forget ✍️

cardbus_intr_establish(cc, cf, irq, level, handler, arg)

Establishes an interrupt handler for device function cf. The priority of the interrupt is specified by level. When the interrupt occurs the function handler is called with argument arg. The return value is a handle for the interrupt handler. cardbus_intr_establish() returns an opaque handle to an event descriptor if it succeeds, and returns NULL on failure. interrupt era, established and iconic 💥

cardbus_intr_disestablish(cc, cf, ih)

Dis-establishes the interrupt handler for device function cf with handle ih. The handle was returned from cardbus_intr_establish(). okay bye interrupt, we hardly knew ye 👋

CARDBUS_VENDOR(id)

Returns the CardBus vendor ID for device id. vendor reveal 🕵️‍♀️

CARDBUS_PRODUCT(id)

Returns the CardBus product ID for device id. product reveal 🏷️

The Cardbus_*() functions are convenience functions taking a cardbus_devfunc_t argument and perform the same operation as their namesake described above. they're the "same energy, shorter signature" besties 🫶

🦋 AUTOCONFIGURATION 🦋

During autoconfiguration, a Cardbus driver will receive a pointer to struct cardbus_attach_args describing the device attaches to the CardBus. Drivers match the device using the ca_id member using CARDBUS_VENDOR() and CARDBUS_PRODUCT(). matching energy, but make it kernel 👑

During the driver attach step, drivers should initially map the device I/O and memory resources using cardbus_mapreg_map() or Cardbus_mapreg_map(). Upon successful allocation of resources, power can be applied to the device with cardbus_function_enable() or Cardbus_function_enable(), so that device-specific interrogation can be performed. Finally, power should be removed from the device using cardbus_function_disable() or Cardbus_function_disable(). full attach-to-detach storyline, we love a character arc 😭

Since CardBus devices support dynamic configuration, drivers should make use of pmf(9) framework. Power can be applied and the interrupt handler should be established through this interface. dynamic configuration? she's flexible 💅

🌸 DMA SUPPORT 🌸

No additional support is provided for CardBus DMA beyond the facilities provided by the bus_dma(9) interface. that's it, that's the DMA tea ☕

💜 CODE REFERENCES 💜

The CardBus subsystem itself is implemented within the files sys/dev/cardbus/cardbus.c, sys/dev/cardbus/cardbus_map.c and sys/dev/cardbus/cardslot.c. The database for PCI devices is also used for known CardBus devices. For more details see pci(9). source files said "we're right here" 📂

🎀 SEE ALSO 🎀

⭐ HISTORY ⭐

The machine-independent Cardbus subsystem appeared in NetBSD 1.5. a classic, a legend, an icon 👑

shoutout to the Debian source, dated July 13, 2014, for serving us this CARDBUS(9) page 💖 periodt.

📦 where this page comes from