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freebsd-nq/sys/dev/uart/uart_cpu_i386.c

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The uart(4) driver is an universal driver for various UART hardware. It improves on sio(4) in the following areas: o Fully newbusified to allow for memory mapped I/O. This is a must for ia64 and sparc64, o Machine dependent code to take full advantage of machine and firm- ware specific ways to define serial consoles and/or debug ports. o Hardware abstraction layer to allow the driver to be used with various UARTs, such as the well-known ns8250 family of UARTs, the Siemens sab82532 or the Zilog Z8530. This is especially important for pc98 and sparc64 where it's common to have different UARTs, o The notion of system devices to unkludge low-level consoles and remote gdb ports and provides the mechanics necessary to support the keyboard on sparc64 (which is UART based). o The notion of a kernel interface so that a UART can be tied to something other than the well-known TTY interface. This is needed on sparc64 to present the user with a device and ioctl handling suitable for a keyboard, but also allows us to cleanly hide an UART when used as a debug port. Following is a list of features and bugs/flaws specific to the ns8250 family of UARTs as compared to their support in sio(4): o The uart(4) driver determines the FIFO size and automaticly takes advantages of larger FIFOs and/or additional features. Note that since I don't have sufficient access to 16[679]5x UARTs, hardware flow control has not been enabled. This is almost trivial to do, provided one can test. The downside of this is that broken UARTs are more likely to not work correctly with uart(4). The need for tunables or knobs may be large enough to warrant their creation. o The uart(4) driver does not share the same bumpy history as sio(4) and will therefore not provide the necessary hooks, tweaks, quirks or work-arounds to deal with once common hardware. To that extend, uart(4) supports a subset of the UARTs that sio(4) supports. The question before us is whether the subset is sufficient for current hardware. o There is no support for multiport UARTs in uart(4). The decision behind this is that uart(4) deals with one EIA RS232-C interface. Packaging of multiple interfaces in a single chip or on a single expansion board is beyond the scope of uart(4) and is now mostly left for puc(4) to deal with. Lack of hardware made it impossible to actually implement such a dependency other than is present for the dual channel SAB82532 and Z8350 SCCs. The current list of missing features is: o No configuration capabilities. A set of tunables and sysctls is being worked out. There are likely not going to be any or much compile-time knobs. Such configuration does not fit well with current hardware. o No support for the PPS API. This is partly dependent on the ability to configure uart(4) and partly dependent on having sufficient information to implement it properly. As usual, the manpage is present but lacks the attention the software has gotten.
2003-09-06 23:13:47 +00:00
/*
Introduce the hw.uart.console and hw.uart.dbgport environment variables to select a serial console and debug port (resp). On ia64 these replace the use of hints completely and take precedence over hints on alpha, amd64 and i386. On sparc64 these variables are not yet recognised. The reasons for introducing these variables are: 1. Hints have side-effects. They reserve the unit number for use by isa or acpi devices and therefore cannot be used to select a pci device. Also, the use of a unit number to select a device prior to bus enumeration is nonsense. The new variables have no side- effects and are not based on unit numbers. 2. Hints don't have the expression power to allow the sysadmin to select UARTs that are not legacy PC devices and need the support of compile-time constants to give the sysadmin some level of flexibility. The hw.uart.console and hw.uart.dbgport variables specify a list of attributes. An attribute is a tag-value pair, seperated by a colon. Attributes are seperated by a comma. Where possible, tags are the same as those in /etc/remote (only br and pa in practice). Details can be found in the manpage (not part of this commit). Not tested on: amd64, pc98
2004-03-20 02:14:02 +00:00
* Copyright (c) 2003, 2004 Marcel Moolenaar
The uart(4) driver is an universal driver for various UART hardware. It improves on sio(4) in the following areas: o Fully newbusified to allow for memory mapped I/O. This is a must for ia64 and sparc64, o Machine dependent code to take full advantage of machine and firm- ware specific ways to define serial consoles and/or debug ports. o Hardware abstraction layer to allow the driver to be used with various UARTs, such as the well-known ns8250 family of UARTs, the Siemens sab82532 or the Zilog Z8530. This is especially important for pc98 and sparc64 where it's common to have different UARTs, o The notion of system devices to unkludge low-level consoles and remote gdb ports and provides the mechanics necessary to support the keyboard on sparc64 (which is UART based). o The notion of a kernel interface so that a UART can be tied to something other than the well-known TTY interface. This is needed on sparc64 to present the user with a device and ioctl handling suitable for a keyboard, but also allows us to cleanly hide an UART when used as a debug port. Following is a list of features and bugs/flaws specific to the ns8250 family of UARTs as compared to their support in sio(4): o The uart(4) driver determines the FIFO size and automaticly takes advantages of larger FIFOs and/or additional features. Note that since I don't have sufficient access to 16[679]5x UARTs, hardware flow control has not been enabled. This is almost trivial to do, provided one can test. The downside of this is that broken UARTs are more likely to not work correctly with uart(4). The need for tunables or knobs may be large enough to warrant their creation. o The uart(4) driver does not share the same bumpy history as sio(4) and will therefore not provide the necessary hooks, tweaks, quirks or work-arounds to deal with once common hardware. To that extend, uart(4) supports a subset of the UARTs that sio(4) supports. The question before us is whether the subset is sufficient for current hardware. o There is no support for multiport UARTs in uart(4). The decision behind this is that uart(4) deals with one EIA RS232-C interface. Packaging of multiple interfaces in a single chip or on a single expansion board is beyond the scope of uart(4) and is now mostly left for puc(4) to deal with. Lack of hardware made it impossible to actually implement such a dependency other than is present for the dual channel SAB82532 and Z8350 SCCs. The current list of missing features is: o No configuration capabilities. A set of tunables and sysctls is being worked out. There are likely not going to be any or much compile-time knobs. Such configuration does not fit well with current hardware. o No support for the PPS API. This is partly dependent on the ability to configure uart(4) and partly dependent on having sufficient information to implement it properly. As usual, the manpage is present but lacks the attention the software has gotten.
2003-09-06 23:13:47 +00:00
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <machine/bus.h>
#include <dev/uart/uart.h>
#include <dev/uart/uart_cpu.h>
Introduce the hw.uart.console and hw.uart.dbgport environment variables to select a serial console and debug port (resp). On ia64 these replace the use of hints completely and take precedence over hints on alpha, amd64 and i386. On sparc64 these variables are not yet recognised. The reasons for introducing these variables are: 1. Hints have side-effects. They reserve the unit number for use by isa or acpi devices and therefore cannot be used to select a pci device. Also, the use of a unit number to select a device prior to bus enumeration is nonsense. The new variables have no side- effects and are not based on unit numbers. 2. Hints don't have the expression power to allow the sysadmin to select UARTs that are not legacy PC devices and need the support of compile-time constants to give the sysadmin some level of flexibility. The hw.uart.console and hw.uart.dbgport variables specify a list of attributes. An attribute is a tag-value pair, seperated by a colon. Attributes are seperated by a comma. Where possible, tags are the same as those in /etc/remote (only br and pa in practice). Details can be found in the manpage (not part of this commit). Not tested on: amd64, pc98
2004-03-20 02:14:02 +00:00
bus_space_tag_t uart_bus_space_io = I386_BUS_SPACE_IO;
bus_space_tag_t uart_bus_space_mem = I386_BUS_SPACE_MEM;
Remove the assumption that a bus_space_handle_t is an I/O address from the SAB82532 and the Z8530 hardware drivers by introducing uart_cpu_busaddr(). The assumption is not true on pc98 where bus_space_handle_t is a pointer to a structure. The uart_cpu_busaddr() function will return the bus address corresponding the tag and handle given to it by the BAS. WARNING: the intend of the function is STRICTLY to allow hardware drivers to determine which logical channel they control and is NOT to be used for actual I/O. It is therefore EXPLICITLY allowed that uart_cpu_busaddr() returns only the lower 8 bits of the address and garbage in all other bits. No mistakes...
2003-09-07 21:51:03 +00:00
int
uart_cpu_eqres(struct uart_bas *b1, struct uart_bas *b2)
{
return ((b1->bsh == b2->bsh && b1->bst == b2->bst) ? 1 : 0);
}
The uart(4) driver is an universal driver for various UART hardware. It improves on sio(4) in the following areas: o Fully newbusified to allow for memory mapped I/O. This is a must for ia64 and sparc64, o Machine dependent code to take full advantage of machine and firm- ware specific ways to define serial consoles and/or debug ports. o Hardware abstraction layer to allow the driver to be used with various UARTs, such as the well-known ns8250 family of UARTs, the Siemens sab82532 or the Zilog Z8530. This is especially important for pc98 and sparc64 where it's common to have different UARTs, o The notion of system devices to unkludge low-level consoles and remote gdb ports and provides the mechanics necessary to support the keyboard on sparc64 (which is UART based). o The notion of a kernel interface so that a UART can be tied to something other than the well-known TTY interface. This is needed on sparc64 to present the user with a device and ioctl handling suitable for a keyboard, but also allows us to cleanly hide an UART when used as a debug port. Following is a list of features and bugs/flaws specific to the ns8250 family of UARTs as compared to their support in sio(4): o The uart(4) driver determines the FIFO size and automaticly takes advantages of larger FIFOs and/or additional features. Note that since I don't have sufficient access to 16[679]5x UARTs, hardware flow control has not been enabled. This is almost trivial to do, provided one can test. The downside of this is that broken UARTs are more likely to not work correctly with uart(4). The need for tunables or knobs may be large enough to warrant their creation. o The uart(4) driver does not share the same bumpy history as sio(4) and will therefore not provide the necessary hooks, tweaks, quirks or work-arounds to deal with once common hardware. To that extend, uart(4) supports a subset of the UARTs that sio(4) supports. The question before us is whether the subset is sufficient for current hardware. o There is no support for multiport UARTs in uart(4). The decision behind this is that uart(4) deals with one EIA RS232-C interface. Packaging of multiple interfaces in a single chip or on a single expansion board is beyond the scope of uart(4) and is now mostly left for puc(4) to deal with. Lack of hardware made it impossible to actually implement such a dependency other than is present for the dual channel SAB82532 and Z8350 SCCs. The current list of missing features is: o No configuration capabilities. A set of tunables and sysctls is being worked out. There are likely not going to be any or much compile-time knobs. Such configuration does not fit well with current hardware. o No support for the PPS API. This is partly dependent on the ability to configure uart(4) and partly dependent on having sufficient information to implement it properly. As usual, the manpage is present but lacks the attention the software has gotten.
2003-09-06 23:13:47 +00:00
int
uart_cpu_getdev(int devtype, struct uart_devinfo *di)
{
unsigned int i, ivar;
Introduce the hw.uart.console and hw.uart.dbgport environment variables to select a serial console and debug port (resp). On ia64 these replace the use of hints completely and take precedence over hints on alpha, amd64 and i386. On sparc64 these variables are not yet recognised. The reasons for introducing these variables are: 1. Hints have side-effects. They reserve the unit number for use by isa or acpi devices and therefore cannot be used to select a pci device. Also, the use of a unit number to select a device prior to bus enumeration is nonsense. The new variables have no side- effects and are not based on unit numbers. 2. Hints don't have the expression power to allow the sysadmin to select UARTs that are not legacy PC devices and need the support of compile-time constants to give the sysadmin some level of flexibility. The hw.uart.console and hw.uart.dbgport variables specify a list of attributes. An attribute is a tag-value pair, seperated by a colon. Attributes are seperated by a comma. Where possible, tags are the same as those in /etc/remote (only br and pa in practice). Details can be found in the manpage (not part of this commit). Not tested on: amd64, pc98
2004-03-20 02:14:02 +00:00
/* Check the environment. */
if (uart_getenv(devtype, di) == 0)
return (0);
The uart(4) driver is an universal driver for various UART hardware. It improves on sio(4) in the following areas: o Fully newbusified to allow for memory mapped I/O. This is a must for ia64 and sparc64, o Machine dependent code to take full advantage of machine and firm- ware specific ways to define serial consoles and/or debug ports. o Hardware abstraction layer to allow the driver to be used with various UARTs, such as the well-known ns8250 family of UARTs, the Siemens sab82532 or the Zilog Z8530. This is especially important for pc98 and sparc64 where it's common to have different UARTs, o The notion of system devices to unkludge low-level consoles and remote gdb ports and provides the mechanics necessary to support the keyboard on sparc64 (which is UART based). o The notion of a kernel interface so that a UART can be tied to something other than the well-known TTY interface. This is needed on sparc64 to present the user with a device and ioctl handling suitable for a keyboard, but also allows us to cleanly hide an UART when used as a debug port. Following is a list of features and bugs/flaws specific to the ns8250 family of UARTs as compared to their support in sio(4): o The uart(4) driver determines the FIFO size and automaticly takes advantages of larger FIFOs and/or additional features. Note that since I don't have sufficient access to 16[679]5x UARTs, hardware flow control has not been enabled. This is almost trivial to do, provided one can test. The downside of this is that broken UARTs are more likely to not work correctly with uart(4). The need for tunables or knobs may be large enough to warrant their creation. o The uart(4) driver does not share the same bumpy history as sio(4) and will therefore not provide the necessary hooks, tweaks, quirks or work-arounds to deal with once common hardware. To that extend, uart(4) supports a subset of the UARTs that sio(4) supports. The question before us is whether the subset is sufficient for current hardware. o There is no support for multiport UARTs in uart(4). The decision behind this is that uart(4) deals with one EIA RS232-C interface. Packaging of multiple interfaces in a single chip or on a single expansion board is beyond the scope of uart(4) and is now mostly left for puc(4) to deal with. Lack of hardware made it impossible to actually implement such a dependency other than is present for the dual channel SAB82532 and Z8350 SCCs. The current list of missing features is: o No configuration capabilities. A set of tunables and sysctls is being worked out. There are likely not going to be any or much compile-time knobs. Such configuration does not fit well with current hardware. o No support for the PPS API. This is partly dependent on the ability to configure uart(4) and partly dependent on having sufficient information to implement it properly. As usual, the manpage is present but lacks the attention the software has gotten.
2003-09-06 23:13:47 +00:00
/*
* Scan the hints. We only try units 0 to 3 (inclusive). This
* covers the ISA legacy where 4 UARTs had their resources
* predefined.
*/
for (i = 0; i < 4; i++) {
if (resource_int_value("uart", i, "flags", &ivar))
continue;
if (devtype == UART_DEV_CONSOLE && !UART_FLAGS_CONSOLE(ivar))
continue;
if (devtype == UART_DEV_DBGPORT && !UART_FLAGS_DBGPORT(ivar))
continue;
/*
* We have a possible device. Make sure it's enabled and
* that we have an I/O port.
*/
if (resource_int_value("uart", i, "disabled", &ivar) == 0 &&
ivar != 0)
continue;
if (resource_int_value("uart", i, "port", &ivar) != 0 ||
ivar == 0)
continue;
/*
* Got it. Fill in the instance and return it. We only have
* ns8250 and successors on i386.
*/
di->ops = uart_ns8250_ops;
Revert the introduction of iobase in struct uart_bas. Both the SAB82532 and the Z8530 drivers used the I/O address as a quick and dirty way to determine which channel they operated on, but formalizing this by introducing iobase is not a solution. How for example would a driver know which channel it controls for a multi-channel UART that only has a single I/O range? Instead, add an explicit field, called chan, to struct uart_bas that holds the channel within a device, or 0 otherwise. The chan field is initialized both by the system device probing (i.e. a system console) or it is passed down to uart_bus_probe() by any of the bus front-ends. As such, it impacts all platforms and bus drivers and makes it a rather large commit. Remove the use of iobase in uart_cpu_eqres() for pc98. It is expected that platforms have the capability to compare tag and handle pairs for equality; as to determine whether two pairs access the same device or not. The use of iobase for pc98 makes it impossible to formalize this and turn it into a real newbus function later. This commit reverts uart_cpu_eqres() for pc98 to an unimplemented function. It has to be reimplemented using only the tag and handle fields in struct uart_bas. Rewrite the SAB82532 and Z8530 drivers to use the chan field in struct uart_bas. Remove the IS_CHANNEL_A and IS_CHANNEL_B macros. We don't need to abstract anything anymore. Discussed with: nyan Tested on: i386, ia64, sparc64
2003-09-26 05:14:56 +00:00
di->bas.chan = 0;
Introduce the hw.uart.console and hw.uart.dbgport environment variables to select a serial console and debug port (resp). On ia64 these replace the use of hints completely and take precedence over hints on alpha, amd64 and i386. On sparc64 these variables are not yet recognised. The reasons for introducing these variables are: 1. Hints have side-effects. They reserve the unit number for use by isa or acpi devices and therefore cannot be used to select a pci device. Also, the use of a unit number to select a device prior to bus enumeration is nonsense. The new variables have no side- effects and are not based on unit numbers. 2. Hints don't have the expression power to allow the sysadmin to select UARTs that are not legacy PC devices and need the support of compile-time constants to give the sysadmin some level of flexibility. The hw.uart.console and hw.uart.dbgport variables specify a list of attributes. An attribute is a tag-value pair, seperated by a colon. Attributes are seperated by a comma. Where possible, tags are the same as those in /etc/remote (only br and pa in practice). Details can be found in the manpage (not part of this commit). Not tested on: amd64, pc98
2004-03-20 02:14:02 +00:00
di->bas.bst = uart_bus_space_io;
Use bus_space_map() to initialize a bus_handle.
2003-09-23 08:38:49 +00:00
if (bus_space_map(di->bas.bst, ivar, 8, 0, &di->bas.bsh) != 0)
Don't return to search another ports even if bus_space_map() fails.
2003-09-23 13:03:22 +00:00
continue;
The uart(4) driver is an universal driver for various UART hardware. It improves on sio(4) in the following areas: o Fully newbusified to allow for memory mapped I/O. This is a must for ia64 and sparc64, o Machine dependent code to take full advantage of machine and firm- ware specific ways to define serial consoles and/or debug ports. o Hardware abstraction layer to allow the driver to be used with various UARTs, such as the well-known ns8250 family of UARTs, the Siemens sab82532 or the Zilog Z8530. This is especially important for pc98 and sparc64 where it's common to have different UARTs, o The notion of system devices to unkludge low-level consoles and remote gdb ports and provides the mechanics necessary to support the keyboard on sparc64 (which is UART based). o The notion of a kernel interface so that a UART can be tied to something other than the well-known TTY interface. This is needed on sparc64 to present the user with a device and ioctl handling suitable for a keyboard, but also allows us to cleanly hide an UART when used as a debug port. Following is a list of features and bugs/flaws specific to the ns8250 family of UARTs as compared to their support in sio(4): o The uart(4) driver determines the FIFO size and automaticly takes advantages of larger FIFOs and/or additional features. Note that since I don't have sufficient access to 16[679]5x UARTs, hardware flow control has not been enabled. This is almost trivial to do, provided one can test. The downside of this is that broken UARTs are more likely to not work correctly with uart(4). The need for tunables or knobs may be large enough to warrant their creation. o The uart(4) driver does not share the same bumpy history as sio(4) and will therefore not provide the necessary hooks, tweaks, quirks or work-arounds to deal with once common hardware. To that extend, uart(4) supports a subset of the UARTs that sio(4) supports. The question before us is whether the subset is sufficient for current hardware. o There is no support for multiport UARTs in uart(4). The decision behind this is that uart(4) deals with one EIA RS232-C interface. Packaging of multiple interfaces in a single chip or on a single expansion board is beyond the scope of uart(4) and is now mostly left for puc(4) to deal with. Lack of hardware made it impossible to actually implement such a dependency other than is present for the dual channel SAB82532 and Z8350 SCCs. The current list of missing features is: o No configuration capabilities. A set of tunables and sysctls is being worked out. There are likely not going to be any or much compile-time knobs. Such configuration does not fit well with current hardware. o No support for the PPS API. This is partly dependent on the ability to configure uart(4) and partly dependent on having sufficient information to implement it properly. As usual, the manpage is present but lacks the attention the software has gotten.
2003-09-06 23:13:47 +00:00
di->bas.regshft = 0;
di->bas.rclk = 0;
if (resource_int_value("uart", i, "baud", &ivar) != 0)
ivar = 0;
di->baudrate = ivar;
di->databits = 8;
di->stopbits = 1;
di->parity = UART_PARITY_NONE;
return (0);
}
return (ENXIO);
}
- Introduce an uart_cpu_identify() which is implemented in uart_cpu_<arch>.c and that can be used as an identify function for all kinds of busses on a certain platform. Expect for sparc64 these are only stubs right now. [1] - For sparc64, add code to its uart_cpu_identify() for registering the on- board ISA UARTs and their resources based on information obtained from Open Firmware. It would be better if this would be done in the OFW ISA code. However, due to the common FreeBSD ISA code and PNP-IDs not always being present in the properties of the ISA nodes there seems to be no good way to implement that. Therefore special casing UARTs as the sole really relevant ISA devices on sparc64 seemed reasonable. [2] Approved by: marcel Discussed with: marcel [1], tmm [2] Tested by: make universe
2004-08-14 23:54:27 +00:00
void
uart_cpu_identify(driver_t *driver, device_t parent)
{
}
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