src/sys/dev/uart, branch releng/14.4

uart: Add ns8250 ACPI entry for SPCR rev 2

2026-02-12T21:24:22Z

This is an MFC "in spirit" of a685a263b803; the code in this area has been significantly restructured between 14.x and 15.x, but the general concept of adding ACPI_DBG2_16550_WITH_GAS (aka 0x12) as a recognized flavour of ns8250 UART which can be configured via SPCR remains. Approved by: re (cperciva) Reviewed by: imp Tested by: David Woodhouse Sponsored by: Amazon Differential Revision: https://reviews.freebsd.org/D55173 (cherry picked from commit 1dd5b197b72357dfe50d6da2c9cb5b34bf4bf64b)

ns8250: use LSR_THRE instead of LSR_TEMT for checking tx flush

2025-06-27T07:37:55Z

LSR_TEMT bit is set if both transmit hold and shift registers are empty, but the flush command flushes only the hold register. While here, update the diagnostic message to report which registers could not be flushed. (cherry picked from commit 0d2fd5b99c95329085d0700a4dd38507a054a50d)

uart: Add support for Brainboxes / Intashield serial cards.

2025-01-11T08:09:41Z

PR: 283226 Reported by: Cameron Williams (cherry picked from commit 41b30bbc1a57b60afee9acdd6ad240c92ef13790)

dev/uart: Add APMC0D08 as found in the Intel E2100

2024-09-02T08:48:54Z

This uart has the requirement for 32-bit sized and aligned memory accesses. It is also described in the Serial Port Console Redirection Table (SPCR) with a different interface type value. Reviewed by: imp Sponsored by: Arm Ltd Differential Revision: https://reviews.freebsd.org/D45834 (cherry picked from commit 9840598aa31f2a89272f5bef6545e316f254f0c6)

uart: Split out initilisation of the acpi devinfo

2024-09-02T08:43:42Z

Split out the common parts of building the uart devinfo from ACPI tables from the SPCR parser. This will be used when we support the DBG2 table to find the debug uart to be used by the kernel gdb stub. Reviewed by: imp Sponsored by: Arm Ltd Differential Revision: https://reviews.freebsd.org/D44357 (cherry picked from commit 473c0b44ae8c51b2aebc51887714b2ed14de50bf)

uart: Use device_set_descf()

2024-06-09T13:37:58Z

No functional change intended. MFC after: 1 week (cherry picked from commit 66d2d42a1f26a6ef868d7d46f87d6fad0bc099aa)

Add support for Intel Atom S1200 UART

2024-04-24T23:57:55Z

PR: 278316 Signed-off-by: Henrich Hartzer Reviewed by: imp Pull Request: https://github.com/freebsd/freebsd-src/pull/1164 (cherry picked from commit 1f2776e123603042944aad9f41ceb46b5b28d8ae)

dev/uart: Support 8-byte register access

2024-02-19T13:17:56Z

While we only support 4-byte registers in the uart code the physical access may be to an 8-byte register. Support this as an option on non-i386. On i386 we lack the needed 8-byte bus_space functions. ACPI has an option for 8-byte register io width, and FDT can be given any size. Support these sizes, even if we don't expect to see hardware with an 8-byte io width. Reviewed by: imp Sponsored by: Arm Ltd Differential Revision: https://reviews.freebsd.org/D43374 (cherry picked from commit a9fc9d6d15f006feb6d7ddb036e020d5f9d19fce)

uart(4): Honor hardware state of NS8250-class for tsw_busy

2024-01-18T20:14:46Z

In 9750d9e5, I brought the equivalent of the TS_BUSY flag back in a mostly hardware-agnostic way in order to fix tty_drain() and, thus, TIOCDRAIN for UARTs with TX FIFOs. This proved to be sufficient for fixing the regression reported. So in light of the release cycle of FreeBSD 10.3, I decided that this change was be good enough for the time being and opted to go with the smallest possible yet generic (for all UARTs driven by uart(4)) solution addressing the problem at hand. However, at least for the NS8250-class the above isn't a complete fix as these UARTs only trigger an interrupt when the TX FIFO became empty. At this point, there still can be an outstanding character left in the transmit shift register as indicated via the LSR. Thus, this change adds the 3rd (besides the tty(4) and generic uart(4) bits) part I had in my tree ever since, adding a uart_txbusy method to be queried in addition for tsw_busy and hooking it up as appropriate for the NS8250-class. As it turns out, the exact equivalent of this 3rd part later on was implemented for uftdi(4) in 9ad221a5. While at it, explain the rational behind the deliberately missing locking in uart_tty_busy() (also applying to the generic sc_txbusy testing already present). (cherry picked from commit 353e4c5a068d06b0d6dcfa9eb736ecb16e9eae45)

sys: Remove $FreeBSD$: one-line sh pattern

2023-08-16T17:54:58Z

Remove /^\s*#[#!]?\s*\$FreeBSD\$.*$\n/