All of lore.kernel.org
 help / color / mirror / Atom feed
* [RFC PATCH 0/3] serial: uartps: Add run time support for more IPs than hardcoded 2
@ 2018-04-26 14:08 ` Michal Simek
  0 siblings, 0 replies; 22+ messages in thread
From: Michal Simek @ 2018-04-26 14:08 UTC (permalink / raw)
  To: linux-kernel, monstr, gnomes, Alexander Graf
  Cc: devicetree, Jiri Slaby, Greg Kroah-Hartman, Rob Herring,
	linux-serial, Frank Rowand, linux-arm-kernel

Hi,

this series is trying to address discussion I had with Alan in past
https://patchwork.kernel.org/patch/9738445/.

It is moving uart_register_driver() to probe function like it is done in
pl011 driver.
And also introducing new function for alias compatibility checking to
resolve cases where some IPs have alias and some of them not.
This case is detected in pl011_probe_dt_alias() but not properly solved.

Also keep status of free ids/minor numbers in bitmap to know what's the
next unallocated number.

The same solution can be used in pl011, uart16550 and uartlite to really
get unified kernel.

Tested on these use cases:
Notes:
ff000000 is the first PS uart listed in dtsi
ff010000 is the second PS uart listed in dtsi

Standard zcu102 setting
		serial0 = &uart0;
		serial1 = &uart1;
[    0.196628] ff000000.serial: ttyPS0 at MMIO 0xff000000 (irq = 33,
base_baud = 6250000) is a xuartps
[    0.642542] ff010000.serial: ttyPS1 at MMIO 0xff010000 (irq = 34,
base_baud = 6250000) is a xuartps

Swapped zcu102 setting
		serial0 = &uart1;
		serial1 = &uart0;
[    0.196472] ff000000.serial: ttyPS1 at MMIO 0xff000000 (irq = 33,
base_baud = 6250000) is a xuartps
[    0.196824] ff010000.serial: ttyPS0 at MMIO 0xff010000 (irq = 34,
base_baud = 6250000) is a xuartps

uart0 on alias higher then MAX uart ports
		serial0 = &uart1;
		serial200 = &uart0;
[    0.176793] ff000000.serial: ttyPS200 at MMIO 0xff000000 (irq = 33,
base_baud = 6250000) is a xuartps
[    0.177288] ff010000.serial: ttyPS0 at MMIO 0xff010000 (irq = 34,
base_baud = 6250000) is a xuartps

Both uarts on higher aliases
		serial1 = &uart1;
		serial2 = &uart0;
[    0.196470] ff000000.serial: ttyPS2 at MMIO 0xff000000 (irq = 33,
base_baud = 6250000) is a xuartps
[    0.196823] ff010000.serial: ttyPS1 at MMIO 0xff010000 (irq = 34,
base_baud = 6250000) is a xuartps

uart0 not listed but it is probed first that's why should be ttyPS0 but
there is uart1 via alias
		serial0 = &uart1;
[    0.176656] xuartps ff000000.serial: No serial alias passed. Using
the first free id
[    0.176671] xuartps ff000000.serial: Validate id 0
[    0.176680] xuartps ff000000.serial: The empty id is 0
[    0.176692] xuartps ff000000.serial: ID 0 already taken - skipped
[    0.176701] xuartps ff000000.serial: Validate id 1
[    0.176710] xuartps ff000000.serial: The empty id is 1
[    0.176719] xuartps ff000000.serial: Selected ID 1 allocation passed
[    0.176760] ff000000.serial: ttyPS1 at MMIO 0xff000000 (irq = 33,
base_baud = 6250000) is a xuartps
[    0.177104] ff010000.serial: ttyPS0 at MMIO 0xff010000 (irq = 34,
base_baud = 6250000) is a xuartps

uart0 not listed but it is probed first that's why should be ttyPS0
		serial1 = &uart1;
[    0.176661] xuartps ff000000.serial: No serial alias passed. Using
the first free id
[    0.176676] xuartps ff000000.serial: Validate id 0
[    0.176686] xuartps ff000000.serial: The empty id is 0
[    0.176696] xuartps ff000000.serial: Selected ID 0 allocation passed
[    0.176737] ff000000.serial: ttyPS0 at MMIO 0xff000000 (irq = 33,
base_baud = 6250000) is a xuartps
[    0.177069] ff010000.serial: ttyPS1 at MMIO 0xff010000 (irq = 34,
base_baud = 6250000) is a xuartps

uarts not listed in aliases list
[    0.176673] xuartps ff000000.serial: No serial alias passed. Using
the first free id
[    0.176687] xuartps ff000000.serial: Validate id 0
[    0.176697] xuartps ff000000.serial: The empty id is 0
[    0.176707] xuartps ff000000.serial: Selected ID 0 allocation passed
[    0.176746] ff000000.serial: ttyPS0 at MMIO 0xff000000 (irq = 33,
base_baud = 6250000) is a xuartps
[    0.177057] xuartps ff010000.serial: No serial alias passed. Using
the first free id
[    0.177070] xuartps ff010000.serial: Validate id 0
[    0.177079] xuartps ff010000.serial: The empty id is 0
[    0.177089] xuartps ff010000.serial: Selected ID 0 allocation failed
[    0.177098] xuartps ff010000.serial: Validate id 1
[    0.177107] xuartps ff010000.serial: The empty id is 1
[    0.177116] xuartps ff010000.serial: Selected ID 1 allocation passed
[    0.177149] ff010000.serial: ttyPS1 at MMIO 0xff010000 (irq = 34,
base_baud = 6250000) is a xuartps

Thanks,
Michal


Michal Simek (3):
  of: base: Introduce of_alias_check_id() to check alias IDs
  serial: uartps: Move register to probe based on run time detection
  serial: uartps: Change uart ports allocation

 drivers/of/base.c                  |  49 +++++++++++
 drivers/tty/serial/xilinx_uartps.c | 128 +++++++++++++++++++++++------
 include/linux/of.h                 |   2 +
 3 files changed, 153 insertions(+), 26 deletions(-)

-- 
2.17.0


^ permalink raw reply	[flat|nested] 22+ messages in thread

end of thread, other threads:[~2018-05-09 12:09 UTC | newest]

Thread overview: 22+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-04-26 14:08 [RFC PATCH 0/3] serial: uartps: Add run time support for more IPs than hardcoded 2 Michal Simek
2018-04-26 14:08 ` Michal Simek
2018-04-26 14:08 ` [RFC PATCH 1/3] of: base: Introduce of_alias_check_id() to check alias IDs Michal Simek
2018-04-27  2:39   ` Rob Herring
2018-04-27  6:10     ` Michal Simek
2018-04-27  6:10       ` Michal Simek
2018-04-27 13:02       ` Rob Herring
2018-04-27 14:14         ` Michal Simek
2018-04-27 14:14           ` Michal Simek
2018-04-27 15:05           ` Rob Herring
2018-04-27 21:58           ` Alexander Graf
2018-04-30 13:44             ` Rob Herring
2018-04-26 14:08 ` [RFC PATCH 2/3] serial: uartps: Move register to probe based on run time detection Michal Simek
2018-04-26 14:08   ` Michal Simek
2018-04-26 14:08 ` [RFC PATCH 3/3] serial: uartps: Change uart ports allocation Michal Simek
2018-04-26 14:08   ` Michal Simek
2018-05-05 13:10 ` [RFC PATCH 0/3] serial: uartps: Add run time support for more IPs than hardcoded 2 Maarten Brock
2018-05-05 13:10   ` Maarten Brock
2018-05-05 13:10   ` Maarten Brock
2018-05-09 12:09   ` Michal Simek
2018-05-09 12:09     ` Michal Simek
2018-05-09 12:09     ` Michal Simek

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.