powerpc: Drop MPC5200 LocalPlus bus FIFO driver

While mpc5200b.dtsi contains a device that this driver can bind to, the
only purpose of a bound device is to be used by the four exported functions
mpc52xx_lpbfifo_submit(), mpc52xx_lpbfifo_abort(), mpc52xx_lpbfifo_poll()
and mpc52xx_lpbfifo_start_xfer(). However there are no callers to this
function and so the driver is effectively superfluous and can be deleted.
Also drop some defines and a struct from <asm/mpc52xx.h> that are unused
now together with the declarations of the four mentioned functions.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230413061642.kqkor4wkt7lp2mhp@pengutronix.de

powerpc: Remove asm/prom.h from asm/mpc52xx.h and asm/pci.h

asm/pci.h and asm/mpc52xx.h don't need asm/prom.h

Declare struct device_node locally to avoid including of.h

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Add missing include of prom.h to of_rtc.c]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/cf5243343e2364c2b40f22ee5ad9a6e2453d1121.1657264228.git.christophe.leroy@csgroup.eu

powerpc/52xx: Remove dead code, i.e. mpc52xx_get_xtal_freq()

It seems mpc52xx_get_xtal_freq() is not used anywhere. Remove dead code.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Wolfram Sang <wsa@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220507100147.5802-1-andriy.shevchenko@linux.intel.com

powerpc/52xx: Add missing functions prototypes

The function prototypes were declared within a `#ifdef CONFIG_PPC_LITE5200`
block which would prevent them from being visible when compiling
`mpc52xx_pm.c`. Move the prototypes outside of the `#ifdef` block to fix
the following warnings treated as errors with W=1:

arch/powerpc/platforms/52xx/mpc52xx_pm.c:58:5: error: no previous prototype for ‘mpc52xx_pm_prepare’ [-Werror=missing-prototypes]
arch/powerpc/platforms/52xx/mpc52xx_pm.c:113:5: error: no previous prototype for ‘mpc52xx_pm_enter’ [-Werror=missing-prototypes]
arch/powerpc/platforms/52xx/mpc52xx_pm.c:181:6: error: no previous prototype for ‘mpc52xx_pm_finish’ [-Werror=missing-prototypes]

Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc: Make ppc_md.{halt, restart} __noreturn

powernv marks it's halt and restart calls as __noreturn. However,
ppc_md does not have this annotation. Add the annotation to ppc_md,
and then to every halt/restart function that is missing it.

Additionally, I have verified that all of these functions do not
return. Occasionally I have added a spin loop to be sure.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/mpc52xx_lpbfifo: optionally defer fifo transfer start

Currently fifo transfer is started when submitting a transfer
request. Add posibility to defer the fifo transfer and start it
later by calling additional function. This change is backward
compatible, the behaviour of mpc52xx_lpbfifo_submit() is the same
for previous driver users, so there is no need to adapt them.

Signed-off-by: Anatolij Gustschin <agust@denx.de>

powerpc/5200: add mpc5200_psc_ac97_gpio_reset

Work around a silicon bug in the ac97 reset functionality of the
mpc5200(b). The implementation of the ac97 "cold" reset is flawed.
If the sync and output lines are high when reset is asserted the
attached ac97 device may go into test mode. Avoid this by
reconfiguring the psc to gpio mode and generating the reset manually.

From MPC5200B User's Manual:
"Some AC97 devices goes to a test mode, if the Sync line is high
during the Res line is low (reset phase). To avoid this behavior the
Sync line must be also forced to zero during the reset phase. To do
that, the pin muxing should switch to GPIO mode and the GPIO control
register should be used to control the output lines."

Signed-off-by: Eric Millbrandt <emillbrandt@dekaresearch.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

mpc52xx/wdt: merge WDT code into the GPT driver

Merge the WDT code into the GPT interface.

Signed-off-by: Albrecht Dreß <albrecht.dress@arcor.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

mpc5200/gpt: tiny fix for gpt period limitation

This patch changes the period parameter of mpc52xx_gpt_start_timer to
a u64 to support larger timeout periods.

Signed-off-by: Albrecht Dreß <albrecht.dress@arcor.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

powerpc/5200: add LocalPlus bus FIFO device driver

This is a driver for the FIFO device on the LocalPlus bus on an mpc5200 system.
The driver supports programmed I/O through the FIFO as well as setting up DMA
via the BestComm engine through the FIFO.

Signed-off-by: John Bonesio <bones@secretlab.ca>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

powerpc/5200: add general purpose timer API for the MPC5200

This patch adds an interface for controlling the timer function of the
MPC5200 GPT devices.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

powerpc/5xxx: Add common mpc5xxx_get_bus_frequency() function

So far, MPC512x used mpc512x_find_ips_freq() to get the bus frequency,
while MPC52xx used mpc52xx_find_ipb_freq(). Despite the different
clock names (IPS vs. IPB) the code was identical.

Use common code for both processor families.

Signed-off-by: Wolfgang Denk <wd@denx.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

powerpc/5200: add function to return external clock frequency

This patch adds the utility function mpc52xx_get_xtal_freq() to get
the frequency of the external oscillator clock connected to the pin
SYS_XTAL_IN. The MSCAN may us it as clock source. Unfortunately, this
value is not available from the FDT blob, but it can be determined
from the IPB frequency.

Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

powerpc/mpc5200: Document and tidy irq driver

This patch adds documentation to the mpc5200 interrupt controller
driver and cleans up some minor coding conventions. It also moves the
contents of mpc52xx_pic.h into the driver proper (except for a small
common bit that is moved to the common mpc52xx.h) because the
information encoded there is not required by any other part of kernel
code. Finally for code readability sake, the L2_OFFSET shift value
is removed because the code using it resolves to a noop.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

powerpc: Move include files to arch/powerpc/include/asm

from include/asm-powerpc. This is the result of a

mkdir arch/powerpc/include/asm
git mv include/asm-powerpc/* arch/powerpc/include/asm

Followed by a few documentation/comment fixups and a couple of places
where <asm-powepc/...> was being used explicitly. Of the latter only
one was outside the arch code and it is a driver only built for powerpc.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>