soc: qcom: icc-bwmon: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.
To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new() which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Link: https://lore.kernel.org/r/20230925095532.1984344-19-u.kleine-koenig@pengutronix.de
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

soc: qcom: Explicitly include correct DT includes

The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it as merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.

Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230714175142.4067795-1-robh@kernel.org
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

soc: qcom: icc-bwmon: Set default thresholds dynamically

Currently we use predefined initial threshold values. This works, but
does not really scale well with more and more SoCs gaining bwmon support,
as the necessary kickoff values may differ between platforms due to memory
type and/or controller setup.
All of the data we need for that is already provided in the device tree,
anyway.

Change the thresholds to:
* low = 0 (as we've been doing up until now)
* med = high = BW_MIN

Throughput going below the med threshold nudges bwmon into signaling
that we should slow down (e.g. if we inherited too high bandwidth
from the bootloader).

Throughput going above the high threshold nudges bwmon into signaling
that we should speed up so as not to choke the bus traffic due to
insufficient transfer rates.

F_MIN is a perfect initial value for both of these cases - if we go
above it (and there's a 99.99% chance it'll happen at boot time), we
should definitely make the memory go faster, whereas if we go below it,
we should slow down, no matter what performance state we were at before
(it's only possible for them to be >= FMIN).

This only changes the values programmed at probe time, as high and med
thresholds are updated at interrupt, also based on the OPP table from DT.

Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Reviewed-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230610-topic-bwmon_opp-v2-1-0d25c1ce7dca@linaro.org
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

soc: qcom: icc-bwmon: Fix MSM8998 count unit

MSM8998's BWMON counts in megabytes. Fix it.

Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230531-topic-msm8998-bwmon-v1-1-454f9d550ee5@linaro.org

soc: qcom: icc-bwmon: fix incorrect error code passed to dev_err_probe()

Pass to dev_err_probe() PTR_ERR from actual dev_pm_opp_find_bw_floor()
call which failed, instead of previous ret which at this point is 0.
Failure of dev_pm_opp_find_bw_floor() would result in prematurely ending
the probe with success.

Fixes smatch warnings:

drivers/soc/qcom/icc-bwmon.c:776 bwmon_probe() warn: passing zero to 'dev_err_probe'
drivers/soc/qcom/icc-bwmon.c:781 bwmon_probe() warn: passing zero to 'dev_err_probe'

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Link: https://lore.kernel.org/r/202305131657.76XeHDjF-lkp@intel.com/
Cc: <stable@vger.kernel.org>
Fixes: b9c2ae6cac40 ("soc: qcom: icc-bwmon: Add bandwidth monitoring driver")
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230513111747.132532-1-krzysztof.kozlowski@linaro.org

soc: qcom: icc-bwmon: Handle global registers correctly

The BWMON hardware has two sets of registers: one for the monitor itself
and one called "global". It has what seems to be some kind of a head
switch and an interrupt control register. It's usually 0x200 in size.

On fairly recent SoCs (with the starting point seemingly being moving
the OSM programming to the firmware) these two register sets are
contiguous and overlapping, like this (on sm8450):

/* notice how base.start == global_base.start+0x100 */
reg = <0x90b6400 0x300>, <0x90b6300 0x200>;
reg-names = "base", "global_base";

Which led to some confusion and the assumption that since the
"interesting" global registers begin right after global_base+0x100,
there's no need to map two separate regions and one can simply subtract
0x100 from the offsets.

This is however not the case for anything older than SDM845, as the
global region can appear in seemingly random spots on the register map.

Handle the case where the global registers are mapped separately to allow
proper functioning of BWMONv4 on MSM8998 and older. Add specific
compatibles for 845, 8280xp, 7280 and 8550 (all of which use the single
reg space scheme) to keep backwards compatibility with old DTs.

Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230304-topic-ddr_bwmon-v3-3-77a050c2fbda@linaro.org

soc: qcom: icc-bwmon: Remove unused struct member

bwmon->regmap was never used, as the regmap for bwmon is registered
through devres and accessed through bwmon's regmap_field members.
Remove it

Fixes: ec63dcd3c863 ("soc: qcom: icc-bwmon: use regmap and prepare for BWMON v5")
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230304-topic-ddr_bwmon-v3-2-77a050c2fbda@linaro.org

soc: qcom: icc-bwmon: force clear counter/irq registers

In some SoCs we have to force clear the counter/irq clear registers as
they are not self clearing after they are written into.
sc7280 seems to be one such SoC, handle this with a quirk flag.

Signed-off-by: Rajendra Nayak <quic_rjendra@quicinc.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20220902043511.17130-4-quic_rjendra@quicinc.com

soc: qcom: icc-bwmon: add support for sc7280 LLCC BWMON

Add support for sc7280 BWMON instance measuring traffic between LLCC and
memory with the v5 register layout.

Signed-off-by: Rajendra Nayak <quic_rjendra@quicinc.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20220902043511.17130-3-quic_rjendra@quicinc.com

soc: qcom: icc-bwmon: remove redundant ret variable

Return value from devm_regmap_field_bulk_alloc() directly
instead of taking this in another redundant variable.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Jinpeng Cui <cui.jinpeng2@zte.com.cn>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20220823133620.211902-1-cui.jinpeng2@zte.com.cn

soc: qcom: icc-bwmon: add support for SDM845 LLCC BWMON

The SDM845 comes with few instances of Bandwidth Monitor. The already
supported one monitors traffic between CPU and Last Level Cache
Controller (LLCC) and in downstream sources is called BWMON v4 (or v4 of
register layout).

SDM845 also has also BWMON instance measuring traffic between LLCC and
memory with different register layout: called v5.

Add support for this "LLCC" BWMON. Differences against existing v4 one:
1. No global interrupts.
2. Different register layout.
3. Different shift of interrupt fields.
4. Smaller sampling window.

Cc: Rajendra Nayak <quic_rjendra@quicinc.com>
Cc: Sibi Sankar <quic_sibis@quicinc.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Tested-by: Steev Klimaszewski <steev@kali.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220728113748.170548-10-krzysztof.kozlowski@linaro.org

soc: qcom: icc-bwmon: add per-variant quirks

BWMON v5 lacks global interrupt registers. Other BWMON versions differ
as well, so add quirks for easier customization of code flow.

Cc: Rajendra Nayak <quic_rjendra@quicinc.com>
Cc: Sibi Sankar <quic_sibis@quicinc.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Tested-by: Steev Klimaszewski <steev@kali.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220728113748.170548-9-krzysztof.kozlowski@linaro.org

soc: qcom: icc-bwmon: use regmap and prepare for BWMON v5

Refactor the code to prepare it for supporting BWMON v5 which comes with
different register layout by:
1. Adding use of MMIO regmap and regmap fields which allows to keep one
code logic with different register maps.
2. The "clear" type registers do not allow reading, therefore regmap
requires using cache with default values.
3. regmap has an effect of introducing barriers after each readl/writel,
which should negligible effect as only few writes were relaxed.
4. Additionally usage of regmap fields removes need of shifting the
register values.
5. Add "V4" prefix to names of all defines with register addresses (so
BWMON_V4_xxx) to differentiate it from V5. The actual register values
are shared so keep their naming.
6. While changing the defines, pad register addresses to three digits
for readability.

Cc: Rajendra Nayak <quic_rjendra@quicinc.com>
Cc: Sibi Sankar <quic_sibis@quicinc.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Tested-by: Steev Klimaszewski <steev@kali.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220728113748.170548-8-krzysztof.kozlowski@linaro.org

soc: qcom: icc-bwmon: store count unit per variant

Versions v4 and v5 of BWMON on SDM845 use different unit count, so allow
easier variant customization by storing its value in struct
icc_bwmon_data.

Cc: Rajendra Nayak <quic_rjendra@quicinc.com>
Cc: Sibi Sankar <quic_sibis@quicinc.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Sibi Sankar <quic_sibis@quicinc.com>
Tested-by: Steev Klimaszewski <steev@kali.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220728113748.170548-7-krzysztof.kozlowski@linaro.org

soc: qcom: icc-bwmon: clear all registers on init

The hardware programming guide recommends to clear all registers on
first initialization, through separate field in BWMON_CLEAR register.

This makes sense in general but especially if driver is rebound to avoid
spurious/early interrupts.

Cc: Rajendra Nayak <quic_rjendra@quicinc.com>
Cc: Sibi Sankar <quic_sibis@quicinc.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Tested-by: Steev Klimaszewski <steev@kali.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220728113748.170548-6-krzysztof.kozlowski@linaro.org

soc: qcom: icc-bwmon: store reference to variant data in container

Instead of copying pieces of variant-specific data (struct
icc_bwmon_data) into the state container (struct icc_bwmon), just store
a pointer to it.

This simplifies a bit the code and allows later to grow easily the
variant-specific data for new BWMON v5.

Cc: Rajendra Nayak <quic_rjendra@quicinc.com>
Cc: Sibi Sankar <quic_sibis@quicinc.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Sibi Sankar <quic_sibis@quicinc.com>
Tested-by: Steev Klimaszewski <steev@kali.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220728113748.170548-5-krzysztof.kozlowski@linaro.org

soc: qcom: icc-bwmon: drop unused registers

BWMON_GLOBAL_IRQ_STATUS and BWMON_ZONE_COUNT defines are not used.

Cc: Rajendra Nayak <quic_rjendra@quicinc.com>
Cc: Sibi Sankar <quic_sibis@quicinc.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Sibi Sankar <quic_sibis@quicinc.com>
Tested-by: Steev Klimaszewski <steev@kali.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220728113748.170548-4-krzysztof.kozlowski@linaro.org

soc: qcom: icc-bwmon: re-use IRQ enable/clear define

The interrupt enable, status and clear registers have the same layout,
so BWMON_GLOBAL_IRQ_ENABLE_ENABLE define can be used also for clearing
IRQ, instead of hard-coded value.

Cc: Rajendra Nayak <quic_rjendra@quicinc.com>
Cc: Sibi Sankar <quic_sibis@quicinc.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Sibi Sankar <quic_sibis@quicinc.com>
Tested-by: Steev Klimaszewski <steev@kali.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220728113748.170548-3-krzysztof.kozlowski@linaro.org

soc: qcom: icc-bwmon: Remove unnecessary print function dev_err()

Eliminate the follow coccicheck warning:
./drivers/soc/qcom/icc-bwmon.c:349:2-9: line 349 is redundant because platform_get_irq() already prints an error

Fixes: b9c2ae6cac40 ("soc: qcom: icc-bwmon: Add bandwidth monitoring driver")
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220714075532.104665-1-yang.lee@linux.alibaba.com

soc: qcom: icc-bwmon: Add bandwidth monitoring driver

Bandwidth monitoring (BWMON) sits between various subsytems like CPU,
GPU, Last Level caches and memory subsystem. The BWMON can be
configured to monitor the data throuhput between memory and other
subsytems. The throughput is measured within specified sampling window
and is used to vote for corresponding interconnect bandwidth.

Current implementation brings support for BWMON v4, used for example on
SDM845 to measure bandwidth between CPU (gladiator_noc) and Last Level
Cache (memnoc). Usage of this BWMON allows to remove fixed bandwidth
votes from cpufreq (CPU nodes) thus achieve high memory throughput even
with lower CPU frequencies.

The driver was tested on SDM845.

Co-developed-by: Thara Gopinath <thara.gopinath@gmail.com>
Signed-off-by: Thara Gopinath <thara.gopinath@gmail.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220704121730.127925-3-krzysztof.kozlowski@linaro.org