[Nouveau] [PATCH v4 10/37] add daemon to compare nouveau with blob voltage

[Martin Peres]

On 18/04/16 22:13, Karol Herbst wrote:
> this tool can be run alongside the nvidia driver to print information about
> the current p/cstate, which voltage was set by nvidia and what nouveau would
> set in the same situation.
>
> v4: parse default options
>
> Signed-off-by: Karol Herbst <nouveau at karolherbst.de>
> ---
>   bin/nv_cmp_volt.c | 139 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 139 insertions(+)
>   create mode 100644 bin/nv_cmp_volt.c
>
> diff --git a/bin/nv_cmp_volt.c b/bin/nv_cmp_volt.c
> new file mode 100644
> index 0000000..c63d91b
> --- /dev/null
> +++ b/bin/nv_cmp_volt.c
> @@ -0,0 +1,139 @@
> +/*
> + * Copyright 2016 Karol Herbst
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice shall be included in
> + * all copies or substantial portions of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
> + * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
> + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
> + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
> + * OTHER DEALINGS IN THE SOFTWARE.
> + *
> + * Authors: Karol Herbst
> + */
> +
> +#include <nvif/client.h>
> +#include <nvif/device.h>
> +#include <nvif/class.h>
> +
> +#include <nvkm/subdev/volt.h>
> +
> +#include "util.h"
> +
> +int
> +main(int argc, char **argv)
> +{
> +	struct nvif_client if_client;
> +	struct nvif_device if_device;
> +	struct nvkm_clk *clk;
> +	struct nvkm_volt *volt;
> +	struct nvkm_device *device;
> +	int ret, c;
> +	int old_voltage = 0, old_nouveau_voltage = 0, old_pstate = 0;
> +	int old_cstate = 0, old_temp = 0;
> +
> +	while ((c = getopt(argc, argv, U_GETOPT)) != -1) {
> +		switch (c) {
> +		default:
> +			if (!u_option(c))
> +				return 1;
> +			break;
> +		}
> +	}
> +
> +	ret = u_device("lib", argv[0], "error", true, true,
> +                       (1ULL << NVKM_SUBDEV_CLK) |
> +//                       (1ULL << NVKM_SUBDEV_FUSE) |
> +                       (1ULL << NVKM_SUBDEV_GPIO) |
> +//                       (1ULL << NVKM_SUBDEV_I2C) |
> +                       (1ULL << NVKM_SUBDEV_PCI) |
> +//                       (1ULL << NVKM_SUBDEV_THERM) |
> +//                       (1ULL << NVKM_SUBDEV_TIMER) |
// is not a C thing, it is only in c++. Please use /* */

Now, this is also a good place to say why ptherm is problematic for you 
and how you will just read the reg instead.

> +                       (1ULL << NVKM_SUBDEV_VBIOS) |
> +                       (1ULL << NVKM_SUBDEV_VOLT),
> +                       0x00000000, &if_client, &if_device);
> +
> +	if (ret < 0)
> +		return ret;
> +
> +	device = nvxx_device(&if_device);
> +	clk = device->clk;
> +//	therm = device->therm;

I would say get rid of this commented code.

> +	volt = device->volt;
> +
> +	printf("current voltage (µV), expected voltage (µV), abs diff (µV),"
> +	       "rel diff nouveau/nvidia (%%), pstate, cstate, temperature"
> +	       "(°C)\n");
> +	while (true) {
> +		int gpc_clock = nvkm_clk_read(clk, nv_clk_src_gpc);
> +		int mem_clock = nvkm_clk_read(clk, nv_clk_src_mem);
> +		struct nvkm_pstate *pstate = NULL, *best_pstate = NULL;
> +		struct nvkm_cstate *cstate = NULL, *best_cstate = NULL;
> +		int mem_err, gpc_err;
> +		int new_voltage, new_nouveau_voltage, new_pstate, new_cstate;
> +		int new_temp;
> +

/* try to map the clocks set by NVIDIA to the closest pstate/cstate */

> +		list_for_each_entry(pstate, &clk->states, head) {
> +			list_for_each_entry(cstate, &pstate->list, head) {
> +				if (!best_pstate) {
> +					best_pstate = pstate;
> +					best_cstate = cstate;
> +					gpc_err = abs(cstate->domain[nv_clk_src_gpc] - gpc_clock);
> +					mem_err = abs(cstate->domain[nv_clk_src_mem] - mem_clock);
> +					continue;
> +				}
> +
> +				if (abs(cstate->domain[nv_clk_src_gpc] - gpc_clock) <= gpc_err &&
> +				    abs(cstate->domain[nv_clk_src_mem] - mem_clock) <= mem_err) {
> +					best_pstate = pstate;
> +					best_cstate = cstate;
> +					gpc_err = abs(cstate->domain[nv_clk_src_gpc] - gpc_clock);
> +					mem_err = abs(cstate->domain[nv_clk_src_mem] - mem_clock);
> +				}
> +			}
> +
> +			if (!best_pstate) {
> +				best_pstate = pstate;
> +				mem_err = abs(cstate->domain[nv_clk_src_mem] - mem_clock);
> +				continue;
> +			} else if (!best_cstate && abs(pstate->base.domain[nv_clk_src_mem] - mem_clock) <= mem_err) {
> +				best_pstate = pstate;
> +				mem_err = abs(cstate->domain[nv_clk_src_mem] - mem_clock);
> +			}
> +		}
> +
> +		if (!best_cstate)
> +			best_cstate = &best_pstate->base;
> +
> +		new_voltage = nvkm_volt_get(volt);
> +		new_temp = nvkm_rd32(device, 0x20400);//nvkm_therm_temp_get(therm);

Same here, get rid of the comment.

> +		new_nouveau_voltage = max(nvkm_volt_map(volt, best_cstate->voltage), nvkm_volt_map(volt, best_pstate->base.voltage));
> +		new_pstate = best_pstate->pstate;
> +		new_cstate = best_cstate->cstate;
> +
> +		if (new_voltage != old_voltage || new_nouveau_voltage != old_nouveau_voltage || new_pstate != old_pstate || new_cstate != old_cstate || new_temp != old_temp) {
> +			old_voltage = new_voltage;
> +			old_nouveau_voltage = new_nouveau_voltage;
> +			old_pstate = new_pstate;
> +			old_cstate = new_cstate;
> +			old_temp = new_temp;
> +			printf("%i, %i, %i, %f, %i, %i, %i\n", new_voltage,
> +			       new_nouveau_voltage, new_nouveau_voltage - new_voltage,
> +			       100 * (double)new_nouveau_voltage / new_voltage,
> +			       new_pstate, new_cstate, new_temp);
> +		}
> +		usleep(100000);
> +	}
> +
> +	return 0;
> +}

I am surprised by how short this tool is. This is great! With the 
nitpicks addressed, this is :

Reviewed-by: Martin Peres <martin.peres at free.fr>