[Nouveau] [PATCH 3/9] pci: implement generic code for PCIe speed change

Roy Spliet
2015-10-12T21:13:46Z

Some more minor nitting!

Op 12-10-15 om 21:27 schreef Karol Herbst:
> Signed-off-by: Karol Herbst <nouveau at karolherbst.de>
> ---
>   drm/nouveau/include/nvkm/subdev/pci.h |  12 +++
>   drm/nouveau/nvkm/subdev/pci/Kbuild    |   1 +
>   drm/nouveau/nvkm/subdev/pci/base.c    |   5 ++
>   drm/nouveau/nvkm/subdev/pci/pcie.c    | 159
++++++++++++++++++++++++++++++++++
>   drm/nouveau/nvkm/subdev/pci/priv.h    |  12 +++
>   5 files changed, 189 insertions(+)
>   create mode 100644 drm/nouveau/nvkm/subdev/pci/pcie.c
>
> diff --git a/drm/nouveau/include/nvkm/subdev/pci.h
b/drm/nouveau/include/nvkm/subdev/pci.h
> index 17fe7b7..e195736 100644
> --- a/drm/nouveau/include/nvkm/subdev/pci.h
> +++ b/drm/nouveau/include/nvkm/subdev/pci.h
> @@ -2,6 +2,12 @@
>   #define __NVKM_PCI_H__
>   #include <core/subdev.h>
>
> +enum nvkm_pcie_speed {
> +	NVKM_PCIE_SPEED_2_5,
> +	NVKM_PCIE_SPEED_5_0,
> +	NVKM_PCIE_SPEED_8_0,
> +};
> +
>   struct nvkm_pci {
>   	const struct nvkm_pci_func *func;
>   	struct nvkm_subdev subdev;
> @@ -18,6 +24,11 @@ struct nvkm_pci {
>   		bool acquired;
>   	} agp;
>
> +	struct {
> +		enum nvkm_pcie_speed last_speed;
> +		u8 last_width;
> +	} pcie;
> +
>   	bool msi;
>   };
>
> @@ -26,6 +37,7 @@ void nvkm_pci_wr08(struct nvkm_pci *, u16 addr, u8 data);
>   void nvkm_pci_wr32(struct nvkm_pci *, u16 addr, u32 data);
>   u32 nvkm_pci_mask(struct nvkm_pci *, u16 addr, u32 mask, u32 value);
>   void nvkm_pci_rom_shadow(struct nvkm_pci *, bool shadow);
> +int nvkm_pci_set_pcie_link(struct nvkm_pci *, enum nvkm_pcie_speed, u8
width);
>
>   int nv04_pci_new(struct nvkm_device *, int, struct nvkm_pci **);
>   int nv40_pci_new(struct nvkm_device *, int, struct nvkm_pci **);
> diff --git a/drm/nouveau/nvkm/subdev/pci/Kbuild
b/drm/nouveau/nvkm/subdev/pci/Kbuild
> index 724afd4..3c2519f 100644
> --- a/drm/nouveau/nvkm/subdev/pci/Kbuild
> +++ b/drm/nouveau/nvkm/subdev/pci/Kbuild
> @@ -1,5 +1,6 @@
>   nvkm-y += nvkm/subdev/pci/agp.o
>   nvkm-y += nvkm/subdev/pci/base.o
> +nvkm-y += nvkm/subdev/pci/pcie.o
>   nvkm-y += nvkm/subdev/pci/nv04.o
>   nvkm-y += nvkm/subdev/pci/nv40.o
>   nvkm-y += nvkm/subdev/pci/nv46.o
> diff --git a/drm/nouveau/nvkm/subdev/pci/base.c
b/drm/nouveau/nvkm/subdev/pci/base.c
> index d671dcf..3895ab2 100644
> --- a/drm/nouveau/nvkm/subdev/pci/base.c
> +++ b/drm/nouveau/nvkm/subdev/pci/base.c
> @@ -117,6 +117,9 @@ nvkm_pci_init(struct nvkm_subdev *subdev)
>   		ret = nvkm_agp_init(pci);
>   		if (ret)
>   			return ret;
> +	} else {
> +		if (pci_is_pcie(pci->pdev))
> +			nvkm_pci_pcie_init(pci);
>   	}
>
>   	if (pci->func->init)
> @@ -160,6 +163,8 @@ nvkm_pci_new_(const struct nvkm_pci_func *func, struct
nvkm_device *device,
>   	pci->func = func;
>   	pci->pdev = device->func->pci(device)->pdev;
>   	pci->irq = -1;
> +	pci->pcie.last_speed = -1;
> +	pci->pcie.last_width = -1;
>
>   	if (device->type == NVKM_DEVICE_AGP)
>   		nvkm_agp_ctor(pci);
> diff --git a/drm/nouveau/nvkm/subdev/pci/pcie.c
b/drm/nouveau/nvkm/subdev/pci/pcie.c
> new file mode 100644
> index 0000000..05e9c55
> --- /dev/null
> +++ b/drm/nouveau/nvkm/subdev/pci/pcie.c
> @@ -0,0 +1,159 @@
> +/*
> + * Copyright 2015 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 <git at karolherbst.de>
> + */
> +#include "priv.h"
> +
> +static char *pcie_speed_strings[] = {
> +	"2.5GT/s",
> +	"5.0GT/s",
> +	"8.0GT/s",
> +};
> +
> +static enum nvkm_pcie_speed
> +pci_bus_speed_to_nvkm_pcie_speed(enum pci_bus_speed speed)
> +{
> +	switch (speed) {
> +	case PCIE_SPEED_2_5GT:
> +		return NVKM_PCIE_SPEED_2_5;
> +	case PCIE_SPEED_5_0GT:
> +		return NVKM_PCIE_SPEED_5_0;
> +	case PCIE_SPEED_8_0GT:
> +		return NVKM_PCIE_SPEED_8_0;
> +	default:
> +		if (speed == 0x17) // 0x16 is 8_0, assume 0x17 will be 16_0 for now
Please stick to C-style /* blah */ comments. This particular could
warrant an "XXX" label to indicate it's a
todo.
> +			return NVKM_PCIE_SPEED_8_0;
> +		return -1;
> +	}
> +}
> +
> +static s8
> +nvkm_pci_get_pcie_version(struct nvkm_pci *pci)
> +{
> +	if (!pci_is_pcie(pci->pdev))
> +		return -ENODEV;
> +
> +	if (!pci->func->get_pcie_version)
> +		return -ENOSYS;
> +
> +	return pci->func->get_pcie_version(pci);
> +}
> +
> +static s8
> +nvkm_pci_raise_pcie_version(struct nvkm_pci *pci)
> +{
> +	int ret, supported;
> +
> +	if (!pci_is_pcie(pci->pdev))
> +		return -ENODEV;
> +
> +	if (!pci->func->set_pcie_version ||
!pci->func->get_pcie_version_supported)
> +		return -ENOSYS;
> +
> +	ret = nvkm_pci_get_pcie_version(pci);
> +	supported = pci->func->get_pcie_version_supported(pci);
> +	if (ret == 1 && ret < supported) {
> +		nvkm_debug(&pci->subdev, "raising version\n");
> +		pci->func->set_pcie_version(pci, supported);
> +		ret = nvkm_pci_get_pcie_version(pci);
> +	}
> +	return ret >= supported ? ret : -EINVAL;
> +}
> +
> +int
> +nvkm_pci_pcie_init(struct nvkm_pci *pci)
> +{
> +	struct nvkm_subdev *subdev = &pci->subdev;
> +	int ret;
> +
> +	if (!pci_is_pcie(pci->pdev))
> +		return -ENODEV;
> +
> +	// raise pcie version first
Ditto.
> +	ret = nvkm_pci_raise_pcie_version(pci);
> +	if (ret <= 0)
> +		nvkm_error(subdev, "couldn't raise version: %i\n", ret);
> +
> +	if (pci->func->pcie_speed_init)
> +		pci->func->pcie_speed_init(pci);
> +
> +	nvkm_info(subdev, "pcie version: %i\n",
nvkm_pci_get_pcie_version(pci));
> +	if (pci->func->pcie_max_speed)
> +		nvkm_info(subdev, "pcie max speed: %s\n",
pcie_speed_strings[pci->func->pcie_max_speed(pci)]);
> +
> +	if (pci->pcie.last_speed != -1)
> +		nvkm_pci_set_pcie_link(pci, pci->pcie.last_speed,
pci->pcie.last_width);
> +
> +	return 0;
> +}
> +
> +int
> +nvkm_pci_set_pcie_link(struct nvkm_pci * pci, enum nvkm_pcie_speed
req_speed, u8 req_width)
> +{
> +	struct nvkm_subdev *subdev = &pci->subdev;
> +	enum nvkm_pcie_speed sys_cur_speed, sys_max_speed;
> +	struct pci_bus *pbus = pci->pdev->bus;
> +	int ret;
> +
> +	if (!pci_is_pcie(pci->pdev))
> +		return -ENODEV;
> +
> +	if (!pci->func->pcie_speed_set ||
!pci->func->get_pcie_version || !pci->func->pcie_max_speed ||
!pci->func->pcie_current_speed)
> +		return -ENOSYS;
> +
> +	nvkm_debug(subdev, "pcie speed %s requested\n",
pcie_speed_strings[req_speed]);
> +
> +	if (pci->func->get_pcie_version(pci) < 2) {
> +		nvkm_error(subdev, "can't change link speed, "
> +				"because current version too low\n");
> +		return -ENODEV;
> +	}
> +
> +	sys_cur_speed = pci->func->pcie_current_speed(pci);
> +	sys_max_speed =
min(pci_bus_speed_to_nvkm_pcie_speed(pbus->max_bus_speed),
pci->func->pcie_max_speed(pci));
> +
> +	nvkm_debug(subdev, "bus current speed: %s max speed: %s\n",
> +			pcie_speed_strings[sys_cur_speed], pcie_speed_strings[sys_max_speed]);
> +
> +	if (req_speed > sys_max_speed) {
> +		req_speed = sys_max_speed;
> +		nvkm_warn(subdev, "bus or card not fast enough, dropping "
> +				"requested speed to %s", pcie_speed_strings[req_speed]);
> +	}
> +
> +	pci->pcie.last_speed = req_speed;
> +	pci->pcie.last_width = req_width;
> +
> +	if (req_speed == sys_cur_speed) {
> +		nvkm_debug(subdev, "requested speed matches current speed
already\n");
> +		return req_speed;
> +	}
> +
> +	nvkm_debug(subdev, "set link to speed: %s width: x%i\n",
> +			pcie_speed_strings[req_speed], req_width);
> +	ret = pci->func->pcie_speed_set(pci, req_speed, req_width);
> +
> +	if (ret < 0)
> +		nvkm_error(subdev, "setting link failed with ret: %i\n", ret);
> +
> +	return ret;
> +}
> diff --git a/drm/nouveau/nvkm/subdev/pci/priv.h
b/drm/nouveau/nvkm/subdev/pci/priv.h
> index cf46d38..11c266f 100644
> --- a/drm/nouveau/nvkm/subdev/pci/priv.h
> +++ b/drm/nouveau/nvkm/subdev/pci/priv.h
> @@ -12,6 +12,16 @@ struct nvkm_pci_func {
>   	void (*wr08)(struct nvkm_pci *, u16 addr, u8 data);
>   	void (*wr32)(struct nvkm_pci *, u16 addr, u32 data);
>   	void (*msi_rearm)(struct nvkm_pci *);
> +
> +	int (*pcie_speed_init)(struct nvkm_pci *);
> +	int (*pcie_speed_set)(struct nvkm_pci *, enum nvkm_pcie_speed, u8);
> +
> +	enum nvkm_pcie_speed (*pcie_max_speed)(struct nvkm_pci *);
> +	enum nvkm_pcie_speed (*pcie_current_speed)(struct nvkm_pci *);
> +
> +	void (*set_pcie_version)(struct nvkm_pci *, u8);
> +	u8 (*get_pcie_version)(struct nvkm_pci *);
> +	u8 (*get_pcie_version_supported)(struct nvkm_pci *);
>   };
>
>   u32 nv40_pci_rd32(struct nvkm_pci *, u16);
> @@ -22,4 +32,6 @@ void nv40_pci_msi_rearm(struct nvkm_pci *);
>   void nv46_pci_msi_rearm(struct nvkm_pci *);
>
>   void g84_pci_init(struct nvkm_pci *pci);
> +
> +int nvkm_pci_pcie_init(struct nvkm_pci *pci);
>   #endif