diff mbox series

[v5,1/3] PCI: qcom: Refactor common code

Message ID 20240821170917.21018-2-quic_schintav@quicinc.com (mailing list archive)
State Superseded
Delegated to: Manivannan Sadhasivam
Headers show
Series pci: qcom: Add 16GT/s equalization and margining settings | expand

Commit Message

Shashank Babu Chinta Venkata Aug. 21, 2024, 5:08 p.m. UTC
Refactor common code from RC(Root Complex) and EP(End Point)
drivers and move them to a common driver. This acts as placeholder
for common source code for both drivers, thus avoiding duplication.

Signed-off-by: Shashank Babu Chinta Venkata <quic_schintav@quicinc.com>
---
 MAINTAINERS                                   |   3 +
 drivers/pci/controller/dwc/Kconfig            |   5 +
 drivers/pci/controller/dwc/Makefile           |   1 +
 drivers/pci/controller/dwc/pcie-qcom-common.c |  88 +++++++++++
 drivers/pci/controller/dwc/pcie-qcom-common.h |  15 ++
 drivers/pci/controller/dwc/pcie-qcom-ep.c     |  39 +----
 drivers/pci/controller/dwc/pcie-qcom.c        | 141 ++++++------------
 7 files changed, 161 insertions(+), 131 deletions(-)
 create mode 100644 drivers/pci/controller/dwc/pcie-qcom-common.c
 create mode 100644 drivers/pci/controller/dwc/pcie-qcom-common.h

Comments

Bjorn Helgaas Aug. 21, 2024, 5:33 p.m. UTC | #1
On Wed, Aug 21, 2024 at 10:08:42AM -0700, Shashank Babu Chinta Venkata wrote:
> Refactor common code from RC(Root Complex) and EP(End Point)
> drivers and move them to a common driver. This acts as placeholder
> for common source code for both drivers, thus avoiding duplication.

Much of this seems to be replacing qcom_pcie_icc_opp_update() and
qcom_pcie_ep_icc_update() with qcom_pcie_common_icc_update().

That seems worthwhile and it would be helpful if the commit log called
that out so we'd know what to look for in the patch.

I think the qcom_pcie_common_icc_init() rework would be more
understandable if it were in its own patch and not mixed in here.

> +++ b/drivers/pci/controller/dwc/pcie-qcom-common.c
> @@ -0,0 +1,88 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2014-2015, 2020 The Linux Foundation. All rights reserved.
> + * Copyright (c) 2015, 2021 Linaro Limited.
> + * Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved.
> + *

Spurious blank line.

> + */

> +struct icc_path *qcom_pcie_common_icc_get_resource(struct dw_pcie *pci, const char *path)
> +{
> +	struct icc_path *icc_p;
> +
> +	icc_p = devm_of_icc_get(pci->dev, path);
> +	return icc_p;

  return devm_of_icc_get(pci->dev, path);

> +}
> +EXPORT_SYMBOL_GPL(qcom_pcie_common_icc_get_resource);
> +
> +int qcom_pcie_common_icc_init(struct dw_pcie *pci, struct icc_path *icc, u32 bandwidth)
> +{
> +	int ret;
> +
> +	ret = icc_set_bw(icc, 0, bandwidth);
> +	if (ret) {
> +		dev_err(pci->dev, "Failed to set interconnect bandwidth: %d\n",
> +			ret);
> +		return ret;
> +	}

The callers also check and log similar messages.  I don't see the
point.

> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(qcom_pcie_common_icc_init);

These both seem of dubious value.

> +++ b/drivers/pci/controller/dwc/pcie-qcom-common.h

Do we need "-common" in the filename?  Seems like "pcie-qcom.h" would
be enough.  I *hope* we don't someday need both a "pcie-qcom.h and a
"pcie-qcom-common.h"; that seems like it would really be overkill.

Bjorn
kernel test robot Aug. 24, 2024, 4:15 p.m. UTC | #2
Hi Shashank,

kernel test robot noticed the following build errors:

[auto build test ERROR on pci/next]
[also build test ERROR on linus/master v6.11-rc4]
[cannot apply to pci/for-linus next-20240823]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Shashank-Babu-Chinta-Venkata/PCI-qcom-Refactor-common-code/20240822-011229
base:   https://git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git next
patch link:    https://lore.kernel.org/r/20240821170917.21018-2-quic_schintav%40quicinc.com
patch subject: [PATCH v5 1/3] PCI: qcom: Refactor common code
config: x86_64-allyesconfig (https://download.01.org/0day-ci/archive/20240824/202408242300.2ECtncwN-lkp@intel.com/config)
compiler: clang version 18.1.5 (https://github.com/llvm/llvm-project 617a15a9eac96088ae5e9134248d8236e34b91b1)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240824/202408242300.2ECtncwN-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202408242300.2ECtncwN-lkp@intel.com/

All errors (new ones prefixed by >>):

>> drivers/pci/controller/dwc/pcie-qcom-ep.c:321:55: error: too few arguments to function call, expected 3, have 2
     321 |         ret = qcom_pcie_common_icc_init(pci, pcie_ep->icc_mem);
         |               ~~~~~~~~~~~~~~~~~~~~~~~~~                      ^
   drivers/pci/controller/dwc/pcie-qcom-common.h:14:5: note: 'qcom_pcie_common_icc_init' declared here
      14 | int qcom_pcie_common_icc_init(struct dw_pcie *pci, struct icc_path *icc_mem, u32 bandwidth);
         |     ^                         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   1 error generated.


vim +321 drivers/pci/controller/dwc/pcie-qcom-ep.c

   295	
   296	static int qcom_pcie_enable_resources(struct qcom_pcie_ep *pcie_ep)
   297	{
   298		struct dw_pcie *pci = &pcie_ep->pci;
   299		int ret;
   300	
   301		ret = clk_bulk_prepare_enable(pcie_ep->num_clks, pcie_ep->clks);
   302		if (ret)
   303			return ret;
   304	
   305		ret = qcom_pcie_ep_core_reset(pcie_ep);
   306		if (ret)
   307			goto err_disable_clk;
   308	
   309		ret = phy_init(pcie_ep->phy);
   310		if (ret)
   311			goto err_disable_clk;
   312	
   313		ret = phy_set_mode_ext(pcie_ep->phy, PHY_MODE_PCIE, PHY_MODE_PCIE_EP);
   314		if (ret)
   315			goto err_phy_exit;
   316	
   317		ret = phy_power_on(pcie_ep->phy);
   318		if (ret)
   319			goto err_phy_exit;
   320	
 > 321		ret = qcom_pcie_common_icc_init(pci, pcie_ep->icc_mem);
   322		if (ret) {
   323			dev_err(pci->dev, "failed to set interconnect bandwidth: %d\n",
   324				ret);
   325			goto err_phy_off;
   326		}
   327	
   328		return 0;
   329	
   330	err_phy_off:
   331		phy_power_off(pcie_ep->phy);
   332	err_phy_exit:
   333		phy_exit(pcie_ep->phy);
   334	err_disable_clk:
   335		clk_bulk_disable_unprepare(pcie_ep->num_clks, pcie_ep->clks);
   336	
   337		return ret;
   338	}
   339
kernel test robot Aug. 24, 2024, 6:06 p.m. UTC | #3
Hi Shashank,

kernel test robot noticed the following build errors:

[auto build test ERROR on pci/next]
[also build test ERROR on linus/master v6.11-rc4]
[cannot apply to pci/for-linus next-20240823]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Shashank-Babu-Chinta-Venkata/PCI-qcom-Refactor-common-code/20240822-011229
base:   https://git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git next
patch link:    https://lore.kernel.org/r/20240821170917.21018-2-quic_schintav%40quicinc.com
patch subject: [PATCH v5 1/3] PCI: qcom: Refactor common code
config: i386-allmodconfig (https://download.01.org/0day-ci/archive/20240824/202408242341.lywV11DL-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240824/202408242341.lywV11DL-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202408242341.lywV11DL-lkp@intel.com/

All errors (new ones prefixed by >>):

   drivers/pci/controller/dwc/pcie-qcom-ep.c: In function 'qcom_pcie_enable_resources':
>> drivers/pci/controller/dwc/pcie-qcom-ep.c:321:15: error: too few arguments to function 'qcom_pcie_common_icc_init'
     321 |         ret = qcom_pcie_common_icc_init(pci, pcie_ep->icc_mem);
         |               ^~~~~~~~~~~~~~~~~~~~~~~~~
   In file included from drivers/pci/controller/dwc/pcie-qcom-ep.c:28:
   drivers/pci/controller/dwc/pcie-qcom-common.h:14:5: note: declared here
      14 | int qcom_pcie_common_icc_init(struct dw_pcie *pci, struct icc_path *icc_mem, u32 bandwidth);
         |     ^~~~~~~~~~~~~~~~~~~~~~~~~


vim +/qcom_pcie_common_icc_init +321 drivers/pci/controller/dwc/pcie-qcom-ep.c

   295	
   296	static int qcom_pcie_enable_resources(struct qcom_pcie_ep *pcie_ep)
   297	{
   298		struct dw_pcie *pci = &pcie_ep->pci;
   299		int ret;
   300	
   301		ret = clk_bulk_prepare_enable(pcie_ep->num_clks, pcie_ep->clks);
   302		if (ret)
   303			return ret;
   304	
   305		ret = qcom_pcie_ep_core_reset(pcie_ep);
   306		if (ret)
   307			goto err_disable_clk;
   308	
   309		ret = phy_init(pcie_ep->phy);
   310		if (ret)
   311			goto err_disable_clk;
   312	
   313		ret = phy_set_mode_ext(pcie_ep->phy, PHY_MODE_PCIE, PHY_MODE_PCIE_EP);
   314		if (ret)
   315			goto err_phy_exit;
   316	
   317		ret = phy_power_on(pcie_ep->phy);
   318		if (ret)
   319			goto err_phy_exit;
   320	
 > 321		ret = qcom_pcie_common_icc_init(pci, pcie_ep->icc_mem);
   322		if (ret) {
   323			dev_err(pci->dev, "failed to set interconnect bandwidth: %d\n",
   324				ret);
   325			goto err_phy_off;
   326		}
   327	
   328		return 0;
   329	
   330	err_phy_off:
   331		phy_power_off(pcie_ep->phy);
   332	err_phy_exit:
   333		phy_exit(pcie_ep->phy);
   334	err_disable_clk:
   335		clk_bulk_disable_unprepare(pcie_ep->num_clks, pcie_ep->clks);
   336	
   337		return ret;
   338	}
   339
Manivannan Sadhasivam Aug. 25, 2024, 6:06 a.m. UTC | #4
On Wed, Aug 21, 2024 at 10:08:42AM -0700, Shashank Babu Chinta Venkata wrote:
> Refactor common code from RC(Root Complex) and EP(End Point)
> drivers and move them to a common driver. This acts as placeholder
> for common source code for both drivers, thus avoiding duplication.
> 
> Signed-off-by: Shashank Babu Chinta Venkata <quic_schintav@quicinc.com>
> ---
>  MAINTAINERS                                   |   3 +
>  drivers/pci/controller/dwc/Kconfig            |   5 +
>  drivers/pci/controller/dwc/Makefile           |   1 +
>  drivers/pci/controller/dwc/pcie-qcom-common.c |  88 +++++++++++
>  drivers/pci/controller/dwc/pcie-qcom-common.h |  15 ++
>  drivers/pci/controller/dwc/pcie-qcom-ep.c     |  39 +----
>  drivers/pci/controller/dwc/pcie-qcom.c        | 141 ++++++------------
>  7 files changed, 161 insertions(+), 131 deletions(-)
>  create mode 100644 drivers/pci/controller/dwc/pcie-qcom-common.c
>  create mode 100644 drivers/pci/controller/dwc/pcie-qcom-common.h
> 

[...]

> diff --git a/drivers/pci/controller/dwc/pcie-qcom-common.c b/drivers/pci/controller/dwc/pcie-qcom-common.c
> new file mode 100644
> index 000000000000..1d8992147bba
> --- /dev/null
> +++ b/drivers/pci/controller/dwc/pcie-qcom-common.c
> @@ -0,0 +1,88 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2014-2015, 2020 The Linux Foundation. All rights reserved.
> + * Copyright (c) 2015, 2021 Linaro Limited.
> + * Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved.
> + *
> + */
> +
> +#include <linux/pci.h>
> +#include <linux/interconnect.h>
> +#include <linux/pm_opp.h>
> +#include <linux/units.h>
> +
> +#include "../../pci.h"
> +#include "pcie-designware.h"
> +#include "pcie-qcom-common.h"
> +
> +struct icc_path *qcom_pcie_common_icc_get_resource(struct dw_pcie *pci, const char *path)

On top of Bjorn's review:

I think you can just use qcom_pcie_common_icc_get() as _resource suffix is not
really needed.

> +{
> +	struct icc_path *icc_p;
> +
> +	icc_p = devm_of_icc_get(pci->dev, path);
> +	return icc_p;
> +}
> +EXPORT_SYMBOL_GPL(qcom_pcie_common_icc_get_resource);
> +
> +int qcom_pcie_common_icc_init(struct dw_pcie *pci, struct icc_path *icc, u32 bandwidth)
> +{
> +	int ret;
> +
> +	ret = icc_set_bw(icc, 0, bandwidth);
> +	if (ret) {
> +		dev_err(pci->dev, "Failed to set interconnect bandwidth: %d\n",
> +			ret);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(qcom_pcie_common_icc_init);
> +
> +void qcom_pcie_common_icc_update(struct dw_pcie *pci, struct icc_path *icc_mem)
> +{
> +	u32 offset, status, width, speed;
> +	unsigned long freq_kbps;
> +	struct dev_pm_opp *opp;
> +	int ret, freq_mbps;
> +
> +	if (!icc_mem)
> +		return;

With this check in place, below OPP code will never get executed.

> +
> +	offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
> +	status = readw(pci->dbi_base + offset + PCI_EXP_LNKSTA);
> +
> +	/* Only update constraints if link is up. */
> +	if (!(status & PCI_EXP_LNKSTA_DLLLA))
> +		return;
> +
> +	speed = FIELD_GET(PCI_EXP_LNKSTA_CLS, status);
> +	width = FIELD_GET(PCI_EXP_LNKSTA_NLW, status);
> +
> +	if (icc_mem) {
> +		ret = icc_set_bw(icc_mem, 0,
> +				 width * QCOM_PCIE_LINK_SPEED_TO_BW(speed));
> +		if (ret) {
> +			dev_err(pci->dev, "Failed to set bandwidth for PCIe-MEM interconnect path: %d\n",
> +				ret);
> +		}
> +	} else {
> +		freq_mbps = pcie_dev_speed_mbps(pcie_link_speed[speed]);
> +		if (freq_mbps < 0)
> +			return;
> +
> +		freq_kbps = freq_mbps * KILO;
> +		opp = dev_pm_opp_find_freq_exact(pci->dev, freq_kbps * width,
> +						 true);
> +		if (!IS_ERR(opp)) {
> +			ret = dev_pm_opp_set_opp(pci->dev, opp);
> +			if (ret)
> +				dev_err(pci->dev, "Failed to set OPP for freq (%lu): %d\n",
> +					freq_kbps * width, ret);
> +			dev_pm_opp_put(opp);
> +		}
> +
> +	}
> +
> +}
> +EXPORT_SYMBOL_GPL(qcom_pcie_common_icc_update);

[...]

>  static int qcom_pcie_link_transition_count(struct seq_file *s, void *data)
>  {
>  	struct qcom_pcie *pcie = (struct qcom_pcie *)dev_get_drvdata(s->private);
> @@ -1561,6 +1472,18 @@ static int qcom_pcie_probe(struct platform_device *pdev)
>  		goto err_pm_runtime_put;
>  	}
>  
> +	pcie->icc_mem = qcom_pcie_common_icc_get_resource(pcie->pci, "pcie-mem");
> +	if (IS_ERR_OR_NULL(pcie->icc_mem)) {

Why are you checking for NULL here and below? ICC core will return NULL if the
path is not found in DT or ICC is disabled and it is important to not treat it
as an error to maintain DT backwards compatibility.

> +		ret = PTR_ERR(pcie->icc_mem);
> +		goto err_pm_runtime_put;
> +	}
> +
> +	pcie->icc_cpu = qcom_pcie_common_icc_get_resource(pcie->pci, "cpu-pcie");
> +	if (IS_ERR_OR_NULL(pcie->icc_cpu)) {
> +		ret = PTR_ERR(pcie->icc_cpu);
> +		goto err_pm_runtime_put;
> +	}
> +
>  	/* OPP table is optional */
>  	ret = devm_pm_opp_of_add_table(dev);
>  	if (ret && ret != -ENODEV) {
> @@ -1593,10 +1516,35 @@ static int qcom_pcie_probe(struct platform_device *pdev)
>  			goto err_pm_runtime_put;
>  		}
>  	} else {
> -		/* Skip ICC init if OPP is supported as it is handled by OPP */
> -		ret = qcom_pcie_icc_init(pcie);
> -		if (ret)
> +		/*
> +		 * Some Qualcomm platforms require interconnect bandwidth
> +		 * constraints to be set before enabling interconnect clocks
> +		 * Set an initial peak bandwidth corresponding to single-lane
> +		 * Gen 1 for the pcie-mem path.
> +		 */
> +		ret = qcom_pcie_common_icc_init(pcie->pci, pcie->icc_mem,
> +					QCOM_PCIE_LINK_SPEED_TO_BW(1));
> +		if (ret) {
> +			dev_err(pci->dev,
> +			"Failed to set bandwidth for PCIe-MEM interconnect path: %d\n",
> +			ret);
>  			goto err_pm_runtime_put;
> +		}
> +
> +		/*
> +		 * Since the CPU-PCIe path is only used for activities
> +		 * like register access of the host controller and
> +		 * endpoint Config/BAR space access, HW team has
> +		 * recommended to use a minimal bandwidth of 1KBps just to
> +		 * keep the path active.
> +		 */

Please wrap the comments to 80 columns. I don't know what column length you are
using here.

> +		ret = qcom_pcie_common_icc_init(pcie->pci, pcie->icc_cpu, kBps_to_icc(1));
> +		if (ret) {
> +			dev_err(pci->dev,
> +			"Failed to set bandwidth for CPU-PCIe interconnect path: %d\n",

You can make use of 100 column extension here and below.

- Mani
Manivannan Sadhasivam Aug. 25, 2024, 6:09 a.m. UTC | #5
On Wed, Aug 21, 2024 at 12:33:18PM -0500, Bjorn Helgaas wrote:
> On Wed, Aug 21, 2024 at 10:08:42AM -0700, Shashank Babu Chinta Venkata wrote:
> > Refactor common code from RC(Root Complex) and EP(End Point)
> > drivers and move them to a common driver. This acts as placeholder
> > for common source code for both drivers, thus avoiding duplication.
> 
> Much of this seems to be replacing qcom_pcie_icc_opp_update() and
> qcom_pcie_ep_icc_update() with qcom_pcie_common_icc_update().
> 
> That seems worthwhile and it would be helpful if the commit log called
> that out so we'd know what to look for in the patch.
> 
> I think the qcom_pcie_common_icc_init() rework would be more
> understandable if it were in its own patch and not mixed in here.
> 
> > +++ b/drivers/pci/controller/dwc/pcie-qcom-common.c
> > @@ -0,0 +1,88 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Copyright (c) 2014-2015, 2020 The Linux Foundation. All rights reserved.
> > + * Copyright (c) 2015, 2021 Linaro Limited.
> > + * Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved.
> > + *
> 
> Spurious blank line.
> 
> > + */
> 
> > +struct icc_path *qcom_pcie_common_icc_get_resource(struct dw_pcie *pci, const char *path)
> > +{
> > +	struct icc_path *icc_p;
> > +
> > +	icc_p = devm_of_icc_get(pci->dev, path);
> > +	return icc_p;
> 
>   return devm_of_icc_get(pci->dev, path);
> 
> > +}
> > +EXPORT_SYMBOL_GPL(qcom_pcie_common_icc_get_resource);
> > +
> > +int qcom_pcie_common_icc_init(struct dw_pcie *pci, struct icc_path *icc, u32 bandwidth)
> > +{
> > +	int ret;
> > +
> > +	ret = icc_set_bw(icc, 0, bandwidth);
> > +	if (ret) {
> > +		dev_err(pci->dev, "Failed to set interconnect bandwidth: %d\n",
> > +			ret);
> > +		return ret;
> > +	}
> 
> The callers also check and log similar messages.  I don't see the
> point.
> 
> > +
> > +	return 0;
> > +}
> > +EXPORT_SYMBOL_GPL(qcom_pcie_common_icc_init);
> 
> These both seem of dubious value.
> 
> > +++ b/drivers/pci/controller/dwc/pcie-qcom-common.h
> 
> Do we need "-common" in the filename?  Seems like "pcie-qcom.h" would
> be enough.  I *hope* we don't someday need both a "pcie-qcom.h and a
> "pcie-qcom-common.h"; that seems like it would really be overkill.
> 

I suggested the -common suffix since pcie-qcom is historically meant for RC
driver. So creating a common header with that name will create confusion since
we have a separate EP driver.

- Mani
Johan Hovold Aug. 26, 2024, 12:11 p.m. UTC | #6
On Wed, Aug 21, 2024 at 10:08:42AM -0700, Shashank Babu Chinta Venkata wrote:
> Refactor common code from RC(Root Complex) and EP(End Point)

Space before open parentheses, please (again).

> drivers and move them to a common driver. This acts as placeholder
> for common source code for both drivers, thus avoiding duplication.
> 
> Signed-off-by: Shashank Babu Chinta Venkata <quic_schintav@quicinc.com>

> diff --git a/drivers/pci/controller/dwc/pcie-qcom-common.c b/drivers/pci/controller/dwc/pcie-qcom-common.c
> new file mode 100644
> index 000000000000..1d8992147bba
> --- /dev/null
> +++ b/drivers/pci/controller/dwc/pcie-qcom-common.c
> @@ -0,0 +1,88 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2014-2015, 2020 The Linux Foundation. All rights reserved.
> + * Copyright (c) 2015, 2021 Linaro Limited.
> + * Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved.

Again, you can't claim copyright for just moving code around.

> + *
> + */
> +
> +#include <linux/pci.h>
> +#include <linux/interconnect.h>
> +#include <linux/pm_opp.h>
> +#include <linux/units.h>
> +
> +#include "../../pci.h"
> +#include "pcie-designware.h"
> +#include "pcie-qcom-common.h"
> +
> +struct icc_path *qcom_pcie_common_icc_get_resource(struct dw_pcie *pci, const char *path)
> +{
> +	struct icc_path *icc_p;
> +
> +	icc_p = devm_of_icc_get(pci->dev, path);
> +	return icc_p;
> +}
> +EXPORT_SYMBOL_GPL(qcom_pcie_common_icc_get_resource);
> +
> +int qcom_pcie_common_icc_init(struct dw_pcie *pci, struct icc_path *icc, u32 bandwidth)
> +{
> +	int ret;
> +
> +	ret = icc_set_bw(icc, 0, bandwidth);
> +	if (ret) {
> +		dev_err(pci->dev, "Failed to set interconnect bandwidth: %d\n",
> +			ret);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(qcom_pcie_common_icc_init);

As I already pointed out, these helpers seems to be of very little worth
and just hides what is really going on (e.g. that the resources are
device managed). Please consider dropping them.

> diff --git a/drivers/pci/controller/dwc/pcie-qcom-common.h b/drivers/pci/controller/dwc/pcie-qcom-common.h
> new file mode 100644
> index 000000000000..897fa18e618a
> --- /dev/null
> +++ b/drivers/pci/controller/dwc/pcie-qcom-common.h
> @@ -0,0 +1,15 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (c) 2014-2015, 2020 The Linux Foundation. All rights reserved.
> + * Copyright (c) 2015, 2021 Linaro Limited.
> + * Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved.

Same copyright issue here.

> + */
> +
> +#include "pcie-designware.h"
> +
> +#define QCOM_PCIE_LINK_SPEED_TO_BW(speed) \
> +		Mbps_to_icc(PCIE_SPEED2MBS_ENC(pcie_link_speed[speed]))
> +
> +struct icc_path *qcom_pcie_common_icc_get_resource(struct dw_pcie *pci, const char *path);
> +int qcom_pcie_common_icc_init(struct dw_pcie *pci, struct icc_path *icc_mem, u32 bandwidth);
> +void qcom_pcie_common_icc_update(struct dw_pcie *pci, struct icc_path *icc_mem);

Compile guards still missing, despite me pointing that out before.

> diff --git a/drivers/pci/controller/dwc/pcie-qcom-ep.c b/drivers/pci/controller/dwc/pcie-qcom-ep.c
> index 236229f66c80..e1860026e134 100644
> --- a/drivers/pci/controller/dwc/pcie-qcom-ep.c
> +++ b/drivers/pci/controller/dwc/pcie-qcom-ep.c
  
> -	ret = icc_set_bw(pcie_ep->icc_mem, 0, QCOM_PCIE_LINK_SPEED_TO_BW(1));
> +	ret = qcom_pcie_common_icc_init(pci, pcie_ep->icc_mem);

Does not even compile, as reported by the build bots.

> -static int qcom_pcie_icc_init(struct qcom_pcie *pcie)
> -{
> -	struct dw_pcie *pci = pcie->pci;
> -	int ret;
> -
> -	pcie->icc_mem = devm_of_icc_get(pci->dev, "pcie-mem");
> -	if (IS_ERR(pcie->icc_mem))
> -		return PTR_ERR(pcie->icc_mem);
> -
> -	pcie->icc_cpu = devm_of_icc_get(pci->dev, "cpu-pcie");
> -	if (IS_ERR(pcie->icc_cpu))
> -		return PTR_ERR(pcie->icc_cpu);
> -	/*
> -	 * Some Qualcomm platforms require interconnect bandwidth constraints
> -	 * to be set before enabling interconnect clocks.
> -	 *
> -	 * Set an initial peak bandwidth corresponding to single-lane Gen 1
> -	 * for the pcie-mem path.
> -	 */
> -	ret = icc_set_bw(pcie->icc_mem, 0, QCOM_PCIE_LINK_SPEED_TO_BW(1));
> -	if (ret) {
> -		dev_err(pci->dev, "Failed to set bandwidth for PCIe-MEM interconnect path: %d\n",
> -			ret);
> -		return ret;
> -	}
> -
> -	/*
> -	 * Since the CPU-PCIe path is only used for activities like register
> -	 * access of the host controller and endpoint Config/BAR space access,
> -	 * HW team has recommended to use a minimal bandwidth of 1KBps just to
> -	 * keep the path active.
> -	 */
> -	ret = icc_set_bw(pcie->icc_cpu, 0, kBps_to_icc(1));
> -	if (ret) {
> -		dev_err(pci->dev, "Failed to set bandwidth for CPU-PCIe interconnect path: %d\n",
> -			ret);
> -		icc_set_bw(pcie->icc_mem, 0, 0);
> -		return ret;
> -	}
> -
> -	return 0;
> -}

Just keep this function as is.

> -static void qcom_pcie_icc_opp_update(struct qcom_pcie *pcie)
> -{
> -	u32 offset, status, width, speed;
> -	struct dw_pcie *pci = pcie->pci;
> -	unsigned long freq_kbps;
> -	struct dev_pm_opp *opp;
> -	int ret, freq_mbps;
> -
> -	offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
> -	status = readw(pci->dbi_base + offset + PCI_EXP_LNKSTA);
> -
> -	/* Only update constraints if link is up. */
> -	if (!(status & PCI_EXP_LNKSTA_DLLLA))
> -		return;
> -
> -	speed = FIELD_GET(PCI_EXP_LNKSTA_CLS, status);
> -	width = FIELD_GET(PCI_EXP_LNKSTA_NLW, status);
> -
> -	if (pcie->icc_mem) {
> -		ret = icc_set_bw(pcie->icc_mem, 0,
> -				 width * QCOM_PCIE_LINK_SPEED_TO_BW(speed));
> -		if (ret) {
> -			dev_err(pci->dev, "Failed to set bandwidth for PCIe-MEM interconnect path: %d\n",
> -				ret);
> -		}
> -	} else {
> -		freq_mbps = pcie_dev_speed_mbps(pcie_link_speed[speed]);
> -		if (freq_mbps < 0)
> -			return;
> -
> -		freq_kbps = freq_mbps * KILO;
> -		opp = dev_pm_opp_find_freq_exact(pci->dev, freq_kbps * width,
> -						 true);
> -		if (!IS_ERR(opp)) {
> -			ret = dev_pm_opp_set_opp(pci->dev, opp);
> -			if (ret)
> -				dev_err(pci->dev, "Failed to set OPP for freq (%lu): %d\n",
> -					freq_kbps * width, ret);
> -			dev_pm_opp_put(opp);
> -		}
> -	}
> -}

Maybe it's worth trying to generalise this, but probably not. Either
way, I don't think the gen4 stability *fixes* should depend on this (the
gen4 nvme link on x1e80100 is currently broken and depends on the later
changes in this series).

Please consider dropping all this, mostly bogus, refactoring and just
get the gen4 fixes in first.

> -
>  static int qcom_pcie_link_transition_count(struct seq_file *s, void *data)
>  {
>  	struct qcom_pcie *pcie = (struct qcom_pcie *)dev_get_drvdata(s->private);
> @@ -1561,6 +1472,18 @@ static int qcom_pcie_probe(struct platform_device *pdev)
>  		goto err_pm_runtime_put;
>  	}
>  
> +	pcie->icc_mem = qcom_pcie_common_icc_get_resource(pcie->pci, "pcie-mem");
> +	if (IS_ERR_OR_NULL(pcie->icc_mem)) {

This will break machines which don't have this path. NULL is valid here.

> +		ret = PTR_ERR(pcie->icc_mem);
> +		goto err_pm_runtime_put;
> +	}
> +
> +	pcie->icc_cpu = qcom_pcie_common_icc_get_resource(pcie->pci, "cpu-pcie");
> +	if (IS_ERR_OR_NULL(pcie->icc_cpu)) {

Same here.

> +		ret = PTR_ERR(pcie->icc_cpu);
> +		goto err_pm_runtime_put;
> +	}
> +
>  	/* OPP table is optional */
>  	ret = devm_pm_opp_of_add_table(dev);
>  	if (ret && ret != -ENODEV) {

> @@ -1681,7 +1629,8 @@ static int qcom_pcie_suspend_noirq(struct device *dev)
>  	if (pm_suspend_target_state != PM_SUSPEND_MEM) {
>  		ret = icc_disable(pcie->icc_cpu);
>  		if (ret)
> -			dev_err(dev, "Failed to disable CPU-PCIe interconnect path: %d\n", ret);
> +			dev_err(dev,
> +			"Failed to disable CPU-PCIe interconnect path: %d\n", ret);

Unrelated, bogus change.

Johan
diff mbox series

Patch

diff --git a/MAINTAINERS b/MAINTAINERS
index c0a62489be56..ef3e62677e9f 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2785,6 +2785,7 @@  F:	drivers/iommu/msm*
 F:	drivers/mfd/ssbi.c
 F:	drivers/mmc/host/mmci_qcom*
 F:	drivers/mmc/host/sdhci-msm.c
+F:	drivers/pci/controller/dwc/pcie-qcom-common.c
 F:	drivers/pci/controller/dwc/pcie-qcom.c
 F:	drivers/phy/qualcomm/
 F:	drivers/power/*/msm*
@@ -17844,6 +17845,7 @@  M:	Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
 L:	linux-pci@vger.kernel.org
 L:	linux-arm-msm@vger.kernel.org
 S:	Maintained
+F:	drivers/pci/controller/dwc/pcie-qcom-common.c
 F:	drivers/pci/controller/dwc/pcie-qcom.c
 
 PCIE DRIVER FOR ROCKCHIP
@@ -17880,6 +17882,7 @@  L:	linux-pci@vger.kernel.org
 L:	linux-arm-msm@vger.kernel.org
 S:	Maintained
 F:	Documentation/devicetree/bindings/pci/qcom,pcie-ep.yaml
+F:	drivers/pci/controller/dwc/pcie-qcom-common.c
 F:	drivers/pci/controller/dwc/pcie-qcom-ep.c
 
 PCMCIA SUBSYSTEM
diff --git a/drivers/pci/controller/dwc/Kconfig b/drivers/pci/controller/dwc/Kconfig
index 4c38181acffa..b6d6778b0698 100644
--- a/drivers/pci/controller/dwc/Kconfig
+++ b/drivers/pci/controller/dwc/Kconfig
@@ -265,12 +265,16 @@  config PCIE_DW_PLAT_EP
 	  order to enable device-specific features PCI_DW_PLAT_EP must be
 	  selected.
 
+config PCIE_QCOM_COMMON
+	bool
+
 config PCIE_QCOM
 	bool "Qualcomm PCIe controller (host mode)"
 	depends on OF && (ARCH_QCOM || COMPILE_TEST)
 	depends on PCI_MSI
 	select PCIE_DW_HOST
 	select CRC8
+	select PCIE_QCOM_COMMON
 	help
 	  Say Y here to enable PCIe controller support on Qualcomm SoCs. The
 	  PCIe controller uses the DesignWare core plus Qualcomm-specific
@@ -281,6 +285,7 @@  config PCIE_QCOM_EP
 	depends on OF && (ARCH_QCOM || COMPILE_TEST)
 	depends on PCI_ENDPOINT
 	select PCIE_DW_EP
+	select PCIE_QCOM_COMMON
 	help
 	  Say Y here to enable support for the PCIe controllers on Qualcomm SoCs
 	  to work in endpoint mode. The PCIe controller uses the DesignWare core
diff --git a/drivers/pci/controller/dwc/Makefile b/drivers/pci/controller/dwc/Makefile
index ec215b3d6191..82e51ba11031 100644
--- a/drivers/pci/controller/dwc/Makefile
+++ b/drivers/pci/controller/dwc/Makefile
@@ -14,6 +14,7 @@  obj-$(CONFIG_PCI_LAYERSCAPE) += pci-layerscape.o
 obj-$(CONFIG_PCI_LAYERSCAPE_EP) += pci-layerscape-ep.o
 obj-$(CONFIG_PCIE_QCOM) += pcie-qcom.o
 obj-$(CONFIG_PCIE_QCOM_EP) += pcie-qcom-ep.o
+obj-$(CONFIG_PCIE_QCOM_COMMON) += pcie-qcom-common.o
 obj-$(CONFIG_PCIE_ARMADA_8K) += pcie-armada8k.o
 obj-$(CONFIG_PCIE_ARTPEC6) += pcie-artpec6.o
 obj-$(CONFIG_PCIE_ROCKCHIP_DW) += pcie-dw-rockchip.o
diff --git a/drivers/pci/controller/dwc/pcie-qcom-common.c b/drivers/pci/controller/dwc/pcie-qcom-common.c
new file mode 100644
index 000000000000..1d8992147bba
--- /dev/null
+++ b/drivers/pci/controller/dwc/pcie-qcom-common.c
@@ -0,0 +1,88 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2014-2015, 2020 The Linux Foundation. All rights reserved.
+ * Copyright (c) 2015, 2021 Linaro Limited.
+ * Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved.
+ *
+ */
+
+#include <linux/pci.h>
+#include <linux/interconnect.h>
+#include <linux/pm_opp.h>
+#include <linux/units.h>
+
+#include "../../pci.h"
+#include "pcie-designware.h"
+#include "pcie-qcom-common.h"
+
+struct icc_path *qcom_pcie_common_icc_get_resource(struct dw_pcie *pci, const char *path)
+{
+	struct icc_path *icc_p;
+
+	icc_p = devm_of_icc_get(pci->dev, path);
+	return icc_p;
+}
+EXPORT_SYMBOL_GPL(qcom_pcie_common_icc_get_resource);
+
+int qcom_pcie_common_icc_init(struct dw_pcie *pci, struct icc_path *icc, u32 bandwidth)
+{
+	int ret;
+
+	ret = icc_set_bw(icc, 0, bandwidth);
+	if (ret) {
+		dev_err(pci->dev, "Failed to set interconnect bandwidth: %d\n",
+			ret);
+		return ret;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(qcom_pcie_common_icc_init);
+
+void qcom_pcie_common_icc_update(struct dw_pcie *pci, struct icc_path *icc_mem)
+{
+	u32 offset, status, width, speed;
+	unsigned long freq_kbps;
+	struct dev_pm_opp *opp;
+	int ret, freq_mbps;
+
+	if (!icc_mem)
+		return;
+
+	offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
+	status = readw(pci->dbi_base + offset + PCI_EXP_LNKSTA);
+
+	/* Only update constraints if link is up. */
+	if (!(status & PCI_EXP_LNKSTA_DLLLA))
+		return;
+
+	speed = FIELD_GET(PCI_EXP_LNKSTA_CLS, status);
+	width = FIELD_GET(PCI_EXP_LNKSTA_NLW, status);
+
+	if (icc_mem) {
+		ret = icc_set_bw(icc_mem, 0,
+				 width * QCOM_PCIE_LINK_SPEED_TO_BW(speed));
+		if (ret) {
+			dev_err(pci->dev, "Failed to set bandwidth for PCIe-MEM interconnect path: %d\n",
+				ret);
+		}
+	} else {
+		freq_mbps = pcie_dev_speed_mbps(pcie_link_speed[speed]);
+		if (freq_mbps < 0)
+			return;
+
+		freq_kbps = freq_mbps * KILO;
+		opp = dev_pm_opp_find_freq_exact(pci->dev, freq_kbps * width,
+						 true);
+		if (!IS_ERR(opp)) {
+			ret = dev_pm_opp_set_opp(pci->dev, opp);
+			if (ret)
+				dev_err(pci->dev, "Failed to set OPP for freq (%lu): %d\n",
+					freq_kbps * width, ret);
+			dev_pm_opp_put(opp);
+		}
+
+	}
+
+}
+EXPORT_SYMBOL_GPL(qcom_pcie_common_icc_update);
diff --git a/drivers/pci/controller/dwc/pcie-qcom-common.h b/drivers/pci/controller/dwc/pcie-qcom-common.h
new file mode 100644
index 000000000000..897fa18e618a
--- /dev/null
+++ b/drivers/pci/controller/dwc/pcie-qcom-common.h
@@ -0,0 +1,15 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2014-2015, 2020 The Linux Foundation. All rights reserved.
+ * Copyright (c) 2015, 2021 Linaro Limited.
+ * Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#include "pcie-designware.h"
+
+#define QCOM_PCIE_LINK_SPEED_TO_BW(speed) \
+		Mbps_to_icc(PCIE_SPEED2MBS_ENC(pcie_link_speed[speed]))
+
+struct icc_path *qcom_pcie_common_icc_get_resource(struct dw_pcie *pci, const char *path);
+int qcom_pcie_common_icc_init(struct dw_pcie *pci, struct icc_path *icc_mem, u32 bandwidth);
+void qcom_pcie_common_icc_update(struct dw_pcie *pci, struct icc_path *icc_mem);
diff --git a/drivers/pci/controller/dwc/pcie-qcom-ep.c b/drivers/pci/controller/dwc/pcie-qcom-ep.c
index 236229f66c80..e1860026e134 100644
--- a/drivers/pci/controller/dwc/pcie-qcom-ep.c
+++ b/drivers/pci/controller/dwc/pcie-qcom-ep.c
@@ -25,6 +25,7 @@ 
 
 #include "../../pci.h"
 #include "pcie-designware.h"
+#include "pcie-qcom-common.h"
 
 /* PARF registers */
 #define PARF_SYS_CTRL				0x00
@@ -142,9 +143,6 @@ 
 #define CORE_RESET_TIME_US_MAX			1005
 #define WAKE_DELAY_US				2000 /* 2 ms */
 
-#define QCOM_PCIE_LINK_SPEED_TO_BW(speed) \
-		Mbps_to_icc(PCIE_SPEED2MBS_ENC(pcie_link_speed[speed]))
-
 #define to_pcie_ep(x)				dev_get_drvdata((x)->dev)
 
 enum qcom_pcie_ep_link_status {
@@ -295,28 +293,6 @@  static void qcom_pcie_dw_write_dbi2(struct dw_pcie *pci, void __iomem *base,
 	writel(0, pcie_ep->elbi + ELBI_CS2_ENABLE);
 }
 
-static void qcom_pcie_ep_icc_update(struct qcom_pcie_ep *pcie_ep)
-{
-	struct dw_pcie *pci = &pcie_ep->pci;
-	u32 offset, status;
-	int speed, width;
-	int ret;
-
-	if (!pcie_ep->icc_mem)
-		return;
-
-	offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
-	status = readw(pci->dbi_base + offset + PCI_EXP_LNKSTA);
-
-	speed = FIELD_GET(PCI_EXP_LNKSTA_CLS, status);
-	width = FIELD_GET(PCI_EXP_LNKSTA_NLW, status);
-
-	ret = icc_set_bw(pcie_ep->icc_mem, 0, width * QCOM_PCIE_LINK_SPEED_TO_BW(speed));
-	if (ret)
-		dev_err(pci->dev, "failed to set interconnect bandwidth: %d\n",
-			ret);
-}
-
 static int qcom_pcie_enable_resources(struct qcom_pcie_ep *pcie_ep)
 {
 	struct dw_pcie *pci = &pcie_ep->pci;
@@ -342,14 +318,7 @@  static int qcom_pcie_enable_resources(struct qcom_pcie_ep *pcie_ep)
 	if (ret)
 		goto err_phy_exit;
 
-	/*
-	 * Some Qualcomm platforms require interconnect bandwidth constraints
-	 * to be set before enabling interconnect clocks.
-	 *
-	 * Set an initial peak bandwidth corresponding to single-lane Gen 1
-	 * for the pcie-mem path.
-	 */
-	ret = icc_set_bw(pcie_ep->icc_mem, 0, QCOM_PCIE_LINK_SPEED_TO_BW(1));
+	ret = qcom_pcie_common_icc_init(pci, pcie_ep->icc_mem);
 	if (ret) {
 		dev_err(pci->dev, "failed to set interconnect bandwidth: %d\n",
 			ret);
@@ -633,7 +602,7 @@  static int qcom_pcie_ep_get_resources(struct platform_device *pdev,
 	if (IS_ERR(pcie_ep->phy))
 		ret = PTR_ERR(pcie_ep->phy);
 
-	pcie_ep->icc_mem = devm_of_icc_get(dev, "pcie-mem");
+	pcie_ep->icc_mem = qcom_pcie_common_icc_get_resource(&pcie_ep->pci, "pcie-mem");
 	if (IS_ERR(pcie_ep->icc_mem))
 		ret = PTR_ERR(pcie_ep->icc_mem);
 
@@ -660,7 +629,7 @@  static irqreturn_t qcom_pcie_ep_global_irq_thread(int irq, void *data)
 	} else if (FIELD_GET(PARF_INT_ALL_BME, status)) {
 		dev_dbg(dev, "Received Bus Master Enable event\n");
 		pcie_ep->link_status = QCOM_PCIE_EP_LINK_ENABLED;
-		qcom_pcie_ep_icc_update(pcie_ep);
+		qcom_pcie_common_icc_update(pci, pcie_ep->icc_mem);
 		pci_epc_bus_master_enable_notify(pci->ep.epc);
 	} else if (FIELD_GET(PARF_INT_ALL_PM_TURNOFF, status)) {
 		dev_dbg(dev, "Received PM Turn-off event! Entering L23\n");
diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
index 0180edf3310e..ee32590f1506 100644
--- a/drivers/pci/controller/dwc/pcie-qcom.c
+++ b/drivers/pci/controller/dwc/pcie-qcom.c
@@ -31,9 +31,9 @@ 
 #include <linux/reset.h>
 #include <linux/slab.h>
 #include <linux/types.h>
-#include <linux/units.h>
 
 #include "../../pci.h"
+#include "pcie-qcom-common.h"
 #include "pcie-designware.h"
 
 /* PARF registers */
@@ -158,9 +158,6 @@ 
 
 #define QCOM_PCIE_CRC8_POLYNOMIAL		(BIT(2) | BIT(1) | BIT(0))
 
-#define QCOM_PCIE_LINK_SPEED_TO_BW(speed) \
-		Mbps_to_icc(PCIE_SPEED2MBS_ENC(pcie_link_speed[speed]))
-
 struct qcom_pcie_resources_1_0_0 {
 	struct clk_bulk_data *clks;
 	int num_clks;
@@ -1365,92 +1362,6 @@  static const struct dw_pcie_ops dw_pcie_ops = {
 	.start_link = qcom_pcie_start_link,
 };
 
-static int qcom_pcie_icc_init(struct qcom_pcie *pcie)
-{
-	struct dw_pcie *pci = pcie->pci;
-	int ret;
-
-	pcie->icc_mem = devm_of_icc_get(pci->dev, "pcie-mem");
-	if (IS_ERR(pcie->icc_mem))
-		return PTR_ERR(pcie->icc_mem);
-
-	pcie->icc_cpu = devm_of_icc_get(pci->dev, "cpu-pcie");
-	if (IS_ERR(pcie->icc_cpu))
-		return PTR_ERR(pcie->icc_cpu);
-	/*
-	 * Some Qualcomm platforms require interconnect bandwidth constraints
-	 * to be set before enabling interconnect clocks.
-	 *
-	 * Set an initial peak bandwidth corresponding to single-lane Gen 1
-	 * for the pcie-mem path.
-	 */
-	ret = icc_set_bw(pcie->icc_mem, 0, QCOM_PCIE_LINK_SPEED_TO_BW(1));
-	if (ret) {
-		dev_err(pci->dev, "Failed to set bandwidth for PCIe-MEM interconnect path: %d\n",
-			ret);
-		return ret;
-	}
-
-	/*
-	 * Since the CPU-PCIe path is only used for activities like register
-	 * access of the host controller and endpoint Config/BAR space access,
-	 * HW team has recommended to use a minimal bandwidth of 1KBps just to
-	 * keep the path active.
-	 */
-	ret = icc_set_bw(pcie->icc_cpu, 0, kBps_to_icc(1));
-	if (ret) {
-		dev_err(pci->dev, "Failed to set bandwidth for CPU-PCIe interconnect path: %d\n",
-			ret);
-		icc_set_bw(pcie->icc_mem, 0, 0);
-		return ret;
-	}
-
-	return 0;
-}
-
-static void qcom_pcie_icc_opp_update(struct qcom_pcie *pcie)
-{
-	u32 offset, status, width, speed;
-	struct dw_pcie *pci = pcie->pci;
-	unsigned long freq_kbps;
-	struct dev_pm_opp *opp;
-	int ret, freq_mbps;
-
-	offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
-	status = readw(pci->dbi_base + offset + PCI_EXP_LNKSTA);
-
-	/* Only update constraints if link is up. */
-	if (!(status & PCI_EXP_LNKSTA_DLLLA))
-		return;
-
-	speed = FIELD_GET(PCI_EXP_LNKSTA_CLS, status);
-	width = FIELD_GET(PCI_EXP_LNKSTA_NLW, status);
-
-	if (pcie->icc_mem) {
-		ret = icc_set_bw(pcie->icc_mem, 0,
-				 width * QCOM_PCIE_LINK_SPEED_TO_BW(speed));
-		if (ret) {
-			dev_err(pci->dev, "Failed to set bandwidth for PCIe-MEM interconnect path: %d\n",
-				ret);
-		}
-	} else {
-		freq_mbps = pcie_dev_speed_mbps(pcie_link_speed[speed]);
-		if (freq_mbps < 0)
-			return;
-
-		freq_kbps = freq_mbps * KILO;
-		opp = dev_pm_opp_find_freq_exact(pci->dev, freq_kbps * width,
-						 true);
-		if (!IS_ERR(opp)) {
-			ret = dev_pm_opp_set_opp(pci->dev, opp);
-			if (ret)
-				dev_err(pci->dev, "Failed to set OPP for freq (%lu): %d\n",
-					freq_kbps * width, ret);
-			dev_pm_opp_put(opp);
-		}
-	}
-}
-
 static int qcom_pcie_link_transition_count(struct seq_file *s, void *data)
 {
 	struct qcom_pcie *pcie = (struct qcom_pcie *)dev_get_drvdata(s->private);
@@ -1561,6 +1472,18 @@  static int qcom_pcie_probe(struct platform_device *pdev)
 		goto err_pm_runtime_put;
 	}
 
+	pcie->icc_mem = qcom_pcie_common_icc_get_resource(pcie->pci, "pcie-mem");
+	if (IS_ERR_OR_NULL(pcie->icc_mem)) {
+		ret = PTR_ERR(pcie->icc_mem);
+		goto err_pm_runtime_put;
+	}
+
+	pcie->icc_cpu = qcom_pcie_common_icc_get_resource(pcie->pci, "cpu-pcie");
+	if (IS_ERR_OR_NULL(pcie->icc_cpu)) {
+		ret = PTR_ERR(pcie->icc_cpu);
+		goto err_pm_runtime_put;
+	}
+
 	/* OPP table is optional */
 	ret = devm_pm_opp_of_add_table(dev);
 	if (ret && ret != -ENODEV) {
@@ -1593,10 +1516,35 @@  static int qcom_pcie_probe(struct platform_device *pdev)
 			goto err_pm_runtime_put;
 		}
 	} else {
-		/* Skip ICC init if OPP is supported as it is handled by OPP */
-		ret = qcom_pcie_icc_init(pcie);
-		if (ret)
+		/*
+		 * Some Qualcomm platforms require interconnect bandwidth
+		 * constraints to be set before enabling interconnect clocks
+		 * Set an initial peak bandwidth corresponding to single-lane
+		 * Gen 1 for the pcie-mem path.
+		 */
+		ret = qcom_pcie_common_icc_init(pcie->pci, pcie->icc_mem,
+					QCOM_PCIE_LINK_SPEED_TO_BW(1));
+		if (ret) {
+			dev_err(pci->dev,
+			"Failed to set bandwidth for PCIe-MEM interconnect path: %d\n",
+			ret);
 			goto err_pm_runtime_put;
+		}
+
+		/*
+		 * Since the CPU-PCIe path is only used for activities
+		 * like register access of the host controller and
+		 * endpoint Config/BAR space access, HW team has
+		 * recommended to use a minimal bandwidth of 1KBps just to
+		 * keep the path active.
+		 */
+		ret = qcom_pcie_common_icc_init(pcie->pci, pcie->icc_cpu, kBps_to_icc(1));
+		if (ret) {
+			dev_err(pci->dev,
+			"Failed to set bandwidth for CPU-PCIe interconnect path: %d\n",
+			ret);
+			goto err_pm_runtime_put;
+		}
 	}
 
 	ret = pcie->cfg->ops->get_resources(pcie);
@@ -1617,7 +1565,7 @@  static int qcom_pcie_probe(struct platform_device *pdev)
 		goto err_phy_exit;
 	}
 
-	qcom_pcie_icc_opp_update(pcie);
+	qcom_pcie_common_icc_update(pcie->pci, pcie->icc_mem);
 
 	if (pcie->mhi)
 		qcom_pcie_init_debugfs(pcie);
@@ -1681,7 +1629,8 @@  static int qcom_pcie_suspend_noirq(struct device *dev)
 	if (pm_suspend_target_state != PM_SUSPEND_MEM) {
 		ret = icc_disable(pcie->icc_cpu);
 		if (ret)
-			dev_err(dev, "Failed to disable CPU-PCIe interconnect path: %d\n", ret);
+			dev_err(dev,
+			"Failed to disable CPU-PCIe interconnect path: %d\n", ret);
 
 		if (!pcie->icc_mem)
 			dev_pm_opp_set_opp(pcie->pci->dev, NULL);
@@ -1710,7 +1659,7 @@  static int qcom_pcie_resume_noirq(struct device *dev)
 		pcie->suspended = false;
 	}
 
-	qcom_pcie_icc_opp_update(pcie);
+	qcom_pcie_common_icc_update(pcie->pci, pcie->icc_mem);
 
 	return 0;
 }