[PATCH 00/15] PCI: brcmstb: enable PCIe for STB chips

[PATCH 00/15] PCI: brcmstb: enable PCIe for STB chips

[Jim Quinlan]

This patchset expands the usefulness of the Broadcom Settop Box PCIe
controller by building upon the PCIe driver used currently by the
Raspbery Pi.  Other forms of this patchset were submitted by me years
ago and not accepted; the major sticking point was the code required
for the DMA remapping needed for the PCIe driver to work [1].

There have been many changes to the DMA and OF subsystems since that
time, making a cleaner and less intrusive patchset possible.  This
patchset implements a generalization of "dev->dma_pfn_offset", except
that instead of a single scalar offset it provides for multiple
offsets via a function which depends upon the "dma-ranges" property of
the PCIe host controller.  This is required for proper functionality
of the BrcmSTB PCIe controller and possibly some other devices.

[1] https://lore.kernel.org/linux-arm-kernel/1516058925-46522-5-git-send-email-jim2101024@gmail.com/

Jim Quinlan (15):
  PCI: brcmstb: PCIE_BRCMSTB depends on ARCH_BRCMSTB
  ahci_brcm: fix use of BCM7216 reset controller
  dt-bindings: PCI: Add bindings for more Brcmstb chips
  PCI: brcmstb: Add compatibily of other chips
  PCI: brcmstb: Add suspend and resume pm_ops
  PCI: brcmstb: Asserting PERST is different for 7278
  PCI: brcmstb: Add control of rescal reset
  of: Include a dev param in of_dma_get_range()
  device core: Add ability to handle multiple dma offsets
  dma-direct: Invoke dma offset func if needed
  arm: dma-mapping: Invoke dma offset func if needed
  PCI: brcmstb: Set internal memory viewport sizes
  PCI: brcmstb: Accommodate MSI for older chips
  PCI: brcmstb: Set bus max burst side by chip type
  PCI: brcmstb: add compatilbe chips to match list

 .../bindings/pci/brcm,stb-pcie.yaml           |  40 +-
 arch/arm/include/asm/dma-mapping.h            |  17 +-
 drivers/ata/ahci_brcm.c                       |  14 +-
 drivers/of/address.c                          |  54 ++-
 drivers/of/device.c                           |   2 +-
 drivers/of/of_private.h                       |   8 +-
 drivers/pci/controller/Kconfig                |   4 +-
 drivers/pci/controller/pcie-brcmstb.c         | 403 +++++++++++++++---
 include/linux/device.h                        |   9 +-
 include/linux/dma-direct.h                    |  16 +
 include/linux/dma-mapping.h                   |  44 ++
 kernel/dma/Kconfig                            |  12 +
 12 files changed, 542 insertions(+), 81 deletions(-)

-- 
2.17.1

[PATCH 02/15] ahci_brcm: fix use of BCM7216 reset controller

[Jim Quinlan]

From: Jim Quinlan <jquinlan@broadcom.com>

A reset controller "rescal" is shared between the AHCI driver
and the PCIe driver for the BrcmSTB 7216 chip.  The code is
modified to allow this sharing and to deassert() properly.

Signed-off-by: Jim Quinlan <jquinlan@broadcom.com>
---
 drivers/ata/ahci_brcm.c | 14 +++++---------
 1 file changed, 5 insertions(+), 9 deletions(-)

diff --git a/drivers/ata/ahci_brcm.c b/drivers/ata/ahci_brcm.c
index 6853dbb4131d..a3c32fc29e9c 100644
--- a/drivers/ata/ahci_brcm.c
+++ b/drivers/ata/ahci_brcm.c
@@ -428,7 +428,6 @@ static int brcm_ahci_probe(struct platform_device *pdev)
 {
 	const struct of_device_id *of_id;
 	struct device *dev = &pdev->dev;
-	const char *reset_name = NULL;
 	struct brcm_ahci_priv *priv;
 	struct ahci_host_priv *hpriv;
 	struct resource *res;
@@ -452,11 +451,11 @@ static int brcm_ahci_probe(struct platform_device *pdev)
 
 	/* Reset is optional depending on platform and named differently */
 	if (priv->version == BRCM_SATA_BCM7216)
-		reset_name = "rescal";
+		priv->rcdev = devm_reset_control_get_shared(&pdev->dev,
+							    "rescal");
 	else
-		reset_name = "ahci";
-
-	priv->rcdev = devm_reset_control_get_optional(&pdev->dev, reset_name);
+		priv->rcdev = devm_reset_control_get_optional(&pdev->dev,
+							      "ahci");
 	if (IS_ERR(priv->rcdev))
 		return PTR_ERR(priv->rcdev);
 
@@ -479,10 +478,7 @@ static int brcm_ahci_probe(struct platform_device *pdev)
 		break;
 	}
 
-	if (priv->version == BRCM_SATA_BCM7216)
-		ret = reset_control_reset(priv->rcdev);
-	else
-		ret = reset_control_deassert(priv->rcdev);
+	ret = reset_control_deassert(priv->rcdev);
 	if (ret)
 		return ret;
 
-- 
2.17.1

Re: [PATCH 02/15] ahci_brcm: fix use of BCM7216 reset controller

[Philipp Zabel]

Hi Jim,

On Tue, May 19, 2020 at 04:34:00PM -0400, Jim Quinlan wrote:
> From: Jim Quinlan <jquinlan@broadcom.com>
> 
> A reset controller "rescal" is shared between the AHCI driver
> and the PCIe driver for the BrcmSTB 7216 chip.  The code is
> modified to allow this sharing and to deassert() properly.
> 
> Signed-off-by: Jim Quinlan <jquinlan@broadcom.com>
> ---
>  drivers/ata/ahci_brcm.c | 14 +++++---------
>  1 file changed, 5 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/ata/ahci_brcm.c b/drivers/ata/ahci_brcm.c
> index 6853dbb4131d..a3c32fc29e9c 100644
> --- a/drivers/ata/ahci_brcm.c
> +++ b/drivers/ata/ahci_brcm.c
> @@ -428,7 +428,6 @@ static int brcm_ahci_probe(struct platform_device *pdev)
>  {
>  	const struct of_device_id *of_id;
>  	struct device *dev = &pdev->dev;
> -	const char *reset_name = NULL;
>  	struct brcm_ahci_priv *priv;
>  	struct ahci_host_priv *hpriv;
>  	struct resource *res;
> @@ -452,11 +451,11 @@ static int brcm_ahci_probe(struct platform_device *pdev)
>  
>  	/* Reset is optional depending on platform and named differently */
>  	if (priv->version == BRCM_SATA_BCM7216)
> -		reset_name = "rescal";
> +		priv->rcdev = devm_reset_control_get_shared(&pdev->dev,
> +							    "rescal");

With this change the "rescal" reset control is not optional anymore.
Please use devm_reset_control_get_optional_shared() or change the
comment.

>  	else
> -		reset_name = "ahci";
> -
> -	priv->rcdev = devm_reset_control_get_optional(&pdev->dev, reset_name);
> +		priv->rcdev = devm_reset_control_get_optional(&pdev->dev,
> +							      "ahci");

You can use devm_reset_control_get_optional_exclusive() here to make it
clear this requests an exclusive control.

regards
Philipp

Re: [PATCH 00/15] PCI: brcmstb: enable PCIe for STB chips

[Bjorn Helgaas]

On Tue, May 19, 2020 at 04:33:58PM -0400, Jim Quinlan wrote:
> This patchset expands the usefulness of the Broadcom Settop Box PCIe
> controller by building upon the PCIe driver used currently by the
> Raspbery Pi.  Other forms of this patchset were submitted by me years
> ago and not accepted; the major sticking point was the code required
> for the DMA remapping needed for the PCIe driver to work [1].
> 
> There have been many changes to the DMA and OF subsystems since that
> time, making a cleaner and less intrusive patchset possible.  This
> patchset implements a generalization of "dev->dma_pfn_offset", except
> that instead of a single scalar offset it provides for multiple
> offsets via a function which depends upon the "dma-ranges" property of
> the PCIe host controller.  This is required for proper functionality
> of the BrcmSTB PCIe controller and possibly some other devices.
> 
> [1] https://lore.kernel.org/linux-arm-kernel/1516058925-46522-5-git-send-email-jim2101024@gmail.com/
> 
> Jim Quinlan (15):
>   PCI: brcmstb: PCIE_BRCMSTB depends on ARCH_BRCMSTB
>   ahci_brcm: fix use of BCM7216 reset controller
>   dt-bindings: PCI: Add bindings for more Brcmstb chips
>   PCI: brcmstb: Add compatibily of other chips
>   PCI: brcmstb: Add suspend and resume pm_ops
>   PCI: brcmstb: Asserting PERST is different for 7278
>   PCI: brcmstb: Add control of rescal reset
>   of: Include a dev param in of_dma_get_range()
>   device core: Add ability to handle multiple dma offsets
>   dma-direct: Invoke dma offset func if needed
>   arm: dma-mapping: Invoke dma offset func if needed
>   PCI: brcmstb: Set internal memory viewport sizes
>   PCI: brcmstb: Accommodate MSI for older chips
>   PCI: brcmstb: Set bus max burst side by chip type
>   PCI: brcmstb: add compatilbe chips to match list

If you have occasion to post a v2 for other reasons,

s/PCIE_BRCMSTB depends on ARCH_BRCMSTB/Allow PCIE_BRCMSTB on ARCH_BRCMSTB also/
s/ahci_brcm: fix use of BCM7216 reset controller/ata: ahci_brcm: Fix .../
s/Add compatibily of other chips/Add bcm7278 register info/
s/Asserting PERST is different for 7278/Add bcm7278 PERST support/
s/Set bus max burst side/Set bus max burst size/
s/add compatilbe chips.*/Add bcm7211, bcm7216, bcm7445, bcm7278 to match list/

Rewrap commit logs to use full 75 character lines (to allow for the 4
spaces added by git log).

In commit logs, s/This commit// (use imperative mood instead).

In "Accommodate MSI for older chips" commit log, s/commont/common/.

>  .../bindings/pci/brcm,stb-pcie.yaml           |  40 +-
>  arch/arm/include/asm/dma-mapping.h            |  17 +-
>  drivers/ata/ahci_brcm.c                       |  14 +-
>  drivers/of/address.c                          |  54 ++-
>  drivers/of/device.c                           |   2 +-
>  drivers/of/of_private.h                       |   8 +-
>  drivers/pci/controller/Kconfig                |   4 +-
>  drivers/pci/controller/pcie-brcmstb.c         | 403 +++++++++++++++---
>  include/linux/device.h                        |   9 +-
>  include/linux/dma-direct.h                    |  16 +
>  include/linux/dma-mapping.h                   |  44 ++
>  kernel/dma/Kconfig                            |  12 +
>  12 files changed, 542 insertions(+), 81 deletions(-)
> 
> -- 
> 2.17.1
>