[PATCH v5 02/10] PCI: imx6: Add ref clock for i.MX95 PCIe

Richard Zhu posted 10 patches 3 weeks, 3 days ago
There is a newer version of this series
[PATCH v5 02/10] PCI: imx6: Add ref clock for i.MX95 PCIe
Posted by Richard Zhu 3 weeks, 3 days ago
Add "ref" clock to enable reference clock. To avoid the DT
compatibility, i.MX95 REF clock might be optional. Replace the
devm_clk_bulk_get() by devm_clk_bulk_get_optional() to fetch
i.MX95 PCIe clocks in driver.

If use external clock, ref clock should point to external reference.

If use internal clock, CREF_EN in LAST_TO_REG controls reference output,
which implement in drivers/clk/imx/clk-imx95-blk-ctl.c.

Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
---
 drivers/pci/controller/dwc/pci-imx6.c | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index 808d1f105417..73cb69ba8933 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -82,6 +82,7 @@ enum imx_pcie_variants {
 #define IMX_PCIE_FLAG_HAS_SERDES		BIT(6)
 #define IMX_PCIE_FLAG_SUPPORT_64BIT		BIT(7)
 #define IMX_PCIE_FLAG_CPU_ADDR_FIXUP		BIT(8)
+#define IMX_PCIE_FLAG_CLOCKS_OPTIONAL		BIT(9)
 
 #define imx_check_flag(pci, val)	(pci->drvdata->flags & val)
 
@@ -1330,7 +1331,12 @@ static int imx_pcie_probe(struct platform_device *pdev)
 		imx_pcie->clks[i].id = imx_pcie->drvdata->clk_names[i];
 
 	/* Fetch clocks */
-	ret = devm_clk_bulk_get(dev, imx_pcie->drvdata->clks_cnt, imx_pcie->clks);
+	if (imx_check_flag(imx_pcie, IMX_PCIE_FLAG_CLOCKS_OPTIONAL))
+		ret = devm_clk_bulk_get_optional(dev, imx_pcie->drvdata->clks_cnt,
+						 imx_pcie->clks);
+	else
+		ret = devm_clk_bulk_get(dev, imx_pcie->drvdata->clks_cnt,
+					imx_pcie->clks);
 	if (ret)
 		return ret;
 
@@ -1480,6 +1486,8 @@ static const char * const imx8mm_clks[] = {"pcie_bus", "pcie", "pcie_aux"};
 static const char * const imx8mq_clks[] = {"pcie_bus", "pcie", "pcie_phy", "pcie_aux"};
 static const char * const imx6sx_clks[] = {"pcie_bus", "pcie", "pcie_phy", "pcie_inbound_axi"};
 static const char * const imx8q_clks[] = {"mstr", "slv", "dbi"};
+static const char * const imx95_clks[] = {"pcie_bus", "pcie", "pcie_phy", "pcie_aux", "ref"};
+static const char * const imx95_ext_osc_clks[] = {"pcie_bus", "pcie", "pcie_phy", "pcie_aux"};
 
 static const struct imx_pcie_drvdata drvdata[] = {
 	[IMX6Q] = {
@@ -1592,9 +1600,10 @@ static const struct imx_pcie_drvdata drvdata[] = {
 	},
 	[IMX95] = {
 		.variant = IMX95,
-		.flags = IMX_PCIE_FLAG_HAS_SERDES,
-		.clk_names = imx8mq_clks,
-		.clks_cnt = ARRAY_SIZE(imx8mq_clks),
+		.flags = IMX_PCIE_FLAG_HAS_SERDES |
+			 IMX_PCIE_FLAG_CLOCKS_OPTIONAL,
+		.clk_names = imx95_clks,
+		.clks_cnt = ARRAY_SIZE(imx95_clks),
 		.ltssm_off = IMX95_PE0_GEN_CTRL_3,
 		.ltssm_mask = IMX95_PCIE_LTSSM_EN,
 		.mode_off[0]  = IMX95_PE0_GEN_CTRL_1,
-- 
2.37.1
Re: [PATCH v5 02/10] PCI: imx6: Add ref clock for i.MX95 PCIe
Posted by kernel test robot 3 weeks, 3 days ago
Hi Richard,

kernel test robot noticed the following build warnings:

[auto build test WARNING on pci/next]
[also build test WARNING on pci/for-linus shawnguo/for-next mani-mhi/mhi-next linus/master v6.12-rc5 next-20241031]
[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/Richard-Zhu/dt-bindings-imx6q-pcie-Add-ref-clock-for-i-MX95-PCIe-RC/20241031-160000
base:   https://git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git next
patch link:    https://lore.kernel.org/r/20241031080655.3879139-3-hongxing.zhu%40nxp.com
patch subject: [PATCH v5 02/10] PCI: imx6: Add ref clock for i.MX95 PCIe
config: um-allmodconfig (https://download.01.org/0day-ci/archive/20241101/202411010605.6YPlxVeu-lkp@intel.com/config)
compiler: clang version 20.0.0git (https://github.com/llvm/llvm-project 639a7ac648f1e50ccd2556e17d401c04f9cce625)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241101/202411010605.6YPlxVeu-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/202411010605.6YPlxVeu-lkp@intel.com/

All warnings (new ones prefixed by >>):

   In file included from drivers/pci/controller/dwc/pci-imx6.c:21:
   In file included from include/linux/of_address.h:7:
   In file included from include/linux/io.h:14:
   In file included from arch/um/include/asm/io.h:24:
   include/asm-generic/io.h:548:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     548 |         val = __raw_readb(PCI_IOBASE + addr);
         |                           ~~~~~~~~~~ ^
   include/asm-generic/io.h:561:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     561 |         val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
         |                                                         ~~~~~~~~~~ ^
   include/uapi/linux/byteorder/little_endian.h:37:51: note: expanded from macro '__le16_to_cpu'
      37 | #define __le16_to_cpu(x) ((__force __u16)(__le16)(x))
         |                                                   ^
   In file included from drivers/pci/controller/dwc/pci-imx6.c:21:
   In file included from include/linux/of_address.h:7:
   In file included from include/linux/io.h:14:
   In file included from arch/um/include/asm/io.h:24:
   include/asm-generic/io.h:574:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     574 |         val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
         |                                                         ~~~~~~~~~~ ^
   include/uapi/linux/byteorder/little_endian.h:35:51: note: expanded from macro '__le32_to_cpu'
      35 | #define __le32_to_cpu(x) ((__force __u32)(__le32)(x))
         |                                                   ^
   In file included from drivers/pci/controller/dwc/pci-imx6.c:21:
   In file included from include/linux/of_address.h:7:
   In file included from include/linux/io.h:14:
   In file included from arch/um/include/asm/io.h:24:
   include/asm-generic/io.h:585:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     585 |         __raw_writeb(value, PCI_IOBASE + addr);
         |                             ~~~~~~~~~~ ^
   include/asm-generic/io.h:595:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     595 |         __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
         |                                                       ~~~~~~~~~~ ^
   include/asm-generic/io.h:605:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     605 |         __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
         |                                                       ~~~~~~~~~~ ^
   include/asm-generic/io.h:693:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     693 |         readsb(PCI_IOBASE + addr, buffer, count);
         |                ~~~~~~~~~~ ^
   include/asm-generic/io.h:701:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     701 |         readsw(PCI_IOBASE + addr, buffer, count);
         |                ~~~~~~~~~~ ^
   include/asm-generic/io.h:709:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     709 |         readsl(PCI_IOBASE + addr, buffer, count);
         |                ~~~~~~~~~~ ^
   include/asm-generic/io.h:718:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     718 |         writesb(PCI_IOBASE + addr, buffer, count);
         |                 ~~~~~~~~~~ ^
   include/asm-generic/io.h:727:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     727 |         writesw(PCI_IOBASE + addr, buffer, count);
         |                 ~~~~~~~~~~ ^
   include/asm-generic/io.h:736:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     736 |         writesl(PCI_IOBASE + addr, buffer, count);
         |                 ~~~~~~~~~~ ^
   In file included from drivers/pci/controller/dwc/pci-imx6.c:22:
   In file included from include/linux/pci.h:1645:
   In file included from include/linux/dmapool.h:14:
   In file included from include/linux/scatterlist.h:8:
   In file included from include/linux/mm.h:2213:
   include/linux/vmstat.h:518:36: warning: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Wenum-enum-conversion]
     518 |         return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_"
         |                               ~~~~~~~~~~~ ^ ~~~
>> drivers/pci/controller/dwc/pci-imx6.c:1490:27: warning: unused variable 'imx95_ext_osc_clks' [-Wunused-const-variable]
    1490 | static const char * const imx95_ext_osc_clks[] = {"pcie_bus", "pcie", "pcie_phy", "pcie_aux"};
         |                           ^~~~~~~~~~~~~~~~~~
   14 warnings generated.

Kconfig warnings: (for reference only)
   WARNING: unmet direct dependencies detected for MODVERSIONS
   Depends on [n]: MODULES [=y] && !COMPILE_TEST [=y]
   Selected by [y]:
   - RANDSTRUCT_FULL [=y] && (CC_HAS_RANDSTRUCT [=y] || GCC_PLUGINS [=n]) && MODULES [=y]
   WARNING: unmet direct dependencies detected for GET_FREE_REGION
   Depends on [n]: SPARSEMEM [=n]
   Selected by [m]:
   - RESOURCE_KUNIT_TEST [=m] && RUNTIME_TESTING_MENU [=y] && KUNIT [=m]


vim +/imx95_ext_osc_clks +1490 drivers/pci/controller/dwc/pci-imx6.c

  1483	
  1484	static const char * const imx6q_clks[] = {"pcie_bus", "pcie", "pcie_phy"};
  1485	static const char * const imx8mm_clks[] = {"pcie_bus", "pcie", "pcie_aux"};
  1486	static const char * const imx8mq_clks[] = {"pcie_bus", "pcie", "pcie_phy", "pcie_aux"};
  1487	static const char * const imx6sx_clks[] = {"pcie_bus", "pcie", "pcie_phy", "pcie_inbound_axi"};
  1488	static const char * const imx8q_clks[] = {"mstr", "slv", "dbi"};
  1489	static const char * const imx95_clks[] = {"pcie_bus", "pcie", "pcie_phy", "pcie_aux", "ref"};
> 1490	static const char * const imx95_ext_osc_clks[] = {"pcie_bus", "pcie", "pcie_phy", "pcie_aux"};
  1491	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Re: [PATCH v5 02/10] PCI: imx6: Add ref clock for i.MX95 PCIe
Posted by Frank Li 3 weeks, 3 days ago
On Thu, Oct 31, 2024 at 04:06:47PM +0800, Richard Zhu wrote:
> Add "ref" clock to enable reference clock. To avoid the DT
> compatibility, i.MX95 REF clock might be optional. Replace the
> devm_clk_bulk_get() by devm_clk_bulk_get_optional() to fetch
> i.MX95 PCIe clocks in driver.
>
> If use external clock, ref clock should point to external reference.
>
> If use internal clock, CREF_EN in LAST_TO_REG controls reference output,
> which implement in drivers/clk/imx/clk-imx95-blk-ctl.c.
>
> Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
> Reviewed-by: Frank Li <Frank.Li@nxp.com>
> ---
>  drivers/pci/controller/dwc/pci-imx6.c | 17 +++++++++++++----
>  1 file changed, 13 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
> index 808d1f105417..73cb69ba8933 100644
> --- a/drivers/pci/controller/dwc/pci-imx6.c
> +++ b/drivers/pci/controller/dwc/pci-imx6.c
> @@ -82,6 +82,7 @@ enum imx_pcie_variants {
>  #define IMX_PCIE_FLAG_HAS_SERDES		BIT(6)
>  #define IMX_PCIE_FLAG_SUPPORT_64BIT		BIT(7)
>  #define IMX_PCIE_FLAG_CPU_ADDR_FIXUP		BIT(8)
> +#define IMX_PCIE_FLAG_CLOCKS_OPTIONAL		BIT(9)
>
>  #define imx_check_flag(pci, val)	(pci->drvdata->flags & val)
>
> @@ -1330,7 +1331,12 @@ static int imx_pcie_probe(struct platform_device *pdev)
>  		imx_pcie->clks[i].id = imx_pcie->drvdata->clk_names[i];
>
>  	/* Fetch clocks */
> -	ret = devm_clk_bulk_get(dev, imx_pcie->drvdata->clks_cnt, imx_pcie->clks);
> +	if (imx_check_flag(imx_pcie, IMX_PCIE_FLAG_CLOCKS_OPTIONAL))
> +		ret = devm_clk_bulk_get_optional(dev, imx_pcie->drvdata->clks_cnt,
> +						 imx_pcie->clks);
> +	else
> +		ret = devm_clk_bulk_get(dev, imx_pcie->drvdata->clks_cnt,
> +					imx_pcie->clks);

int require_cnt = imx_pcie->drvdata->clks_cnt - imx_pcie->drvdata->clks_optional_cnt;
devm_clk_bulk_get(dev, require_cnt, imx_pcie->clks);
devm_clk_bulk_get_optional(dev, imx_pcie->drvdata->clks_optional_cnt,
			imx_pcie->clks + require_cnt);

So we easy to add more optional clks in future and without lost required
clocks safty checks.

>  	if (ret)
>  		return ret;
>
> @@ -1480,6 +1486,8 @@ static const char * const imx8mm_clks[] = {"pcie_bus", "pcie", "pcie_aux"};
>  static const char * const imx8mq_clks[] = {"pcie_bus", "pcie", "pcie_phy", "pcie_aux"};
>  static const char * const imx6sx_clks[] = {"pcie_bus", "pcie", "pcie_phy", "pcie_inbound_axi"};
>  static const char * const imx8q_clks[] = {"mstr", "slv", "dbi"};
> +static const char * const imx95_clks[] = {"pcie_bus", "pcie", "pcie_phy", "pcie_aux", "ref"};
> +static const char * const imx95_ext_osc_clks[] = {"pcie_bus", "pcie", "pcie_phy", "pcie_aux"};
>
>  static const struct imx_pcie_drvdata drvdata[] = {
>  	[IMX6Q] = {
> @@ -1592,9 +1600,10 @@ static const struct imx_pcie_drvdata drvdata[] = {
>  	},
>  	[IMX95] = {
>  		.variant = IMX95,
> -		.flags = IMX_PCIE_FLAG_HAS_SERDES,
> -		.clk_names = imx8mq_clks,
> -		.clks_cnt = ARRAY_SIZE(imx8mq_clks),
> +		.flags = IMX_PCIE_FLAG_HAS_SERDES |
> +			 IMX_PCIE_FLAG_CLOCKS_OPTIONAL,
> +		.clk_names = imx95_clks,
> +		.clks_cnt = ARRAY_SIZE(imx95_clks),

Suggest add .clks_optional_cnt = 1,

>  		.ltssm_off = IMX95_PE0_GEN_CTRL_3,
>  		.ltssm_mask = IMX95_PCIE_LTSSM_EN,
>  		.mode_off[0]  = IMX95_PE0_GEN_CTRL_1,
> --
> 2.37.1
>