Re: [PATCH 2/2] clk: axi-clkgen: Add support for FPGA info

From: Tom Rix
Date: Thu Feb 11 2021 - 10:19:44 EST



On 2/10/21 2:15 AM, Alexandru Ardelean wrote:
> From: Mircea Caprioru <mircea.caprioru@xxxxxxxxxx>
>
> This patch adds support for vco maximum and minimum ranges in accordance
> with fpga speed grade, voltage, device package, technology and family. This
> new information is extracted from two new registers implemented in the ip
> core: ADI_REG_FPGA_INFO and ADI_REG_FPGA_VOLTAGE, which are stored in the
> 'include/linux/fpga/adi-axi-common.h' file as they are common to all ADI
> FPGA cores.
>
> Signed-off-by: Mircea Caprioru <mircea.caprioru@xxxxxxxxxx>
> Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
> ---
> drivers/clk/clk-axi-clkgen.c | 52 +++++++++++++++++++++++++++++++++++-
> 1 file changed, 51 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/clk/clk-axi-clkgen.c b/drivers/clk/clk-axi-clkgen.c
> index ac6ff736ac8f..e4d6c87f8a07 100644
> --- a/drivers/clk/clk-axi-clkgen.c
> +++ b/drivers/clk/clk-axi-clkgen.c
> @@ -8,6 +8,7 @@
>
> #include <linux/platform_device.h>
> #include <linux/clk-provider.h>
> +#include <linux/fpga/adi-axi-common.h>
> #include <linux/slab.h>
> #include <linux/io.h>
> #include <linux/of.h>
> @@ -240,6 +241,50 @@ static void axi_clkgen_read(struct axi_clkgen *axi_clkgen,
> *val = readl(axi_clkgen->base + reg);
> }
>
> +static void axi_clkgen_setup_ranges(struct axi_clkgen *axi_clkgen)
> +{
> + struct axi_clkgen_limits *limits = &axi_clkgen->limits;
> + unsigned int reg_value;
> + unsigned int tech, family, speed_grade, voltage;
> +
> + axi_clkgen_read(axi_clkgen, ADI_AXI_REG_FPGA_INFO, &reg_value);
> + tech = ADI_AXI_INFO_FPGA_TECH(reg_value);
> + family = ADI_AXI_INFO_FPGA_FAMILY(reg_value);
> + speed_grade = ADI_AXI_INFO_FPGA_SPEED_GRADE(reg_value);
> +
> + axi_clkgen_read(axi_clkgen, ADI_AXI_REG_FPGA_VOLTAGE, &reg_value);
> + voltage = ADI_AXI_INFO_FPGA_VOLTAGE(reg_value);
> +
> + switch (speed_grade) {
> + case ADI_AXI_FPGA_SPEED_GRADE_XILINX_1 ... ADI_AXI_FPGA_SPEED_GRADE_XILINX_1LV:
> + limits->fvco_max = 1200000;
> + limits->fpfd_max = 450000;
> + break;
> + case ADI_AXI_FPGA_SPEED_GRADE_XILINX_2 ... ADI_AXI_FPGA_SPEED_GRADE_XILINX_2LV:
> + limits->fvco_max = 1440000;
> + limits->fpfd_max = 500000;
> + if ((family == ADI_AXI_FPGA_FAMILY_XILINX_KINTEX) |
> + (family == ADI_AXI_FPGA_FAMILY_XILINX_ARTIX)) {
NOTE: If any of the errors are false positives, please report
      them to the maintainer, see CHECKPATCH in MAINTAINERS.
3a419c9317b157ef06ca347b7e6bbab846a3d605 clk: axi-clkgen: Add support for FPGA info
CHECK: Unnecessary parentheses around 'family == ADI_AXI_FPGA_FAMILY_XILINX_KINTEX'
#57: FILE: drivers/clk/clk-axi-clkgen.c:266:
+        if ((family == ADI_AXI_FPGA_FAMILY_XILINX_KINTEX) |
+            (family == ADI_AXI_FPGA_FAMILY_XILINX_ARTIX)) {

Please use checkpatch -strict to find this problem.

Likely the '|', should be '||'

Tom

> + if (voltage < 950) {
> + limits->fvco_max = 1200000;
> + limits->fpfd_max = 450000;
> + }
> + }
> + break;
> + case ADI_AXI_FPGA_SPEED_GRADE_XILINX_3:
> + limits->fvco_max = 1600000;
> + limits->fpfd_max = 550000;
> + break;
> + default:
> + break;
> + };
> +
> + if (tech == ADI_AXI_FPGA_TECH_XILINX_ULTRASCALE_PLUS) {
> + limits->fvco_max = 1600000;
> + limits->fvco_min = 800000;
> + }
> +}
> +
> static int axi_clkgen_wait_non_busy(struct axi_clkgen *axi_clkgen)
> {
> unsigned int timeout = 10000;
> @@ -510,7 +555,7 @@ static int axi_clkgen_probe(struct platform_device *pdev)
> struct clk_init_data init;
> const char *parent_names[2];
> const char *clk_name;
> - unsigned int i;
> + unsigned int i, ver;
> int ret;
>
> dflt_limits = device_get_match_data(&pdev->dev);
> @@ -537,6 +582,11 @@ static int axi_clkgen_probe(struct platform_device *pdev)
>
> memcpy(&axi_clkgen->limits, dflt_limits, sizeof(axi_clkgen->limits));
>
> + axi_clkgen_read(axi_clkgen, ADI_AXI_REG_VERSION, &ver);
> +
> + if (ADI_AXI_PCORE_VER_MAJOR(ver) > 0x04)
> + axi_clkgen_setup_ranges(axi_clkgen);
> +
> clk_name = pdev->dev.of_node->name;
> of_property_read_string(pdev->dev.of_node, "clock-output-names",
> &clk_name);