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

[Alexandru Ardelean <alexandru.ardelean@analog.com>]

From: Mircea Caprioru <mircea.caprioru@analog.com>

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@analog.com>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
---
 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)) {
+			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);
-- 
2.17.1