[PATCH v4 1/1] cpufreq: ti: Add EPROBE_DEFER for K3 SoCs

[Akashdeep Kaur]

On K3 SoCs, ti-cpufreq relies on k3-socinfo to register the SoC
device before soc_device_match() can return valid revision
information. If ti-cpufreq probes before k3-socinfo,
soc_device_match() returns NULL, leading to incorrect CPU frequency
scaling behavior.
Defer probe when k3-socinfo hasn't registered the SoC device yet.

Signed-off-by: Akashdeep Kaur <a-kaur@xxxxxx>
---
 drivers/cpufreq/ti-cpufreq.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/cpufreq/ti-cpufreq.c b/drivers/cpufreq/ti-cpufreq.c
index a01abc1622eb..8219751da175 100644
--- a/drivers/cpufreq/ti-cpufreq.c
+++ b/drivers/cpufreq/ti-cpufreq.c
@@ -99,6 +99,7 @@ struct ti_cpufreq_soc_data {
 	unsigned long efuse_shift;
 	unsigned long rev_offset;
 	bool multi_regulator;
+	bool needs_k3_socinfo;
 /* Backward compatibility hack: Might have missing syscon */
 #define TI_QUIRK_SYSCON_MAY_BE_MISSING	0x1
 /* Backward compatibility hack: new syscon size is 1 register wide */
@@ -347,6 +348,7 @@ static struct ti_cpufreq_soc_data am625_soc_data = {
 	.efuse_mask = 0x07c0,
 	.efuse_shift = 0x6,
 	.multi_regulator = false,
+	.needs_k3_socinfo = true,
 	.quirks = TI_QUIRK_SYSCON_IS_SINGLE_REG,
 };
 
@@ -356,6 +358,7 @@ static struct ti_cpufreq_soc_data am62a7_soc_data = {
 	.efuse_mask = 0x07c0,
 	.efuse_shift = 0x6,
 	.multi_regulator = false,
+	.needs_k3_socinfo = true,
 };
 
 static struct ti_cpufreq_soc_data am62l3_soc_data = {
@@ -364,6 +367,7 @@ static struct ti_cpufreq_soc_data am62l3_soc_data = {
 	.efuse_mask = 0x07c0,
 	.efuse_shift = 0x6,
 	.multi_regulator = false,
+	.needs_k3_socinfo = true,
 };
 
 static struct ti_cpufreq_soc_data am62p5_soc_data = {
@@ -372,6 +376,7 @@ static struct ti_cpufreq_soc_data am62p5_soc_data = {
 	.efuse_mask = 0x07c0,
 	.efuse_shift = 0x6,
 	.multi_regulator = false,
+	.needs_k3_socinfo = true,
 };
 
 /**
@@ -443,6 +448,12 @@ static int ti_cpufreq_get_rev(struct ti_cpufreq_data *opp_data,
 		goto done;
 	}

+	/* Defer if k3-socinfo hasn't registered the SoC device yet */
+	if (opp_data->soc_data->needs_k3_socinfo) {
+		dev_dbg(opp_data->cpu_dev,
+			"SoC info not ready yet, deferring probe\n");
+		return -EPROBE_DEFER;
+	}
+
 	ret = regmap_read(opp_data->syscon, opp_data->soc_data->rev_offset,
 			  &revision);
 	if (opp_data->soc_data->quirks & TI_QUIRK_SYSCON_MAY_BE_MISSING && ret == -EIO) {
-- 
2.34.1