Booting v6.8 results in a hang on various IPQ5018 based boards.
Investigating the problem showed that the hang happens when the
clk_alpha_pll_stromer_plus_set_rate() function tries to write
into the PLL_MODE register of the APSS PLL.
Checking the downstream code revealed that it uses [1] stromer
specific operations for IPQ5018, whereas in the current code
the stromer plus specific operations are used.
The ops in the 'ipq_pll_stromer_plus' clock definition can't be
changed since that is needed for IPQ5332, so add a new alpha pll
clock declaration which uses the correct stromer ops and use this
new clock for IPQ5018 to avoid the boot failure.
Also, change pll_type in 'ipq5018_pll_data' to
CLK_ALPHA_PLL_TYPE_STROMER to better reflect that it is a Stromer
PLL and change the apss_ipq_pll_probe() function accordingly.
1. https://git.codelinaro.org/clo/qsdk/oss/kernel/linux-ipq-5.4/-/blob/NHSS.QSDK.12.4/drivers/clk/qcom/apss-ipq5018.c#L67
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 50492f929486 ("clk: qcom: apss-ipq-pll: add support for IPQ5018")
Signed-off-by: Gabor Juhos <j4g8y7@xxxxxxxxx>
---
Changes in v2:
- extend commit description due to the changes
- add a comment about why CLK_ALPHA_PLL_TYPE_STROMER_PLUS register offsets
are used
- constify hw clock init data (Stephen)
- change pll_type in ipq5018_pll_data to CLK_ALPHA_PLL_TYPE_STROMER (Konrad)
- Link to v1: https://lore.kernel.org/r/20240311-apss-ipq-pll-ipq5018-hang-v1-1-8ed42b7a904d@xxxxxxxxx
---
Based on v6.8.
---
drivers/clk/qcom/apss-ipq-pll.c | 30 +++++++++++++++++++++++++++---
1 file changed, 27 insertions(+), 3 deletions(-)
diff --git a/drivers/clk/qcom/apss-ipq-pll.c b/drivers/clk/qcom/apss-ipq-pll.c
index 678b805f13d45..dfffec2f06ae7 100644
--- a/drivers/clk/qcom/apss-ipq-pll.c
+++ b/drivers/clk/qcom/apss-ipq-pll.c
@@ -55,6 +55,29 @@ static struct clk_alpha_pll ipq_pll_huayra = {
},
};
+static struct clk_alpha_pll ipq_pll_stromer = {
+ .offset = 0x0,
+ /*
+ * Reuse CLK_ALPHA_PLL_TYPE_STROMER_PLUS register offsets.
+ * Although this is a bit confusing, but the offset values
+ * are correct nevertheless.
+ */
+ .regs = ipq_pll_offsets[CLK_ALPHA_PLL_TYPE_STROMER_PLUS],
+ .flags = SUPPORTS_DYNAMIC_UPDATE,
+ .clkr = {
+ .enable_reg = 0x0,
+ .enable_mask = BIT(0),
+ .hw.init = &(const struct clk_init_data) {
+ .name = "a53pll",
+ .parent_data = &(const struct clk_parent_data) {
+ .fw_name = "xo",
+ },
+ .num_parents = 1,
+ .ops = &clk_alpha_pll_stromer_ops,
+ },
+ },
+};
+
static struct clk_alpha_pll ipq_pll_stromer_plus = {
.offset = 0x0,
.regs = ipq_pll_offsets[CLK_ALPHA_PLL_TYPE_STROMER_PLUS],
@@ -144,8 +167,8 @@ struct apss_pll_data {
};
static const struct apss_pll_data ipq5018_pll_data = {
- .pll_type = CLK_ALPHA_PLL_TYPE_STROMER_PLUS,
- .pll = &ipq_pll_stromer_plus,
+ .pll_type = CLK_ALPHA_PLL_TYPE_STROMER,
+ .pll = &ipq_pll_stromer,
.pll_config = &ipq5018_pll_config,
};
@@ -203,7 +226,8 @@ static int apss_ipq_pll_probe(struct platform_device *pdev)
if (data->pll_type == CLK_ALPHA_PLL_TYPE_HUAYRA)
clk_alpha_pll_configure(data->pll, regmap, data->pll_config);
- else if (data->pll_type == CLK_ALPHA_PLL_TYPE_STROMER_PLUS)
+ else if (data->pll_type == CLK_ALPHA_PLL_TYPE_STROMER ||
+ data->pll_type == CLK_ALPHA_PLL_TYPE_STROMER_PLUS)
clk_stromer_pll_configure(data->pll, regmap, data->pll_config);
ret = devm_clk_register_regmap(dev, &data->pll->clkr);
---
base-commit: e8f897f4afef0031fe618a8e94127a0934896aba
change-id: 20240311-apss-ipq-pll-ipq5018-hang-74d9a8f47136
Best regards,