[PATCH] cpufreq: ti-cpufreq: Introduce quirks to handle syscon fails appropriately
From: Nishanth Menon <nm@ti.com>
Date: 2024-08-28 13:19:35
Also in:
linux-omap, linux-pm, lkml
Subsystem:
cpu frequency scaling framework, the rest · Maintainers:
"Rafael J. Wysocki", Viresh Kumar, Linus Torvalds
Commit b4bc9f9e27ed ("cpufreq: ti-cpufreq: add support for omap34xx
and omap36xx") introduced special handling for OMAP3 class devices
where syscon node may not be present. However, this also creates a bug
where the syscon node is present, however the offset used to read
is beyond the syscon defined range.
Fix this by providing a quirk option that is populated when such
special handling is required. This allows proper failure for all other
platforms when the syscon node and efuse offsets are mismatched.
Fixes: b4bc9f9e27ed ("cpufreq: ti-cpufreq: add support for omap34xx and omap36xx")
Signed-off-by: Nishanth Menon <nm@ti.com>
---
NOTE: this combined with https://lore.kernel.org/r/20240828121008.3066002-1-nm@ti.com (local)
has created a bunch of un-intended bugs on other TI SoCs such
as seen in https://lore.kernel.org/all/20240826-opp-v3-1-0934f8309e13@ti.com/ (local)
https://lore.kernel.org/all/20240827131342.6wrielete3yeoinl@bryanbrattlof.com/ (local)
etc.
drivers/cpufreq/ti-cpufreq.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/cpufreq/ti-cpufreq.c b/drivers/cpufreq/ti-cpufreq.c
index 220fff7a302e..804329e81eb8 100644
--- a/drivers/cpufreq/ti-cpufreq.c
+++ b/drivers/cpufreq/ti-cpufreq.c@@ -90,6 +90,9 @@ struct ti_cpufreq_soc_data { unsigned long efuse_shift; unsigned long rev_offset; bool multi_regulator; +/* Backward compatibility hack: Might have missing syscon */ +#define TI_QUIRK_SYSCON_MAY_BE_MISSING 0x1 + u8 quirks; }; struct ti_cpufreq_data {
@@ -254,6 +257,7 @@ static struct ti_cpufreq_soc_data omap34xx_soc_data = { .efuse_mask = BIT(3), .rev_offset = OMAP3_CONTROL_IDCODE - OMAP3_SYSCON_BASE, .multi_regulator = false, + .quirks = TI_QUIRK_SYSCON_MAY_BE_MISSING, }; /*
@@ -281,6 +285,7 @@ static struct ti_cpufreq_soc_data omap36xx_soc_data = { .efuse_mask = BIT(9), .rev_offset = OMAP3_CONTROL_IDCODE - OMAP3_SYSCON_BASE, .multi_regulator = true, + .quirks = TI_QUIRK_SYSCON_MAY_BE_MISSING, }; /*
@@ -295,6 +300,7 @@ static struct ti_cpufreq_soc_data am3517_soc_data = { .efuse_mask = 0, .rev_offset = OMAP3_CONTROL_IDCODE - OMAP3_SYSCON_BASE, .multi_regulator = false, + .quirks = TI_QUIRK_SYSCON_MAY_BE_MISSING, }; static struct ti_cpufreq_soc_data am625_soc_data = {
@@ -340,7 +346,7 @@ static int ti_cpufreq_get_efuse(struct ti_cpufreq_data *opp_data, ret = regmap_read(opp_data->syscon, opp_data->soc_data->efuse_offset, &efuse); - if (ret == -EIO) { + if (opp_data->soc_data->quirks & TI_QUIRK_SYSCON_MAY_BE_MISSING && ret == -EIO) { /* not a syscon register! */ void __iomem *regs = ioremap(OMAP3_SYSCON_BASE + opp_data->soc_data->efuse_offset, 4);
@@ -381,7 +387,7 @@ static int ti_cpufreq_get_rev(struct ti_cpufreq_data *opp_data, ret = regmap_read(opp_data->syscon, opp_data->soc_data->rev_offset, &revision); - if (ret == -EIO) { + if (opp_data->soc_data->quirks & TI_QUIRK_SYSCON_MAY_BE_MISSING && ret == -EIO) { /* not a syscon register! */ void __iomem *regs = ioremap(OMAP3_SYSCON_BASE + opp_data->soc_data->rev_offset, 4);
--
2.43.0