A collection of other clock fixes in -next for the RPi

This commit is contained in:
Peter Robinson 2016-10-24 22:12:58 +01:00
parent bb4f705986
commit 08645910f6
2 changed files with 266 additions and 2 deletions

View File

@ -682,3 +682,266 @@ index b68bf57..8c7763f 100644
--
cgit v0.12
From e69fdcca836f0b81a2260b69429c8622a80ea891 Mon Sep 17 00:00:00 2001
From: Eric Anholt <eric@anholt.net>
Date: Wed, 1 Jun 2016 12:05:33 -0700
Subject: clk: bcm2835: Mark the VPU clock as critical
The VPU clock is also the clock for our AXI bus, so we really can't
disable it. This might have happened during boot if, for example,
uart1 (aux_uart clock) probed and was then disabled before the other
consumers of the VPU clock had probed.
Signed-off-by: Eric Anholt <eric@anholt.net>
Acked-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
---
drivers/clk/bcm/clk-bcm2835.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/clk/bcm/clk-bcm2835.c b/drivers/clk/bcm/clk-bcm2835.c
index 7a79708..d9db03c 100644
--- a/drivers/clk/bcm/clk-bcm2835.c
+++ b/drivers/clk/bcm/clk-bcm2835.c
@@ -443,6 +443,8 @@ struct bcm2835_clock_data {
/* Number of fractional bits in the divider */
u32 frac_bits;
+ u32 flags;
+
bool is_vpu_clock;
bool is_mash_clock;
};
@@ -1230,7 +1232,7 @@ static struct clk *bcm2835_register_clock(struct bcm2835_cprman *cprman,
init.parent_names = parents;
init.num_parents = data->num_mux_parents;
init.name = data->name;
- init.flags = CLK_IGNORE_UNUSED;
+ init.flags = data->flags | CLK_IGNORE_UNUSED;
if (data->is_vpu_clock) {
init.ops = &bcm2835_vpu_clock_clk_ops;
@@ -1649,6 +1651,7 @@ static const struct bcm2835_clk_desc clk_desc_array[] = {
.div_reg = CM_VPUDIV,
.int_bits = 12,
.frac_bits = 8,
+ .flags = CLK_IS_CRITICAL,
.is_vpu_clock = true),
/* clocks with per parent mux */
--
cgit v0.12
From eddcbe8398fc7103fccd22aa6df6917caf0123bf Mon Sep 17 00:00:00 2001
From: Eric Anholt <eric@anholt.net>
Date: Wed, 1 Jun 2016 12:05:34 -0700
Subject: clk: bcm2835: Mark GPIO clocks enabled at boot as critical
These divide off of PLLD_PER and are used for the ethernet and wifi
PHYs source PLLs. Neither of them is currently represented by a phy
device that would grab the clock for us.
This keeps other drivers from killing the networking PHYs when they
disable their own clocks and trigger PLLD_PER's refcount going to 0.
Signed-off-by: Eric Anholt <eric@anholt.net>
Acked-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
---
drivers/clk/bcm/clk-bcm2835.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/drivers/clk/bcm/clk-bcm2835.c b/drivers/clk/bcm/clk-bcm2835.c
index d9db03c..400615b 100644
--- a/drivers/clk/bcm/clk-bcm2835.c
+++ b/drivers/clk/bcm/clk-bcm2835.c
@@ -1239,6 +1239,12 @@ static struct clk *bcm2835_register_clock(struct bcm2835_cprman *cprman,
} else {
init.ops = &bcm2835_clock_clk_ops;
init.flags |= CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE;
+
+ /* If the clock wasn't actually enabled at boot, it's not
+ * critical.
+ */
+ if (!(cprman_read(cprman, data->ctl_reg) & CM_ENABLE))
+ init.flags &= ~CLK_IS_CRITICAL;
}
clock = devm_kzalloc(cprman->dev, sizeof(*clock), GFP_KERNEL);
@@ -1708,13 +1714,15 @@ static const struct bcm2835_clk_desc clk_desc_array[] = {
.div_reg = CM_GP1DIV,
.int_bits = 12,
.frac_bits = 12,
+ .flags = CLK_IS_CRITICAL,
.is_mash_clock = true),
[BCM2835_CLOCK_GP2] = REGISTER_PER_CLK(
.name = "gp2",
.ctl_reg = CM_GP2CTL,
.div_reg = CM_GP2DIV,
.int_bits = 12,
- .frac_bits = 12),
+ .frac_bits = 12,
+ .flags = CLK_IS_CRITICAL),
/* HDMI state machine */
[BCM2835_CLOCK_HSM] = REGISTER_PER_CLK(
--
cgit v0.12
From 9e400c5cc5c105e35216ac59a346f20cdd7613be Mon Sep 17 00:00:00 2001
From: Eric Anholt <eric@anholt.net>
Date: Wed, 1 Jun 2016 12:05:35 -0700
Subject: clk: bcm2835: Mark the CM SDRAM clock's parent as critical
While the SDRAM is being driven by its dedicated PLL most of the time,
there is a little loop running in the firmware that periodically turns
on the CM SDRAM clock (using its pre-initialized parent) and switches
SDRAM to using the CM clock to do PVT recalibration.
This avoids system hangs if we choose SDRAM's parent for some other
clock, then disable that clock.
Signed-off-by: Eric Anholt <eric@anholt.net>
Acked-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
---
drivers/clk/bcm/clk-bcm2835.c | 25 +++++++++++++++++++++++++
1 file changed, 25 insertions(+)
diff --git a/drivers/clk/bcm/clk-bcm2835.c b/drivers/clk/bcm/clk-bcm2835.c
index 400615b..c6420b3 100644
--- a/drivers/clk/bcm/clk-bcm2835.c
+++ b/drivers/clk/bcm/clk-bcm2835.c
@@ -36,6 +36,7 @@
#include <linux/clk-provider.h>
#include <linux/clkdev.h>
+#include <linux/clk.h>
#include <linux/clk/bcm2835.h>
#include <linux/debugfs.h>
#include <linux/module.h>
@@ -1801,6 +1802,25 @@ static const struct bcm2835_clk_desc clk_desc_array[] = {
.ctl_reg = CM_PERIICTL),
};
+/*
+ * Permanently take a reference on the parent of the SDRAM clock.
+ *
+ * While the SDRAM is being driven by its dedicated PLL most of the
+ * time, there is a little loop running in the firmware that
+ * periodically switches the SDRAM to using our CM clock to do PVT
+ * recalibration, with the assumption that the previously configured
+ * SDRAM parent is still enabled and running.
+ */
+static int bcm2835_mark_sdc_parent_critical(struct clk *sdc)
+{
+ struct clk *parent = clk_get_parent(sdc);
+
+ if (IS_ERR(parent))
+ return PTR_ERR(parent);
+
+ return clk_prepare_enable(parent);
+}
+
static int bcm2835_clk_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
@@ -1810,6 +1830,7 @@ static int bcm2835_clk_probe(struct platform_device *pdev)
const struct bcm2835_clk_desc *desc;
const size_t asize = ARRAY_SIZE(clk_desc_array);
size_t i;
+ int ret;
cprman = devm_kzalloc(dev,
sizeof(*cprman) + asize * sizeof(*clks),
@@ -1840,6 +1861,10 @@ static int bcm2835_clk_probe(struct platform_device *pdev)
clks[i] = desc->clk_register(cprman, desc->data);
}
+ ret = bcm2835_mark_sdc_parent_critical(clks[BCM2835_CLOCK_SDRAM]);
+ if (ret)
+ return ret;
+
return of_clk_add_provider(dev->of_node, of_clk_src_onecell_get,
&cprman->onecell);
}
--
cgit v0.12
From 67615c588a059b731df9d019edc3c561d8006ec9 Mon Sep 17 00:00:00 2001
From: Eric Anholt <eric@anholt.net>
Date: Wed, 1 Jun 2016 12:05:36 -0700
Subject: clk: bcm2835: Skip PLLC clocks when deciding on a new clock parent
If the firmware had set up a clock to source from PLLC, go along with
it. But if we're looking for a new parent, we don't want to switch it
to PLLC because the firmware will force PLLC (and thus the AXI bus
clock) to different frequencies during over-temp/under-voltage,
without notification to Linux.
On my system, this moves the Linux-enabled HDMI state machine and DSI1
escape clock over to plld_per from pllc_per. EMMC still ends up on
pllc_per, because the firmware had set it up to use that.
Signed-off-by: Eric Anholt <eric@anholt.net>
Fixes: 41691b8862e2 ("clk: bcm2835: Add support for programming the audio domain clocks")
Acked-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
---
drivers/clk/bcm/clk-bcm2835.c | 23 +++++++++++++++++++++++
1 file changed, 23 insertions(+)
diff --git a/drivers/clk/bcm/clk-bcm2835.c b/drivers/clk/bcm/clk-bcm2835.c
index c6420b3..e8a9646a 100644
--- a/drivers/clk/bcm/clk-bcm2835.c
+++ b/drivers/clk/bcm/clk-bcm2835.c
@@ -1009,16 +1009,28 @@ static int bcm2835_clock_set_rate(struct clk_hw *hw,
return 0;
}
+static bool
+bcm2835_clk_is_pllc(struct clk_hw *hw)
+{
+ if (!hw)
+ return false;
+
+ return strncmp(clk_hw_get_name(hw), "pllc", 4) == 0;
+}
+
static int bcm2835_clock_determine_rate(struct clk_hw *hw,
struct clk_rate_request *req)
{
struct bcm2835_clock *clock = bcm2835_clock_from_hw(hw);
struct clk_hw *parent, *best_parent = NULL;
+ bool current_parent_is_pllc;
unsigned long rate, best_rate = 0;
unsigned long prate, best_prate = 0;
size_t i;
u32 div;
+ current_parent_is_pllc = bcm2835_clk_is_pllc(clk_hw_get_parent(hw));
+
/*
* Select parent clock that results in the closest but lower rate
*/
@@ -1026,6 +1038,17 @@ static int bcm2835_clock_determine_rate(struct clk_hw *hw,
parent = clk_hw_get_parent_by_index(hw, i);
if (!parent)
continue;
+
+ /*
+ * Don't choose a PLLC-derived clock as our parent
+ * unless it had been manually set that way. PLLC's
+ * frequency gets adjusted by the firmware due to
+ * over-temp or under-voltage conditions, without
+ * prior notification to our clock consumer.
+ */
+ if (bcm2835_clk_is_pllc(parent) && !current_parent_is_pllc)
+ continue;
+
prate = clk_hw_get_rate(parent);
div = bcm2835_clock_choose_div(hw, req->rate, prate, true);
rate = bcm2835_clock_rate_from_divisor(clock, prate, div);
--
cgit v0.12

View File

@ -42,7 +42,7 @@ Summary: The Linux kernel
# For non-released -rc kernels, this will be appended after the rcX and
# gitX tags, so a 3 here would become part of release "0.rcX.gitX.3"
#
%global baserelease 300
%global baserelease 301
%global fedora_build %{baserelease}
# base_sublevel is the kernel version we're starting with and patching
@ -2161,8 +2161,9 @@ fi
#
#
%changelog
* Mon Oct 24 2016 Peter Robinson <pbrobinson@fedoraproject.org>
* Mon Oct 24 2016 Peter Robinson <pbrobinson@fedoraproject.org> 4.8.4-301
- Upstream fix for Raspberry Pi to fix setting low-resolution video modes on HDMI
- A collection of other clock fixes in -next for the RPi
* Mon Oct 24 2016 Justin M. Forbes <jforbes@fedoraproject.org> - 4.8.4-300
- Linux v4.8.4