openwrt/target/linux/bcm27xx/patches-5.4/950-0216-clk-bcm2835-Add-support-for-setting-leaf-clock-rates.patch
Hauke Mehrtens c6ddf8d502 kernel: bump 5.4 to 5.4.179
Many changes were done in drivers/pinctrl/bcm/pinctrl-bcm2835.c between
5.4.171 and 5.4.179.
The following 3 patches do not apply any more:
* target/linux/bcm27xx/patches-5.4/950-0316-pinctrl-bcm2835-Add-support-for-BCM2711-pull-up-func.patch
  This was already integrated in kernel v5.4-rc1, it was never needed.

* target/linux/bcm27xx/patches-5.4/950-0328-Revert-pinctrl-bcm2835-Pass-irqchip-when-adding-gpio.patch
* target/linux/bcm27xx/patches-5.4/950-0362-pinctrl-bcm2835-Change-init-order-for-gpio-hogs.patch
I think these were done to fix the problem which was really fixed in
commit 75278f1aff5e ("pinctrl: bcm2835: Change init order for gpio
hogs") from v5.4.175

target/linux/generic/backport-5.4/716-v5.5-net-sfp-move-fwnode-parsing-into-sfp-bus-layer.patch
Move fwnode_device_is_available to the same position as in kernel 5.10.

target/linux/layerscape/patches-5.4/302-dts-0083-arm64-ls1028a-qds-correct-bus-of-rtc.patch
Applied in commit 65816c1034769e714edb70f59a33bc5472d9e55f ("arm64: dts:
ls1028a-qds: move rtc node to the correct i2c bus")

Compile-tested: lantiq/xrx200, bcm27xx/bcm2710
Run-tested: lantiq/xrx200

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
2022-02-12 19:41:39 +01:00

54 lines
1.8 KiB
Diff

From cfe0832e8306cd9955f682b7314a5a6fc3b9d514 Mon Sep 17 00:00:00 2001
From: Eric Anholt <eric@anholt.net>
Date: Thu, 2 May 2019 15:11:05 -0700
Subject: [PATCH] clk: bcm2835: Add support for setting leaf clock
rates while running.
As long as you wait for !BUSY, you can do glitch-free updates of clock
rate while the clock is running.
Signed-off-by: Eric Anholt <eric@anholt.net>
---
drivers/clk/bcm/clk-bcm2835.c | 22 +++++++++++++---------
1 file changed, 13 insertions(+), 9 deletions(-)
--- a/drivers/clk/bcm/clk-bcm2835.c
+++ b/drivers/clk/bcm/clk-bcm2835.c
@@ -1109,15 +1109,19 @@ static int bcm2835_clock_set_rate(struct
spin_lock(&cprman->regs_lock);
- /*
- * Setting up frac support
- *
- * In principle it is recommended to stop/start the clock first,
- * but as we set CLK_SET_RATE_GATE during registration of the
- * clock this requirement should be take care of by the
- * clk-framework.
+ ctl = cprman_read(cprman, data->ctl_reg);
+
+ /* If the clock is running, we have to pause clock generation while
+ * updating the control and div regs. This is glitchless (no clock
+ * signals generated faster than the rate) but each reg access is two
+ * OSC cycles so the clock will slow down for a moment.
*/
- ctl = cprman_read(cprman, data->ctl_reg) & ~CM_FRAC;
+ if (ctl & CM_ENABLE) {
+ cprman_write(cprman, data->ctl_reg, ctl & ~CM_ENABLE);
+ bcm2835_clock_wait_busy(clock);
+ }
+
+ ctl &= ~CM_FRAC;
ctl |= (div & CM_DIV_FRAC_MASK) ? CM_FRAC : 0;
cprman_write(cprman, data->ctl_reg, ctl);
@@ -1489,7 +1493,7 @@ static struct clk_hw *bcm2835_register_c
init.ops = &bcm2835_vpu_clock_clk_ops;
} else {
init.ops = &bcm2835_clock_clk_ops;
- init.flags |= CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE;
+ init.flags |= CLK_SET_PARENT_GATE;
/* If the clock wasn't actually enabled at boot, it's not
* critical.