bcm27xx: add support for linux v5.15

Build system: x86_64
Build-tested: bcm2708, bcm2709, bcm2710, bcm2711
Run-tested: bcm2708/RPiB+, bcm2709/RPi3B, bcm2710/RPi3B, bcm2711/RPi4B

Signed-off-by: Marty Jones <mj8263788@gmail.com>
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>

1 files changed, 73 insertions, 0 deletions

diff --git a/target/linux/bcm27xx/patches-5.15/950-0850-clk-Introduce-clk_hw_init_rate_request.patch b/target/linux/bcm27xx/patches-5.15/950-0850-clk-Introduce-clk_hw_init_rate_request.patch
new file mode 100644
index 0000000000..6a04498301
--- /dev/null
+++ b/target/linux/bcm27xx/patches-5.15/950-0850-clk-Introduce-clk_hw_init_rate_request.patch
@@ -0,0 +1,73 @@
+From 7023dd1743aa6bb305fdce96e6e80eecc6e01f16 Mon Sep 17 00:00:00 2001
+From: Maxime Ripard <maxime@cerno.tech>
+Date: Sat, 2 Apr 2022 14:49:56 +0200
+Subject: [PATCH] clk: Introduce clk_hw_init_rate_request()
+
+Some drivers (at91, imx, qcom) use __clk_determine_rate directly, and
+thus will need to initialise a clk_rate_request structure.
+
+However, drivers don't have access to the function that the core uses to
+initialize that structure which could prove to be useful.
+
+Let's create a function for clock providers that will initialize a
+clk_rate_request for a given clk_hw pointer and a rate.
+
+Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com> # imx8mp
+Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> # exynos4210, meson g12b
+Signed-off-by: Maxime Ripard <maxime@cerno.tech>
+---
+ drivers/clk/clk.c            | 20 ++++++++++++++++++++
+ include/linux/clk-provider.h |  6 ++++++
+ 2 files changed, 26 insertions(+)
+
+--- a/drivers/clk/clk.c
++++ b/drivers/clk/clk.c
+@@ -1395,6 +1395,26 @@ static void clk_core_init_rate_req(struc
+ 	}
+ }
+ 
++/**
++ * clk_hw_init_rate_request - Initializes a clk_rate_request
++ * @hw: the clk for which we want to submit a rate request
++ * @req: the clk_rate_request structure we want to initialise
++ * @rate: the rate which is to be requested
++ *
++ * Initializes and fills a clk_rate_request structure to submit to
++ * __clk_determine_rate or similar functions.
++ */
++void clk_hw_init_rate_request(struct clk_hw * const hw,
++			      struct clk_rate_request *req,
++			      unsigned long rate)
++{
++	if (WARN_ON(!hw || !req))
++		return;
++
++	clk_core_init_rate_req(hw->core, req, rate);
++}
++EXPORT_SYMBOL_GPL(clk_hw_init_rate_request);
++
+ static bool clk_core_can_round(struct clk_core * const core)
+ {
+ 	return core->ops->determine_rate || core->ops->round_rate;
+--- a/include/linux/clk-provider.h
++++ b/include/linux/clk-provider.h
+@@ -42,6 +42,8 @@ struct dentry;
+  * struct clk_rate_request - Structure encoding the clk constraints that
+  * a clock user might require.
+  *
++ * Should be initialized by calling clk_hw_init_rate_request().
++ *
+  * @rate:		Requested clock rate. This field will be adjusted by
+  *			clock drivers according to hardware capabilities.
+  * @min_rate:		Minimum rate imposed by clk users.
+@@ -60,6 +62,10 @@ struct clk_rate_request {
+ 	struct clk_hw *best_parent_hw;
+ };
+ 
++void clk_hw_init_rate_request(struct clk_hw * const hw,
++			      struct clk_rate_request *req,
++			      unsigned long rate);
++
+ /**
+  * struct clk_duty - Struture encoding the duty cycle ratio of a clock
+  *