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-rw-r--r--target/linux/sunxi/patches-4.9/0003-clk-sunxi-ng-Remove-the-use-of-rational-computations.patch239
1 files changed, 239 insertions, 0 deletions
diff --git a/target/linux/sunxi/patches-4.9/0003-clk-sunxi-ng-Remove-the-use-of-rational-computations.patch b/target/linux/sunxi/patches-4.9/0003-clk-sunxi-ng-Remove-the-use-of-rational-computations.patch
new file mode 100644
index 0000000000..6b8f46eae0
--- /dev/null
+++ b/target/linux/sunxi/patches-4.9/0003-clk-sunxi-ng-Remove-the-use-of-rational-computations.patch
@@ -0,0 +1,239 @@
+From ee28648cb2b4d4ab5c2eb8199ea86675fe19016b Mon Sep 17 00:00:00 2001
+From: Maxime Ripard <maxime.ripard@free-electrons.com>
+Date: Thu, 29 Sep 2016 22:53:12 +0200
+Subject: clk: sunxi-ng: Remove the use of rational computations
+
+While the rational library works great, it doesn't really allow us to add
+more constraints, like the minimum.
+
+Remove that in order to be able to deal with the constraints we'll need.
+
+Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
+Acked-by: Chen-Yu Tsai <wens@csie.org>
+---
+ drivers/clk/sunxi-ng/Kconfig | 3 ---
+ drivers/clk/sunxi-ng/ccu_nkm.c | 31 ++++++++++++-----------
+ drivers/clk/sunxi-ng/ccu_nkmp.c | 37 ++++++++++++++--------------
+ drivers/clk/sunxi-ng/ccu_nm.c | 54 +++++++++++++++++++++++++++++++----------
+ 4 files changed, 74 insertions(+), 51 deletions(-)
+
+--- a/drivers/clk/sunxi-ng/Kconfig
++++ b/drivers/clk/sunxi-ng/Kconfig
+@@ -35,17 +35,14 @@ config SUNXI_CCU_NK
+
+ config SUNXI_CCU_NKM
+ bool
+- select RATIONAL
+ select SUNXI_CCU_GATE
+
+ config SUNXI_CCU_NKMP
+ bool
+- select RATIONAL
+ select SUNXI_CCU_GATE
+
+ config SUNXI_CCU_NM
+ bool
+- select RATIONAL
+ select SUNXI_CCU_FRAC
+ select SUNXI_CCU_GATE
+
+--- a/drivers/clk/sunxi-ng/ccu_nkm.c
++++ b/drivers/clk/sunxi-ng/ccu_nkm.c
+@@ -9,7 +9,6 @@
+ */
+
+ #include <linux/clk-provider.h>
+-#include <linux/rational.h>
+
+ #include "ccu_gate.h"
+ #include "ccu_nkm.h"
+@@ -28,21 +27,21 @@ static void ccu_nkm_find_best(unsigned l
+ unsigned long _n, _k, _m;
+
+ for (_k = 1; _k <= nkm->max_k; _k++) {
+- unsigned long tmp_rate;
+-
+- rational_best_approximation(rate / _k, parent,
+- nkm->max_n, nkm->max_m, &_n, &_m);
+-
+- tmp_rate = parent * _n * _k / _m;
+-
+- if (tmp_rate > rate)
+- continue;
+-
+- if ((rate - tmp_rate) < (rate - best_rate)) {
+- best_rate = tmp_rate;
+- best_n = _n;
+- best_k = _k;
+- best_m = _m;
++ for (_n = 1; _n <= nkm->max_n; _n++) {
++ for (_m = 1; _n <= nkm->max_m; _m++) {
++ unsigned long tmp_rate;
++
++ tmp_rate = parent * _n * _k / _m;
++
++ if (tmp_rate > rate)
++ continue;
++ if ((rate - tmp_rate) < (rate - best_rate)) {
++ best_rate = tmp_rate;
++ best_n = _n;
++ best_k = _k;
++ best_m = _m;
++ }
++ }
+ }
+ }
+
+--- a/drivers/clk/sunxi-ng/ccu_nkmp.c
++++ b/drivers/clk/sunxi-ng/ccu_nkmp.c
+@@ -9,7 +9,6 @@
+ */
+
+ #include <linux/clk-provider.h>
+-#include <linux/rational.h>
+
+ #include "ccu_gate.h"
+ #include "ccu_nkmp.h"
+@@ -29,24 +28,24 @@ static void ccu_nkmp_find_best(unsigned
+ unsigned long _n, _k, _m, _p;
+
+ for (_k = 1; _k <= nkmp->max_k; _k++) {
+- for (_p = 1; _p <= nkmp->max_p; _p <<= 1) {
+- unsigned long tmp_rate;
+-
+- rational_best_approximation(rate / _k, parent / _p,
+- nkmp->max_n, nkmp->max_m,
+- &_n, &_m);
+-
+- tmp_rate = parent * _n * _k / (_m * _p);
+-
+- if (tmp_rate > rate)
+- continue;
+-
+- if ((rate - tmp_rate) < (rate - best_rate)) {
+- best_rate = tmp_rate;
+- best_n = _n;
+- best_k = _k;
+- best_m = _m;
+- best_p = _p;
++ for (_n = 1; _n <= nkmp->max_n; _n++) {
++ for (_m = 1; _n <= nkmp->max_m; _m++) {
++ for (_p = 1; _p <= nkmp->max_p; _p <<= 1) {
++ unsigned long tmp_rate;
++
++ tmp_rate = parent * _n * _k / (_m * _p);
++
++ if (tmp_rate > rate)
++ continue;
++
++ if ((rate - tmp_rate) < (rate - best_rate)) {
++ best_rate = tmp_rate;
++ best_n = _n;
++ best_k = _k;
++ best_m = _m;
++ best_p = _p;
++ }
++ }
+ }
+ }
+ }
+--- a/drivers/clk/sunxi-ng/ccu_nm.c
++++ b/drivers/clk/sunxi-ng/ccu_nm.c
+@@ -9,12 +9,42 @@
+ */
+
+ #include <linux/clk-provider.h>
+-#include <linux/rational.h>
+
+ #include "ccu_frac.h"
+ #include "ccu_gate.h"
+ #include "ccu_nm.h"
+
++struct _ccu_nm {
++ unsigned long n, max_n;
++ unsigned long m, max_m;
++};
++
++static void ccu_nm_find_best(unsigned long parent, unsigned long rate,
++ struct _ccu_nm *nm)
++{
++ unsigned long best_rate = 0;
++ unsigned long best_n = 0, best_m = 0;
++ unsigned long _n, _m;
++
++ for (_n = 1; _n <= nm->max_n; _n++) {
++ for (_m = 1; _n <= nm->max_m; _m++) {
++ unsigned long tmp_rate = parent * _n / _m;
++
++ if (tmp_rate > rate)
++ continue;
++
++ if ((rate - tmp_rate) < (rate - best_rate)) {
++ best_rate = tmp_rate;
++ best_n = _n;
++ best_m = _m;
++ }
++ }
++ }
++
++ nm->n = best_n;
++ nm->m = best_m;
++}
++
+ static void ccu_nm_disable(struct clk_hw *hw)
+ {
+ struct ccu_nm *nm = hw_to_ccu_nm(hw);
+@@ -61,24 +91,22 @@ static long ccu_nm_round_rate(struct clk
+ unsigned long *parent_rate)
+ {
+ struct ccu_nm *nm = hw_to_ccu_nm(hw);
+- unsigned long max_n, max_m;
+- unsigned long n, m;
++ struct _ccu_nm _nm;
+
+- max_n = 1 << nm->n.width;
+- max_m = nm->m.max ?: 1 << nm->m.width;
++ _nm.max_n = 1 << nm->n.width;
++ _nm.max_m = nm->m.max ?: 1 << nm->m.width;
+
+- rational_best_approximation(rate, *parent_rate, max_n, max_m, &n, &m);
++ ccu_nm_find_best(*parent_rate, rate, &_nm);
+
+- return *parent_rate * n / m;
++ return *parent_rate * _nm.n / _nm.m;
+ }
+
+ static int ccu_nm_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+ {
+ struct ccu_nm *nm = hw_to_ccu_nm(hw);
++ struct _ccu_nm _nm;
+ unsigned long flags;
+- unsigned long max_n, max_m;
+- unsigned long n, m;
+ u32 reg;
+
+ if (ccu_frac_helper_has_rate(&nm->common, &nm->frac, rate))
+@@ -86,10 +114,10 @@ static int ccu_nm_set_rate(struct clk_hw
+ else
+ ccu_frac_helper_disable(&nm->common, &nm->frac);
+
+- max_n = 1 << nm->n.width;
+- max_m = nm->m.max ?: 1 << nm->m.width;
++ _nm.max_n = 1 << nm->n.width;
++ _nm.max_m = nm->m.max ?: 1 << nm->m.width;
+
+- rational_best_approximation(rate, parent_rate, max_n, max_m, &n, &m);
++ ccu_nm_find_best(parent_rate, rate, &_nm);
+
+ spin_lock_irqsave(nm->common.lock, flags);
+
+@@ -97,7 +125,7 @@ static int ccu_nm_set_rate(struct clk_hw
+ reg &= ~GENMASK(nm->n.width + nm->n.shift - 1, nm->n.shift);
+ reg &= ~GENMASK(nm->m.width + nm->m.shift - 1, nm->m.shift);
+
+- writel(reg | ((m - 1) << nm->m.shift) | ((n - 1) << nm->n.shift),
++ writel(reg | ((_nm.m - 1) << nm->m.shift) | ((_nm.n - 1) << nm->n.shift),
+ nm->common.base + nm->common.reg);
+
+ spin_unlock_irqrestore(nm->common.lock, flags);