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authorMaxime Ripard <maxime.ripard@free-electrons.com>2016-09-29 22:53:12 +0200
committerMaxime Ripard <maxime.ripard@free-electrons.com>2016-10-25 12:39:25 +0200
commitee28648cb2b4d4ab5c2eb8199ea86675fe19016b (patch)
tree12dc3739b8f2268d87d3fcc909663c61932a5447
parenta501a14e38cc4d8e9c91bb508cdca7032d53f717 (diff)
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>
-rw-r--r--drivers/clk/sunxi-ng/Kconfig3
-rw-r--r--drivers/clk/sunxi-ng/ccu_nkm.c31
-rw-r--r--drivers/clk/sunxi-ng/ccu_nkmp.c37
-rw-r--r--drivers/clk/sunxi-ng/ccu_nm.c54
4 files changed, 74 insertions, 51 deletions
diff --git a/drivers/clk/sunxi-ng/Kconfig b/drivers/clk/sunxi-ng/Kconfig
index 254d952..1b4c55a 100644
--- 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
diff --git a/drivers/clk/sunxi-ng/ccu_nkm.c b/drivers/clk/sunxi-ng/ccu_nkm.c
index 059fdc3..0b08d00 100644
--- 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 long parent, unsigned long rate,
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;
+ }
+ }
}
}
diff --git a/drivers/clk/sunxi-ng/ccu_nkmp.c b/drivers/clk/sunxi-ng/ccu_nkmp.c
index 9769dee..fcf6757 100644
--- 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 long parent, unsigned long rate,
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;
+ }
+ }
}
}
}
diff --git a/drivers/clk/sunxi-ng/ccu_nm.c b/drivers/clk/sunxi-ng/ccu_nm.c
index b61bdd8..c6d6522 100644
--- 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_hw *hw, unsigned long rate,
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 *hw, unsigned long rate,
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 *hw, unsigned long rate,
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);