github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-07-31 19:47:08 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

clk: qcom: clk-rcg2: Add support to force enable an RCG

Browse Source 
In certain cases, it is desirable for an RCG to be turned on
explicitly instead of just relying on the enable signal from
its branch clock(s). Add support for this.

Change-Id: I2b0b81bddfe7cc7543c313e4ed13a332fb1a0fcb
Signed-off-by: Deepak Katragadda <dkatraga@codeaurora.org>
Signed-off-by: David Dai <daidavid1@codeaurora.org>
This commit is contained in:
Deepak Katragadda 2018-09-11 15:09:03 -07:00 committed by Mike Tipton
parent 76ec230456
commit 356aa27ef3
2 changed files with 91 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
drivers/clk/qcom/clk-rcg.h
View File

@ -141,6 +141,7 @@ extern const struct clk_ops clk_dyn_rcg_ops;
* @enable_safe_config: When set, the RCG is parked at CXO when it's disabled
* @clkr: regmap clock handle
* @cfg_off: defines the cfg register offset from the CMD_RCGR + CFG_REG
* @flags: additional flag parameters for the RCG
*/
struct clk_rcg2 {
u32 cmd_rcgr;
@ -153,6 +154,8 @@ struct clk_rcg2 {
bool enable_safe_config;
struct clk_regmap clkr;
u8 cfg_off;
u8 flags;
#define FORCE_ENABLE_RCG BIT(0)
};
#define to_clk_rcg2(_hw) container_of(to_clk_regmap(_hw), struct clk_rcg2, clkr)

90
drivers/clk/qcom/clk-rcg2.c
View File

@ -175,6 +175,47 @@ static int clk_rcg2_clear_force_enable(struct clk_hw *hw)
CMD_ROOT_EN, 0);
}
static int prepare_enable_rcg_srcs(struct clk *curr, struct clk *new)
{
int rc = 0;
rc = clk_prepare(curr);
if (rc)
return rc;
rc = clk_prepare(new);
if (rc)
goto err_new_src_prepare;
rc = clk_enable(curr);
if (rc)
goto err_curr_src_enable;
rc = clk_enable(new);
if (rc)
goto err_new_src_enable;
return rc;
err_new_src_enable:
clk_disable(curr);
err_curr_src_enable:
clk_unprepare(new);
err_new_src_prepare:
clk_unprepare(curr);
return rc;
}
static void disable_unprepare_rcg_srcs(struct clk *curr, struct clk *new)
{
clk_disable(new);
clk_disable(curr);
clk_unprepare(new);
clk_unprepare(curr);
}
/*
* Calculate m/n:d rate
*
@ -358,8 +399,9 @@ static int __clk_rcg2_set_rate(struct clk_hw *hw, unsigned long rate,
enum freq_policy policy)
{
struct clk_rcg2 *rcg = to_clk_rcg2(hw);
const struct freq_tbl *f;
int ret;
const struct freq_tbl *f, *f_curr;
int ret, curr_src_index, new_src_index;
struct clk_hw *curr_src = NULL, *new_src = NULL;
switch (policy) {
case FLOOR:
@ -384,10 +426,44 @@ static int __clk_rcg2_set_rate(struct clk_hw *hw, unsigned long rate,
return 0;
}
if (rcg->flags & FORCE_ENABLE_RCG) {
rcg->current_freq = clk_get_rate(hw->clk);
if (rcg->current_freq == cxo_f.freq)
curr_src_index = 0;
else {
f_curr = qcom_find_freq(rcg->freq_tbl,
rcg->current_freq);
if (!f_curr)
return -EINVAL;
curr_src_index = qcom_find_src_index(hw,
rcg->parent_map, f_curr->src);
}
new_src_index = qcom_find_src_index(hw, rcg->parent_map,
f->src);
curr_src = clk_hw_get_parent_by_index(hw, curr_src_index);
if (!curr_src)
return -EINVAL;
new_src = clk_hw_get_parent_by_index(hw, new_src_index);
if (!new_src)
return -EINVAL;
/* The RCG could currently be disabled. Enable its parents. */
ret = prepare_enable_rcg_srcs(curr_src->clk, new_src->clk);
clk_rcg2_set_force_enable(hw);
}
ret = clk_rcg2_configure(rcg, f);
if (ret)
return ret;
if (rcg->flags & FORCE_ENABLE_RCG) {
clk_rcg2_clear_force_enable(hw);
disable_unprepare_rcg_srcs(curr_src->clk, new_src->clk);
}
/* Update current frequency with the requested frequency. */
rcg->current_freq = rate;
return ret;
@ -500,6 +576,11 @@ static int clk_rcg2_enable(struct clk_hw *hw)
unsigned long rate;
const struct freq_tbl *f;
if (rcg->flags & FORCE_ENABLE_RCG) {
clk_rcg2_set_force_enable(hw);
return 0;
}
if (!rcg->enable_safe_config)
return 0;
@ -536,6 +617,11 @@ static void clk_rcg2_disable(struct clk_hw *hw)
{
struct clk_rcg2 *rcg = to_clk_rcg2(hw);
if (rcg->flags & FORCE_ENABLE_RCG) {
clk_rcg2_clear_force_enable(hw);
return;
}
if (!rcg->enable_safe_config)
return;
/*