When enabling/disabling a clock or reset signal, confirm that the change has completed before returning from the function. A somewhat arbitrary 100ms timeout is defined to ensure that the system doesn't lock up in the case of an error.
Since we need to dynamically determine if we're waiting for a 0 bit or a 1 bit, it's easier to use wait_for_bit_32() than readl_poll_timeout().
This change is needed for reliable initialization of the I2C driver which is added in a following patch.
Fixes: 1918ff5c95be ("clk: renesas: Add RZ/G2L & RZ/G2LC CPG driver") Signed-off-by: Paul Barker paul.barker.ct@bp.renesas.com --- drivers/clk/renesas/rzg2l-cpg.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-)
diff --git a/drivers/clk/renesas/rzg2l-cpg.c b/drivers/clk/renesas/rzg2l-cpg.c index e54508c35ce2..dba009997a81 100644 --- a/drivers/clk/renesas/rzg2l-cpg.c +++ b/drivers/clk/renesas/rzg2l-cpg.c @@ -23,10 +23,18 @@ #include <linux/iopoll.h> #include <reset-uclass.h> #include <reset.h> +#include <wait_bit.h>
#include "rzg2l-cpg.h"
+/* + * Monitor registers for both clock and reset signals are offset by 0x180 from + * the corresponding control registers. + */ #define CLK_MON_R(reg) (0x180 + (reg)) +#define RST_MON_R(reg) (0x180 + (reg)) + +#define CPG_TIMEOUT_MSEC 100
static ulong rzg2l_cpg_clk_get_rate_by_id(struct udevice *dev, unsigned int id); static ulong rzg2l_cpg_clk_get_rate_by_name(struct udevice *dev, const char *name); @@ -83,9 +91,9 @@ static int rzg2l_cpg_clk_set(struct clk *clk, bool enable) value |= BIT(mod_clk->bit); writel(value, data->base + mod_clk->off);
- if (enable && readl_poll_timeout(data->base + CLK_MON_R(mod_clk->off), - value, (value & BIT(mod_clk->bit)), - 10)) { + if (enable && wait_for_bit_32(data->base + CLK_MON_R(mod_clk->off), + BIT(mod_clk->bit), enable, + CPG_TIMEOUT_MSEC, false)) { dev_err(clk->dev, "Timeout\n"); return -ETIMEDOUT; } @@ -420,7 +428,8 @@ static int rzg2l_cpg_rst_set(struct reset_ctl *reset_ctl, bool asserted) value |= BIT(rst->bit); writel(value, data->base + rst->off);
- return 0; + return wait_for_bit_32(data->base + RST_MON_R(rst->off), BIT(rst->bit), + asserted, CPG_TIMEOUT_MSEC, false); }
static int rzg2l_cpg_rst_assert(struct reset_ctl *reset_ctl)