[PATCH] ddr: marvell: a38x: Fix unsigned issues

[Stefan Roese]

On 28.07.25 16:26, Andrew Goodbody wrote:
> Cannot test an unsigned variable to be less than 0, it will always fail.
> 
> Signed-off-by: Andrew Goodbody <andrew.goodbody at linaro.org>

Reviewed-by: Stefan Roese <stefan.roese at mailbox.org>

Thanks,
Stefan

> ---
>   drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c | 13 +++++++------
>   1 file changed, 7 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c b/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c
> index 31b6209416b..84156a1e8ad 100644
> --- a/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c
> +++ b/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c
> @@ -64,7 +64,7 @@ static u8 center_high_element_get(u8 dir, u8 pbs_element, u16 lambda, u8 pbs_max
>   static int mv_ddr4_centralization(u8 dev_num, u16 (*lambda)[MAX_BUS_NUM][BUS_WIDTH_IN_BITS], u8 (*copt)[MAX_BUS_NUM],
>   				  u8 (*pbs_result)[MAX_BUS_NUM][BUS_WIDTH_IN_BITS], u8 (*vw_size)[MAX_BUS_NUM],
>   				  u8 mode, u16 param0, u8 param1);
> -static int mv_ddr4_dqs_reposition(u8 dir, u16 *lambda, u8 *pbs_result, char delta, u8 *copt, u8 *dqs_pbs);
> +static int mv_ddr4_dqs_reposition(u8 dir, u16 *lambda, u8 *pbs_result, s8 delta, u8 *copt, u8 *dqs_pbs);
>   static int mv_ddr4_copt_get(u8 dir, u16 *lambda, u8 *vw_l, u8 *vw_h, u8 *pbs_result, u8 *copt);
>   static int mv_ddr4_center_of_mass_calc(u8 dev_num, u8 if_id, u8 subphy_num, u8 mode, u8 *vw_l, u8 *vw_h, u8 *vw_v,
>   				       u8 vw_num, u8 *v_opt, u8 *t_opt);
> @@ -659,7 +659,7 @@ static int mv_ddr4_centralization(u8 dev_num, u16 (*lambda)[MAX_BUS_NUM][BUS_WID
>   	} /* if_id */
>   
>   	/* restore cs enable value*/
> -	for (if_id = 0; if_id < MAX_INTERFACE_NUM - 1; if_id++) {
> +	for (if_id = 0; if_id < MAX_INTERFACE_NUM; if_id++) {
>   		VALIDATE_IF_ACTIVE(tm->if_act_mask, if_id);
>   		status = ddr3_tip_if_write(dev_num, ACCESS_TYPE_UNICAST, if_id, DUAL_DUNIT_CFG_REG,
>   					   cs_ena_reg_val[if_id], MASK_ALL_BITS);
> @@ -895,7 +895,7 @@ static int mv_ddr4_copt_get(u8 dir, u16 *lambda, u8 *vw_l, u8 *vw_h, u8 *pbs_res
>    * It provides with a solution for a single subphy (8 bits).
>    * The calling function is responsible for any additional pbs taps for dqs
>    */
> -static int mv_ddr4_dqs_reposition(u8 dir, u16 *lambda, u8 *pbs_result, char delta, u8 *copt, u8 *dqs_pbs)
> +static int mv_ddr4_dqs_reposition(u8 dir, u16 *lambda, u8 *pbs_result, s8 delta, u8 *copt, u8 *dqs_pbs)
>   {
>   	u8 dq_idx;
>   	u32 pbs_max_val = 0;
> @@ -952,7 +952,8 @@ static int mv_ddr4_center_of_mass_calc(u8 dev_num, u8 if_id, u8 subphy_num, u8 m
>   	int t_opt_temp = 0, v_opt_temp = 0;
>   	int vw_avg = 0, v_avg = 0;
>   	int s0 = 0, s1 = 0, s2 = 0, slope = 1, r_sq = 0;
> -	u32 d_min = 10000, reg_val = 0;
> +	u32 reg_val = 0;
> +	int d_min = 10000;
>   	int status;
>   
>   	/*
> @@ -2189,7 +2190,7 @@ int mv_ddr4_dm_tuning(u32 cs, u16 (*pbs_tap_factor)[MAX_BUS_NUM][BUS_WIDTH_IN_BI
>   				for (dq = 0; dq < BUS_WIDTH_IN_BITS; dq++) {
>   					idx = dq + subphy * BUS_WIDTH_IN_BITS;
>   					reg_val = new_dq_pbs[dq] - dq_pbs_diff;
> -					if (reg_val < 0) {
> +					if (new_dq_pbs[dq] < dq_pbs_diff) {
>   						DEBUG_DM_TUNING(DEBUG_LEVEL_ERROR,
>   								("unexpected negative value found\n"));
>   						return MV_FAIL;
> @@ -2267,7 +2268,7 @@ int mv_ddr4_dm_tuning(u32 cs, u16 (*pbs_tap_factor)[MAX_BUS_NUM][BUS_WIDTH_IN_BI
>   						idx = dq + subphy * BUS_WIDTH_IN_BITS;
>   						pad = dq_map_table[idx];
>   						reg_val = new_dq_pbs[dq] - dq_pbs_diff;
> -						if (reg_val < 0) {
> +						if (new_dq_pbs[dq] < dq_pbs_diff) {
>   							DEBUG_DM_TUNING(DEBUG_LEVEL_ERROR,
>   									("unexpected negative value found\n"));
>   							return MV_FAIL;
> 
> ---
> base-commit: 4c3b5fcd810081bd7f3c51859fe1b5f0c159803c
> change-id: 20250728-a38x_ddr-64c67d8a63a2
> 
> Best regards,