diff mbox series

[3/3] ram: rk3399: Conduct memory training at 400MHz

Message ID 20220621100729.979275-3-lee.jones@linaro.org
State New
Headers show
Series [1/3] ram: rk3399: Fix .set_rate_index() error handling | expand

Commit Message

Lee Jones June 21, 2022, 10:07 a.m. UTC
Currently the default initialisation frequency is 50MHz.  Although
this does appear to be suitable for some LPDDR4 RAM chips, training at
this low frequency has been seen to cause Column errors, leading to
Capacity check errors on others.

Here we force RAM initialisation to happen at 400MHz before ramping up
to the final value running value of 800MHz after everything has been
successfully configured.

Link: https://lore.kernel.org/u-boot/Yo4v3jUeHXTovjOH@google.com/
Suggested-by: YouMin Chen <cym@rock-chips.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
---
 drivers/ram/rockchip/sdram_rk3399.c | 36 +++++++++++++++++------------
 1 file changed, 21 insertions(+), 15 deletions(-)

Comments

Kever Yang July 1, 2022, 12:05 p.m. UTC | #1
On 2022/6/21 18:07, Lee Jones wrote:
> Currently the default initialisation frequency is 50MHz.  Although
> this does appear to be suitable for some LPDDR4 RAM chips, training at
> this low frequency has been seen to cause Column errors, leading to
> Capacity check errors on others.
>
> Here we force RAM initialisation to happen at 400MHz before ramping up
> to the final value running value of 800MHz after everything has been
> successfully configured.
>
> Link: https://lore.kernel.org/u-boot/Yo4v3jUeHXTovjOH@google.com/
> Suggested-by: YouMin Chen <cym@rock-chips.com>
> Signed-off-by: Lee Jones <lee.jones@linaro.org>

Reviewed-by: Kever Yang <kever.yang@rock-chips.com>

Thanks,
- Kever
> ---
>   drivers/ram/rockchip/sdram_rk3399.c | 36 +++++++++++++++++------------
>   1 file changed, 21 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/ram/rockchip/sdram_rk3399.c b/drivers/ram/rockchip/sdram_rk3399.c
> index 34d6c93f95..b05c5925d5 100644
> --- a/drivers/ram/rockchip/sdram_rk3399.c
> +++ b/drivers/ram/rockchip/sdram_rk3399.c
> @@ -85,7 +85,7 @@ struct sdram_rk3399_ops {
>   	int (*data_training_first)(struct dram_info *dram, u32 channel, u8 rank,
>   				   struct rk3399_sdram_params *sdram);
>   	int (*set_rate_index)(struct dram_info *dram,
> -			      struct rk3399_sdram_params *params);
> +			      struct rk3399_sdram_params *params, u32 ctl_fn);
>   	void (*modify_param)(const struct chan_info *chan,
>   			     struct rk3399_sdram_params *params);
>   	struct rk3399_sdram_params *
> @@ -1644,7 +1644,8 @@ static int data_training_first(struct dram_info *dram, u32 channel, u8 rank,
>   }
>   
>   static int switch_to_phy_index1(struct dram_info *dram,
> -				struct rk3399_sdram_params *params)
> +				struct rk3399_sdram_params *params,
> +				u32 unused)
>   {
>   	u32 channel;
>   	u32 *denali_phy;
> @@ -2539,26 +2540,25 @@ static int lpddr4_set_ctl(struct dram_info *dram,
>   }
>   
>   static int lpddr4_set_rate(struct dram_info *dram,
> -			   struct rk3399_sdram_params *params)
> +			    struct rk3399_sdram_params *params,
> +			    u32 ctl_fn)
>   {
> -	u32 ctl_fn;
>   	u32 phy_fn;
>   
> -	for (ctl_fn = 0; ctl_fn < 2; ctl_fn++) {
> -		phy_fn = lpddr4_get_phy_fn(params, ctl_fn);
> +	phy_fn = lpddr4_get_phy_fn(params, ctl_fn);
>   
> -		lpddr4_set_phy(dram, params, phy_fn, &dfs_cfgs_lpddr4[ctl_fn]);
> -		lpddr4_set_ctl(dram, params, ctl_fn,
> -			       dfs_cfgs_lpddr4[ctl_fn].base.ddr_freq);
> +	lpddr4_set_phy(dram, params, phy_fn, &dfs_cfgs_lpddr4[ctl_fn]);
> +	lpddr4_set_ctl(dram, params, ctl_fn,
> +		       dfs_cfgs_lpddr4[ctl_fn].base.ddr_freq);
>   
> -		if (IS_ENABLED(CONFIG_RAM_ROCKCHIP_DEBUG))
> -			printf("%s: change freq to %dMHz %d, %d\n", __func__,
> -			       dfs_cfgs_lpddr4[ctl_fn].base.ddr_freq / MHz,
> -			       ctl_fn, phy_fn);
> -	}
> +	if (IS_ENABLED(CONFIG_RAM_ROCKCHIP_DEBUG))
> +		printf("%s: change freq to %dMHz %d, %d\n", __func__,
> +		       dfs_cfgs_lpddr4[ctl_fn].base.ddr_freq / MHz,
> +		       ctl_fn, phy_fn);
>   
>   	return 0;
>   }
> +
>   #endif /* CONFIG_RAM_RK3399_LPDDR4 */
>   
>   /* CS0,n=1
> @@ -2955,6 +2955,12 @@ static int sdram_init(struct dram_info *dram,
>   		params->ch[ch].cap_info.rank = rank;
>   	}
>   
> +#if defined(CONFIG_RAM_RK3399_LPDDR4)
> +	/* LPDDR4 needs to be trained at 400MHz */
> +	lpddr4_set_rate(dram, params, 0);
> +	params->base.ddr_freq = dfs_cfgs_lpddr4[0].base.ddr_freq / MHz;
> +#endif
> +
>   	params->base.num_channels = 0;
>   	for (channel = 0; channel < 2; channel++) {
>   		const struct chan_info *chan = &dram->chan[channel];
> @@ -3005,7 +3011,7 @@ static int sdram_init(struct dram_info *dram,
>   	params->base.stride = calculate_stride(params);
>   	dram_all_config(dram, params);
>   
> -	ret = dram->ops->set_rate_index(dram, params);
> +	ret = dram->ops->set_rate_index(dram, params, 1);
>   	if (ret)
>   		return ret;
>
Xavier Drudis Ferran July 4, 2022, 10:01 a.m. UTC | #2
El Tue, Jun 21, 2022 at 10:07:29AM +0000, Lee Jones deia:
> Currently the default initialisation frequency is 50MHz.  Although
> this does appear to be suitable for some LPDDR4 RAM chips, training at
> this low frequency has been seen to cause Column errors, leading to
> Capacity check errors on others.
> 
> Here we force RAM initialisation to happen at 400MHz before ramping up
> to the final value running value of 800MHz after everything has been
> successfully configured.
> 
> Link: https://lore.kernel.org/u-boot/Yo4v3jUeHXTovjOH@google.com/
> Suggested-by: YouMin Chen <cym@rock-chips.com>
> Signed-off-by: Lee Jones <lee.jones@linaro.org>

My board doesn't suffer with the issue resolved by this series,
however I did apply it and nothing regressed.

Tested-by: Xavier Drudis Ferran <xdrudis@tinet.cat>

> ---
>  drivers/ram/rockchip/sdram_rk3399.c | 36 +++++++++++++++++------------
>  1 file changed, 21 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/ram/rockchip/sdram_rk3399.c b/drivers/ram/rockchip/sdram_rk3399.c
> index 34d6c93f95..b05c5925d5 100644
> --- a/drivers/ram/rockchip/sdram_rk3399.c
> +++ b/drivers/ram/rockchip/sdram_rk3399.c
> @@ -85,7 +85,7 @@ struct sdram_rk3399_ops {
>  	int (*data_training_first)(struct dram_info *dram, u32 channel, u8 rank,
>  				   struct rk3399_sdram_params *sdram);
>  	int (*set_rate_index)(struct dram_info *dram,
> -			      struct rk3399_sdram_params *params);
> +			      struct rk3399_sdram_params *params, u32 ctl_fn);
>  	void (*modify_param)(const struct chan_info *chan,
>  			     struct rk3399_sdram_params *params);
>  	struct rk3399_sdram_params *
> @@ -1644,7 +1644,8 @@ static int data_training_first(struct dram_info *dram, u32 channel, u8 rank,
>  }
>  
>  static int switch_to_phy_index1(struct dram_info *dram,
> -				struct rk3399_sdram_params *params)
> +				struct rk3399_sdram_params *params,
> +				u32 unused)
>  {
>  	u32 channel;
>  	u32 *denali_phy;
> @@ -2539,26 +2540,25 @@ static int lpddr4_set_ctl(struct dram_info *dram,
>  }
>  
>  static int lpddr4_set_rate(struct dram_info *dram,
> -			   struct rk3399_sdram_params *params)
> +			    struct rk3399_sdram_params *params,
> +			    u32 ctl_fn)
>  {
> -	u32 ctl_fn;
>  	u32 phy_fn;
>  
> -	for (ctl_fn = 0; ctl_fn < 2; ctl_fn++) {
> -		phy_fn = lpddr4_get_phy_fn(params, ctl_fn);
> +	phy_fn = lpddr4_get_phy_fn(params, ctl_fn);
>  
> -		lpddr4_set_phy(dram, params, phy_fn, &dfs_cfgs_lpddr4[ctl_fn]);
> -		lpddr4_set_ctl(dram, params, ctl_fn,
> -			       dfs_cfgs_lpddr4[ctl_fn].base.ddr_freq);
> +	lpddr4_set_phy(dram, params, phy_fn, &dfs_cfgs_lpddr4[ctl_fn]);
> +	lpddr4_set_ctl(dram, params, ctl_fn,
> +		       dfs_cfgs_lpddr4[ctl_fn].base.ddr_freq);
>  
> -		if (IS_ENABLED(CONFIG_RAM_ROCKCHIP_DEBUG))
> -			printf("%s: change freq to %dMHz %d, %d\n", __func__,
> -			       dfs_cfgs_lpddr4[ctl_fn].base.ddr_freq / MHz,
> -			       ctl_fn, phy_fn);
> -	}
> +	if (IS_ENABLED(CONFIG_RAM_ROCKCHIP_DEBUG))
> +		printf("%s: change freq to %dMHz %d, %d\n", __func__,
> +		       dfs_cfgs_lpddr4[ctl_fn].base.ddr_freq / MHz,
> +		       ctl_fn, phy_fn);
>  
>  	return 0;
>  }
> +
>  #endif /* CONFIG_RAM_RK3399_LPDDR4 */
>  
>  /* CS0,n=1
> @@ -2955,6 +2955,12 @@ static int sdram_init(struct dram_info *dram,
>  		params->ch[ch].cap_info.rank = rank;
>  	}
>  
> +#if defined(CONFIG_RAM_RK3399_LPDDR4)
> +	/* LPDDR4 needs to be trained at 400MHz */
> +	lpddr4_set_rate(dram, params, 0);
> +	params->base.ddr_freq = dfs_cfgs_lpddr4[0].base.ddr_freq / MHz;
> +#endif
> +
>  	params->base.num_channels = 0;
>  	for (channel = 0; channel < 2; channel++) {
>  		const struct chan_info *chan = &dram->chan[channel];
> @@ -3005,7 +3011,7 @@ static int sdram_init(struct dram_info *dram,
>  	params->base.stride = calculate_stride(params);
>  	dram_all_config(dram, params);
>  
> -	ret = dram->ops->set_rate_index(dram, params);
> +	ret = dram->ops->set_rate_index(dram, params, 1);
>  	if (ret)
>  		return ret;
>  
> -- 
> 2.37.0.rc0.104.g0611611a94-goog
>
diff mbox series

Patch

diff --git a/drivers/ram/rockchip/sdram_rk3399.c b/drivers/ram/rockchip/sdram_rk3399.c
index 34d6c93f95..b05c5925d5 100644
--- a/drivers/ram/rockchip/sdram_rk3399.c
+++ b/drivers/ram/rockchip/sdram_rk3399.c
@@ -85,7 +85,7 @@  struct sdram_rk3399_ops {
 	int (*data_training_first)(struct dram_info *dram, u32 channel, u8 rank,
 				   struct rk3399_sdram_params *sdram);
 	int (*set_rate_index)(struct dram_info *dram,
-			      struct rk3399_sdram_params *params);
+			      struct rk3399_sdram_params *params, u32 ctl_fn);
 	void (*modify_param)(const struct chan_info *chan,
 			     struct rk3399_sdram_params *params);
 	struct rk3399_sdram_params *
@@ -1644,7 +1644,8 @@  static int data_training_first(struct dram_info *dram, u32 channel, u8 rank,
 }
 
 static int switch_to_phy_index1(struct dram_info *dram,
-				struct rk3399_sdram_params *params)
+				struct rk3399_sdram_params *params,
+				u32 unused)
 {
 	u32 channel;
 	u32 *denali_phy;
@@ -2539,26 +2540,25 @@  static int lpddr4_set_ctl(struct dram_info *dram,
 }
 
 static int lpddr4_set_rate(struct dram_info *dram,
-			   struct rk3399_sdram_params *params)
+			    struct rk3399_sdram_params *params,
+			    u32 ctl_fn)
 {
-	u32 ctl_fn;
 	u32 phy_fn;
 
-	for (ctl_fn = 0; ctl_fn < 2; ctl_fn++) {
-		phy_fn = lpddr4_get_phy_fn(params, ctl_fn);
+	phy_fn = lpddr4_get_phy_fn(params, ctl_fn);
 
-		lpddr4_set_phy(dram, params, phy_fn, &dfs_cfgs_lpddr4[ctl_fn]);
-		lpddr4_set_ctl(dram, params, ctl_fn,
-			       dfs_cfgs_lpddr4[ctl_fn].base.ddr_freq);
+	lpddr4_set_phy(dram, params, phy_fn, &dfs_cfgs_lpddr4[ctl_fn]);
+	lpddr4_set_ctl(dram, params, ctl_fn,
+		       dfs_cfgs_lpddr4[ctl_fn].base.ddr_freq);
 
-		if (IS_ENABLED(CONFIG_RAM_ROCKCHIP_DEBUG))
-			printf("%s: change freq to %dMHz %d, %d\n", __func__,
-			       dfs_cfgs_lpddr4[ctl_fn].base.ddr_freq / MHz,
-			       ctl_fn, phy_fn);
-	}
+	if (IS_ENABLED(CONFIG_RAM_ROCKCHIP_DEBUG))
+		printf("%s: change freq to %dMHz %d, %d\n", __func__,
+		       dfs_cfgs_lpddr4[ctl_fn].base.ddr_freq / MHz,
+		       ctl_fn, phy_fn);
 
 	return 0;
 }
+
 #endif /* CONFIG_RAM_RK3399_LPDDR4 */
 
 /* CS0,n=1
@@ -2955,6 +2955,12 @@  static int sdram_init(struct dram_info *dram,
 		params->ch[ch].cap_info.rank = rank;
 	}
 
+#if defined(CONFIG_RAM_RK3399_LPDDR4)
+	/* LPDDR4 needs to be trained at 400MHz */
+	lpddr4_set_rate(dram, params, 0);
+	params->base.ddr_freq = dfs_cfgs_lpddr4[0].base.ddr_freq / MHz;
+#endif
+
 	params->base.num_channels = 0;
 	for (channel = 0; channel < 2; channel++) {
 		const struct chan_info *chan = &dram->chan[channel];
@@ -3005,7 +3011,7 @@  static int sdram_init(struct dram_info *dram,
 	params->base.stride = calculate_stride(params);
 	dram_all_config(dram, params);
 
-	ret = dram->ops->set_rate_index(dram, params);
+	ret = dram->ops->set_rate_index(dram, params, 1);
 	if (ret)
 		return ret;