RE: [PATCH v2 21/21] ipmi: kcs_bmc_aspeed: Optionally apply status address

[ChiaWei Wang <chiawei_wang@xxxxxxxxxxxxxx>]

Reviewed-by: Chia-Wei Wang <chiawei_wang@xxxxxxxxxxxxxx>

> -----Original Message-----
> From: Andrew Jeffery <andrew@xxxxxxxx>
> Sent: Friday, March 19, 2021 2:28 PM
> To: openipmi-developer@xxxxxxxxxxxxxxxxxxxxx; openbmc@xxxxxxxxxxxxxxxx;
> minyard@xxxxxxx
> Subject: [PATCH v2 21/21] ipmi: kcs_bmc_aspeed: Optionally apply status
> address
> 
> Some Aspeed KCS devices can derive the status register address from the
> address of the data register. As such, the address of the status register can be
> implicit in the configuration if desired. On the other hand, sometimes address
> schemes might be requested that are incompatible with the default addressing
> scheme. Allow these requests where possible if the devicetree specifies the
> status register address.
> 
> Signed-off-by: Andrew Jeffery <andrew@xxxxxxxx>
> ---
>  drivers/char/ipmi/kcs_bmc_aspeed.c | 113 +++++++++++++++++++++--------
>  1 file changed, 81 insertions(+), 32 deletions(-)
> 
> diff --git a/drivers/char/ipmi/kcs_bmc_aspeed.c
> b/drivers/char/ipmi/kcs_bmc_aspeed.c
> index 7334b1f51dcc..98789b837690 100644
> --- a/drivers/char/ipmi/kcs_bmc_aspeed.c
> +++ b/drivers/char/ipmi/kcs_bmc_aspeed.c
> @@ -83,6 +83,8 @@
>  #define LPC_STR2             0x040
>  #define LPC_STR3             0x044
>  #define LPC_HICRB            0x100
> +#define     LPC_HICRB_EN16LADR2      BIT(5)
> +#define     LPC_HICRB_EN16LADR1      BIT(4)
>  #define     LPC_HICRB_IBFIE4         BIT(1)
>  #define     LPC_HICRB_LPC4E          BIT(0)
>  #define LPC_HICRC            0x104
> @@ -96,6 +98,11 @@
>  #define LPC_IDR4             0x114
>  #define LPC_ODR4             0x118
>  #define LPC_STR4             0x11C
> +#define LPC_LSADR12	     0x120
> +#define     LPC_LSADR12_LSADR2_MASK  GENMASK(31, 16)
> +#define     LPC_LSADR12_LSADR2_SHIFT 16
> +#define     LPC_LSADR12_LSADR1_MASK  GENMASK(15, 0)
> +#define     LPC_LSADR12_LSADR1_SHIFT 0
> 
>  #define OBE_POLL_PERIOD	     (HZ / 2)
> 
> @@ -123,7 +130,7 @@ struct aspeed_kcs_bmc {
> 
>  struct aspeed_kcs_of_ops {
>  	int (*get_channel)(struct platform_device *pdev);
> -	int (*get_io_address)(struct platform_device *pdev);
> +	int (*get_io_address)(struct platform_device *pdev, u32 addrs[2]);
>  };
> 
>  static inline struct aspeed_kcs_bmc *to_aspeed_kcs_bmc(struct
> kcs_bmc_device *kcs_bmc) @@ -217,38 +224,64 @@ static void
> aspeed_kcs_updateb(struct kcs_bmc_device *kcs_bmc, u32 reg, u8 mask,
>   *     C. KCS4
>   *        D / C : CA4h / CA5h
>   */
> -static void aspeed_kcs_set_address(struct kcs_bmc_device *kcs_bmc, u16
> addr)
> +static int aspeed_kcs_set_address(struct kcs_bmc_device *kcs_bmc, u32
> +addrs[2], int nr_addrs)
>  {
>  	struct aspeed_kcs_bmc *priv = to_aspeed_kcs_bmc(kcs_bmc);
> 
> -	switch (kcs_bmc->channel) {
> +	if (WARN_ON(nr_addrs < 1 || nr_addrs > 2))
> +		return -EINVAL;
> +
> +	switch (priv->kcs_bmc.channel) {
>  	case 1:
> -		regmap_update_bits(priv->map, LPC_HICR4,
> -				LPC_HICR4_LADR12AS, 0);
> -		regmap_write(priv->map, LPC_LADR12H, addr >> 8);
> -		regmap_write(priv->map, LPC_LADR12L, addr & 0xFF);
> +		regmap_update_bits(priv->map, LPC_HICR4, LPC_HICR4_LADR12AS,
> 0);
> +		regmap_write(priv->map, LPC_LADR12H, addrs[0] >> 8);
> +		regmap_write(priv->map, LPC_LADR12L, addrs[0] & 0xFF);
> +		if (nr_addrs == 2) {
> +			regmap_update_bits(priv->map, LPC_LSADR12,
> LPC_LSADR12_LSADR1_MASK,
> +					   addrs[1] << LPC_LSADR12_LSADR1_SHIFT);
> +
> +			regmap_update_bits(priv->map, LPC_HICRB,
> LPC_HICRB_EN16LADR1,
> +					   LPC_HICRB_EN16LADR1);
> +		}
>  		break;
> 
>  	case 2:
> -		regmap_update_bits(priv->map, LPC_HICR4,
> -				LPC_HICR4_LADR12AS, LPC_HICR4_LADR12AS);
> -		regmap_write(priv->map, LPC_LADR12H, addr >> 8);
> -		regmap_write(priv->map, LPC_LADR12L, addr & 0xFF);
> +		regmap_update_bits(priv->map, LPC_HICR4, LPC_HICR4_LADR12AS,
> LPC_HICR4_LADR12AS);
> +		regmap_write(priv->map, LPC_LADR12H, addrs[0] >> 8);
> +		regmap_write(priv->map, LPC_LADR12L, addrs[0] & 0xFF);
> +		if (nr_addrs == 2) {
> +			regmap_update_bits(priv->map, LPC_LSADR12,
> LPC_LSADR12_LSADR2_MASK,
> +					   addrs[1] << LPC_LSADR12_LSADR2_SHIFT);
> +
> +			regmap_update_bits(priv->map, LPC_HICRB,
> LPC_HICRB_EN16LADR2,
> +					   LPC_HICRB_EN16LADR2);
> +		}
>  		break;
> 
>  	case 3:
> -		regmap_write(priv->map, LPC_LADR3H, addr >> 8);
> -		regmap_write(priv->map, LPC_LADR3L, addr & 0xFF);
> +		if (nr_addrs == 2) {
> +			dev_err(priv->kcs_bmc.dev,
> +				"Channel 3 only supports inferred status IO address\n");
> +			return -EINVAL;
> +		}
> +
> +		regmap_write(priv->map, LPC_LADR3H, addrs[0] >> 8);
> +		regmap_write(priv->map, LPC_LADR3L, addrs[0] & 0xFF);
>  		break;
> 
>  	case 4:
> -		regmap_write(priv->map, LPC_LADR4, ((addr + 1) << 16) |
> -			addr);
> +		if (nr_addrs == 1)
> +			regmap_write(priv->map, LPC_LADR4, ((addrs[0] + 1) << 16) |
> addrs[0]);
> +		else
> +			regmap_write(priv->map, LPC_LADR4, (addrs[1] << 16) |
> addrs[0]);
> +
>  		break;
> 
>  	default:
> -		break;
> +		return -EINVAL;
>  	}
> +
> +	return 0;
>  }
> 
>  static inline int aspeed_kcs_map_serirq_type(u32 dt_type) @@ -462,18
> +495,18 @@ static int aspeed_kcs_of_v1_get_channel(struct platform_device
> *pdev)
>  	return channel;
>  }
> 
> -static int aspeed_kcs_of_v1_get_io_address(struct platform_device *pdev)
> +static int
> +aspeed_kcs_of_v1_get_io_address(struct platform_device *pdev, u32
> +addrs[2])
>  {
> -	u32 slave;
>  	int rc;
> 
> -	rc = of_property_read_u32(pdev->dev.of_node, "kcs_addr", &slave);
> -	if (rc || slave > 0xffff) {
> +	rc = of_property_read_u32(pdev->dev.of_node, "kcs_addr", addrs);
> +	if (rc || addrs[0] > 0xffff) {
>  		dev_err(&pdev->dev, "no valid 'kcs_addr' configured\n");
>  		return -EINVAL;
>  	}
> 
> -	return slave;
> +	return 1;
>  }
> 
>  static int aspeed_kcs_of_v2_get_channel(struct platform_device *pdev) @@
> -509,16 +542,27 @@ static int aspeed_kcs_of_v2_get_channel(struct
> platform_device *pdev)
>  	return -EINVAL;
>  }
> 
> -static int aspeed_kcs_of_v2_get_io_address(struct platform_device *pdev)
> +static int
> +aspeed_kcs_of_v2_get_io_address(struct platform_device *pdev, u32
> +addrs[2])
>  {
> -	uint32_t slave;
>  	int rc;
> 
> -	rc = of_property_read_u32(pdev->dev.of_node, "aspeed,lpc-io-reg",
> &slave);
> -	if (rc || slave > 0xffff)
> +	rc = of_property_read_variable_u32_array(pdev->dev.of_node,
> +						 "aspeed,lpc-io-reg",
> +						 addrs, 1, 2);
> +	if (rc < 0)
> +		return rc;
> +
> +	if (WARN_ON(rc == 0))
> +		return -EINVAL;
> +
> +	if (addrs[0] > 0xffff)
> +		return -EINVAL;
> +
> +	if (rc == 2 && addrs[1] > 0xffff)
>  		return -EINVAL;
> 
> -	return slave;
> +	return rc;
>  }
> 
>  static int aspeed_kcs_probe(struct platform_device *pdev) @@ -527,9
> +571,11 @@ static int aspeed_kcs_probe(struct platform_device *pdev)
>  	struct kcs_bmc_device *kcs_bmc;
>  	struct aspeed_kcs_bmc *priv;
>  	struct device_node *np;
> -	int rc, channel, addr;
>  	bool have_upstream_irq;
>  	u32 upstream_irq[2];
> +	int rc, channel;
> +	int nr_addrs;
> +	u32 addrs[2];
> 
>  	np = pdev->dev.of_node->parent;
>  	if (!of_device_is_compatible(np, "aspeed,ast2400-lpc-v2") && @@ -547,9
> +593,9 @@ static int aspeed_kcs_probe(struct platform_device *pdev)
>  	if (channel < 0)
>  		return channel;
> 
> -	addr = ops->get_io_address(pdev);
> -	if (addr < 0)
> -		return addr;
> +	nr_addrs = ops->get_io_address(pdev, addrs);
> +	if (nr_addrs < 0)
> +		return nr_addrs;
> 
>  	np = pdev->dev.of_node;
>  	rc = of_property_read_u32_array(np, "aspeed,lpc-interrupts",
> upstream_irq, 2); @@ -578,7 +624,9 @@ static int aspeed_kcs_probe(struct
> platform_device *pdev)
>  	priv->obe.remove = false;
>  	timer_setup(&priv->obe.timer, aspeed_kcs_check_obe, 0);
> 
> -	aspeed_kcs_set_address(kcs_bmc, addr);
> +	rc = aspeed_kcs_set_address(kcs_bmc, addrs, nr_addrs);
> +	if (rc)
> +		return rc;
> 
>  	/* Host to BMC IRQ */
>  	rc = aspeed_kcs_config_downstream_irq(kcs_bmc, pdev); @@ -600,7
> +648,8 @@ static int aspeed_kcs_probe(struct platform_device *pdev)
>  	if (rc < 0)
>  		return rc;
> 
> -	dev_info(&pdev->dev, "Initialised channel %d at 0x%x\n",
> kcs_bmc->channel, addr);
> +	dev_info(&pdev->dev, "Initialised channel %d at 0x%x\n",
> +			kcs_bmc->channel, addrs[0]);
> 
>  	return 0;
>  }
> --
> 2.27.0