diff mbox series

[v2,05/10] mtd: rawnand: brcmnand: Add BCMBCA read data bus interface

Message ID 20240118195356.133391-6-dregan@broadcom.com
State New
Headers show
Series mtd: rawnand: brcmnand: driver and doc updates | expand

Commit Message

David Regan Jan. 18, 2024, 7:53 p.m. UTC 
From: William Zhang <william.zhang@broadcom.com>

The BCMBCA broadband SoC integrates the NAND controller differently than
STB, iProc and other SoCs.  It has different endianness for NAND cache
data.

Add a SoC read data bus shim for BCMBCA to meet the specific SoC need
and performance improvement using the optimized memcpy function on NAND
cache memory.

Signed-off-by: William Zhang <william.zhang@broadcom.com>
Reviewed-by: David Regan <dregan@broadcom.com>
---
Changes in v2:
- Drop the is_param argument to the read data bus function now that we
have the exec_op API to read the parameter page and ONFI data
- Remove be32_to_cpu from brcmnand_read_data_bus
---
 drivers/mtd/nand/raw/brcmnand/bcmbca_nand.c | 27 +++++++++++++++++++++
 drivers/mtd/nand/raw/brcmnand/brcmnand.c    | 20 ++++++++++++---
 drivers/mtd/nand/raw/brcmnand/brcmnand.h    |  2 ++
 3 files changed, 46 insertions(+), 3 deletions(-)

Comments

Dan Carpenter Jan. 19, 2024, 5:36 a.m. UTC | #1 
On Thu, Jan 18, 2024 at 11:53:51AM -0800, dregan@broadcom.com wrote:
> diff --git a/drivers/mtd/nand/raw/brcmnand/bcmbca_nand.c b/drivers/mtd/nand/raw/brcmnand/bcmbca_nand.c
> index 3e2f3b79788d..e97e13ae246c 100644
> --- a/drivers/mtd/nand/raw/brcmnand/bcmbca_nand.c
> +++ b/drivers/mtd/nand/raw/brcmnand/bcmbca_nand.c
> @@ -26,6 +26,18 @@ enum {
>  	BCMBCA_CTLRDY		= BIT(4),
>  };
>  
> +#if defined(CONFIG_ARM64)
> +#define ALIGN_REQ		8
> +#else
> +#define ALIGN_REQ		4
> +#endif
> +
> +static inline bool bcmbca_nand_is_buf_aligned(void *flash_cache,  void *buffer)
> +{
> +	return IS_ALIGNED((uintptr_t)buffer, ALIGN_REQ) &&
> +				IS_ALIGNED((uintptr_t)flash_cache, ALIGN_REQ);
> +}
> +
>  static bool bcmbca_nand_intc_ack(struct brcmnand_soc *soc)
>  {
>  	struct bcmbca_nand_soc *priv =
> @@ -56,6 +68,20 @@ static void bcmbca_nand_intc_set(struct brcmnand_soc *soc, bool en)
>  	brcmnand_writel(val, mmio);
>  }
>  
> +static void bcmbca_read_data_bus(struct brcmnand_soc *soc,
> +				 void __iomem *flash_cache,  u32 *buffer, int fc_words)
> +{
> +	/*
> +	 * memcpy can do unaligned aligned access depending on source
> +	 * and dest address, which is incompatible with nand cache. Fallback
> +	 * to the memcpy for io version
> +	 */
> +	if (bcmbca_nand_is_buf_aligned((void *)flash_cache, buffer))
> +		memcpy((void *)buffer, (void *)flash_cache, fc_words * 4);
> +	else
> +		memcpy_fromio((void *)buffer, flash_cache, fc_words * 4);
> +}

This comment is confusing or maybe the if statement is reversed...
We're falling back to memcpy_fromio() for the unaligned accesses but the
comment says we're falling back to memcpy().

regards,
dan carpenter
William Zhang Jan. 19, 2024, 6:04 p.m. UTC | #2 
Hi,

On 01/18/2024 09:36 PM, Dan Carpenter wrote:
> On Thu, Jan 18, 2024 at 11:53:51AM -0800, dregan@broadcom.com wrote:
>> diff --git a/drivers/mtd/nand/raw/brcmnand/bcmbca_nand.c b/drivers/mtd/nand/raw/brcmnand/bcmbca_nand.c
>> index 3e2f3b79788d..e97e13ae246c 100644
>> --- a/drivers/mtd/nand/raw/brcmnand/bcmbca_nand.c
>> +++ b/drivers/mtd/nand/raw/brcmnand/bcmbca_nand.c
>> @@ -26,6 +26,18 @@ enum {
>>   	BCMBCA_CTLRDY		= BIT(4),
>>   };
>>   
>> +#if defined(CONFIG_ARM64)
>> +#define ALIGN_REQ		8
>> +#else
>> +#define ALIGN_REQ		4
>> +#endif
>> +
>> +static inline bool bcmbca_nand_is_buf_aligned(void *flash_cache,  void *buffer)
>> +{
>> +	return IS_ALIGNED((uintptr_t)buffer, ALIGN_REQ) &&
>> +				IS_ALIGNED((uintptr_t)flash_cache, ALIGN_REQ);
>> +}
>> +
>>   static bool bcmbca_nand_intc_ack(struct brcmnand_soc *soc)
>>   {
>>   	struct bcmbca_nand_soc *priv =
>> @@ -56,6 +68,20 @@ static void bcmbca_nand_intc_set(struct brcmnand_soc *soc, bool en)
>>   	brcmnand_writel(val, mmio);
>>   }
>>   
>> +static void bcmbca_read_data_bus(struct brcmnand_soc *soc,
>> +				 void __iomem *flash_cache,  u32 *buffer, int fc_words)
>> +{
>> +	/*
>> +	 * memcpy can do unaligned aligned access depending on source
>> +	 * and dest address, which is incompatible with nand cache. Fallback
>> +	 * to the memcpy for io version
>> +	 */
>> +	if (bcmbca_nand_is_buf_aligned((void *)flash_cache, buffer))
>> +		memcpy((void *)buffer, (void *)flash_cache, fc_words * 4);
>> +	else
>> +		memcpy_fromio((void *)buffer, flash_cache, fc_words * 4);
>> +}
> 
> This comment is confusing or maybe the if statement is reversed...
> We're falling back to memcpy_fromio() for the unaligned accesses but the
> comment says we're falling back to memcpy().
> 
Yes that's a typo. Fallback to memcpy_fromio when unalgined.  Will 
update the comments in v3. Thanks!

> regards,
> dan carpenter
>
diff mbox series

Patch

diff --git a/drivers/mtd/nand/raw/brcmnand/bcmbca_nand.c b/drivers/mtd/nand/raw/brcmnand/bcmbca_nand.c
index 3e2f3b79788d..e97e13ae246c 100644
--- a/drivers/mtd/nand/raw/brcmnand/bcmbca_nand.c
+++ b/drivers/mtd/nand/raw/brcmnand/bcmbca_nand.c
@@ -26,6 +26,18 @@  enum {
 	BCMBCA_CTLRDY		= BIT(4),
 };
 
+#if defined(CONFIG_ARM64)
+#define ALIGN_REQ		8
+#else
+#define ALIGN_REQ		4
+#endif
+
+static inline bool bcmbca_nand_is_buf_aligned(void *flash_cache,  void *buffer)
+{
+	return IS_ALIGNED((uintptr_t)buffer, ALIGN_REQ) &&
+				IS_ALIGNED((uintptr_t)flash_cache, ALIGN_REQ);
+}
+
 static bool bcmbca_nand_intc_ack(struct brcmnand_soc *soc)
 {
 	struct bcmbca_nand_soc *priv =
@@ -56,6 +68,20 @@  static void bcmbca_nand_intc_set(struct brcmnand_soc *soc, bool en)
 	brcmnand_writel(val, mmio);
 }
 
+static void bcmbca_read_data_bus(struct brcmnand_soc *soc,
+				 void __iomem *flash_cache,  u32 *buffer, int fc_words)
+{
+	/*
+	 * memcpy can do unaligned aligned access depending on source
+	 * and dest address, which is incompatible with nand cache. Fallback
+	 * to the memcpy for io version
+	 */
+	if (bcmbca_nand_is_buf_aligned((void *)flash_cache, buffer))
+		memcpy((void *)buffer, (void *)flash_cache, fc_words * 4);
+	else
+		memcpy_fromio((void *)buffer, flash_cache, fc_words * 4);
+}
+
 static int bcmbca_nand_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -73,6 +99,7 @@  static int bcmbca_nand_probe(struct platform_device *pdev)
 
 	soc->ctlrdy_ack = bcmbca_nand_intc_ack;
 	soc->ctlrdy_set_enabled = bcmbca_nand_intc_set;
+	soc->read_data_bus = bcmbca_read_data_bus;
 
 	return brcmnand_probe(pdev, soc);
 }
diff --git a/drivers/mtd/nand/raw/brcmnand/brcmnand.c b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
index 8faca43ae1ff..73fdf7ce21aa 100644
--- a/drivers/mtd/nand/raw/brcmnand/brcmnand.c
+++ b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
@@ -851,6 +851,20 @@  static inline u32 edu_readl(struct brcmnand_controller *ctrl,
 	return brcmnand_readl(ctrl->edu_base + offs);
 }
 
+static inline void brcmnand_read_data_bus(struct brcmnand_controller *ctrl,
+					  void __iomem *flash_cache, u32 *buffer, int fc_words)
+{
+	struct brcmnand_soc *soc = ctrl->soc;
+	int i;
+
+	if (soc->read_data_bus) {
+		soc->read_data_bus(soc, flash_cache, buffer, fc_words);
+	} else {
+		for (i = 0; i < fc_words; i++)
+			buffer[i] = brcmnand_read_fc(ctrl, i);
+	}
+}
+
 static void brcmnand_clear_ecc_addr(struct brcmnand_controller *ctrl)
 {
 
@@ -1975,7 +1989,7 @@  static int brcmnand_read_by_pio(struct mtd_info *mtd, struct nand_chip *chip,
 {
 	struct brcmnand_host *host = nand_get_controller_data(chip);
 	struct brcmnand_controller *ctrl = host->ctrl;
-	int i, j, ret = 0;
+	int i, ret = 0;
 
 	brcmnand_clear_ecc_addr(ctrl);
 
@@ -1988,8 +2002,8 @@  static int brcmnand_read_by_pio(struct mtd_info *mtd, struct nand_chip *chip,
 		if (likely(buf)) {
 			brcmnand_soc_data_bus_prepare(ctrl->soc, false);
 
-			for (j = 0; j < FC_WORDS; j++, buf++)
-				*buf = brcmnand_read_fc(ctrl, j);
+			brcmnand_read_data_bus(ctrl, ctrl->nand_fc, buf, FC_WORDS);
+			buf += FC_WORDS;
 
 			brcmnand_soc_data_bus_unprepare(ctrl->soc, false);
 		}
diff --git a/drivers/mtd/nand/raw/brcmnand/brcmnand.h b/drivers/mtd/nand/raw/brcmnand/brcmnand.h
index 928114c0be5e..7261a69989fe 100644
--- a/drivers/mtd/nand/raw/brcmnand/brcmnand.h
+++ b/drivers/mtd/nand/raw/brcmnand/brcmnand.h
@@ -24,6 +24,8 @@  struct brcmnand_soc {
 	void (*ctlrdy_set_enabled)(struct brcmnand_soc *soc, bool en);
 	void (*prepare_data_bus)(struct brcmnand_soc *soc, bool prepare,
 				 bool is_param);
+	void (*read_data_bus)(struct brcmnand_soc *soc, void __iomem *flash_cache,
+				  u32 *buffer, int fc_words);
 	const struct brcmnand_io_ops *ops;
 };