* [PATCH 0/3] Add helper methods i3c_master_writesl and i3c_master_readsl
@ 2025-06-20 16:54 Jorge Marques
2025-06-20 16:54 ` [PATCH 1/3] i3c: master: Add inline i3c_master_readsl and i3c_master_writesl Jorge Marques
` (2 more replies)
0 siblings, 3 replies; 10+ messages in thread
From: Jorge Marques @ 2025-06-20 16:54 UTC (permalink / raw)
To: Alexandre Belloni, Frank Li, Przemysław Gaj
Cc: linux-i3c, linux-kernel, Jorge Marques
The i3c abstraction excepts u8 buffers, but some controllers have a bus
width of 32-bits and don't support flagging valid bytes, so it is
required to read/write long words and to use memcpy on the remainder of
the number of bytes by 32-bits to not write/read outside the buffer
bounds.
Add two auxiliary methods to include/linux/i3c/master.h and use in the dw
and cdns i3c controller drivers. The adi controller driver will also use
these methods.
Related thread: https://lore.kernel.org/linux-i3c/aFNziEj7j31xy%2FmY@lizhi-Precision-Tower-5810/
Signed-off-by: Jorge Marques <jorge.marques@analog.com>
---
Jorge Marques (3):
i3c: master: Add inline i3c_master_readsl and i3c_master_writesl
i3c: master: cdns: Use i3c_master_writesl and i3c_master_readsl
i3c: master: dw: Use i3c_master_writesl and i3c_master_readsl
drivers/i3c/master/dw-i3c-master.c | 24 +++---------------------
drivers/i3c/master/i3c-master-cdns.c | 23 +++--------------------
include/linux/i3c/master.h | 36 ++++++++++++++++++++++++++++++++++++
3 files changed, 42 insertions(+), 41 deletions(-)
---
base-commit: 51963783b876a2f493a3eac0ea9eba271cb6809a
change-id: 20250620-i3c-writesl-readsl-e2836534b665
Best regards,
--
Jorge Marques <jorge.marques@analog.com>
--
linux-i3c mailing list
linux-i3c@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-i3c
^ permalink raw reply [flat|nested] 10+ messages in thread
* [PATCH 1/3] i3c: master: Add inline i3c_master_readsl and i3c_master_writesl
2025-06-20 16:54 [PATCH 0/3] Add helper methods i3c_master_writesl and i3c_master_readsl Jorge Marques
@ 2025-06-20 16:54 ` Jorge Marques
2025-06-20 18:41 ` Frank Li
2025-06-20 21:15 ` Wolfram Sang
2025-06-20 16:55 ` [PATCH 2/3] i3c: master: cdns: Use i3c_master_writesl and i3c_master_readsl Jorge Marques
2025-06-20 16:55 ` [PATCH 3/3] i3c: master: dw: " Jorge Marques
2 siblings, 2 replies; 10+ messages in thread
From: Jorge Marques @ 2025-06-20 16:54 UTC (permalink / raw)
To: Alexandre Belloni, Frank Li, Przemysław Gaj
Cc: linux-i3c, linux-kernel, Jorge Marques
The i3c abstraction excepts u8 buffers, but some controllers have a bus
width of 32-bits and don't support flagging valid bytes, so it is
required to read/write long words and to use memcpy on the remainder of
the number of bytes by 32-bits to not write/read outside the buffer
bounds.
Signed-off-by: Jorge Marques <jorge.marques@analog.com>
---
include/linux/i3c/master.h | 36 ++++++++++++++++++++++++++++++++++++
1 file changed, 36 insertions(+)
diff --git a/include/linux/i3c/master.h b/include/linux/i3c/master.h
index c67922ece617d6320c0c7e4838c2e7edda8c19f5..11401f2acb42e4d3a60df33b7c794d8a0360cdc2 100644
--- a/include/linux/i3c/master.h
+++ b/include/linux/i3c/master.h
@@ -674,6 +674,42 @@ i3c_master_get_bus(struct i3c_master_controller *master)
return &master->bus;
}
+/**
+ * i3c_master_writesl- Write bytes to long memory region from byte array
+ * @addr: Register to write to
+ * @bytes: Pointer to the data bytes to write
+ * @nbytes: Number of bytes to write
+ */
+static inline void i3c_master_writesl(void __iomem *addr, const u8 *bytes,
+ int nbytes)
+{
+writesl(addr, bytes, nbytes / 4);
+ if (nbytes & 3) {
+ u32 tmp = 0;
+
+ memcpy(&tmp, bytes + (nbytes & ~3), nbytes & 3);
+ writel(tmp, addr);
+ }
+}
+
+/**
+ * i3c_master_readsl - Read bytes from long memory region to byte array
+ * @addr: Register to read from
+ * @bytes: Pointer to the buffer to store read bytes
+ * @nbytes: Number of bytes to read
+ */
+static inline void i3c_master_readsl(const void __iomem *addr, u8 *bytes,
+ int nbytes)
+{
+readsl(addr, bytes, nbytes / 4);
+ if (nbytes & 3) {
+ u32 tmp;
+
+ tmp = readl(addr);
+ memcpy(bytes + (nbytes & ~3), &tmp, nbytes & 3);
+ }
+}
+
struct i3c_generic_ibi_pool;
struct i3c_generic_ibi_pool *
--
2.49.0
--
linux-i3c mailing list
linux-i3c@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-i3c
^ permalink raw reply related [flat|nested] 10+ messages in thread
* [PATCH 2/3] i3c: master: cdns: Use i3c_master_writesl and i3c_master_readsl
2025-06-20 16:54 [PATCH 0/3] Add helper methods i3c_master_writesl and i3c_master_readsl Jorge Marques
2025-06-20 16:54 ` [PATCH 1/3] i3c: master: Add inline i3c_master_readsl and i3c_master_writesl Jorge Marques
@ 2025-06-20 16:55 ` Jorge Marques
2025-06-20 18:46 ` Frank Li
2025-06-20 16:55 ` [PATCH 3/3] i3c: master: dw: " Jorge Marques
2 siblings, 1 reply; 10+ messages in thread
From: Jorge Marques @ 2025-06-20 16:55 UTC (permalink / raw)
To: Alexandre Belloni, Frank Li, Przemysław Gaj
Cc: linux-i3c, linux-kernel, Jorge Marques
Use the inline write/read methods common to controllers that have a
bus width of 32-bits.
Signed-off-by: Jorge Marques <jorge.marques@analog.com>
---
drivers/i3c/master/i3c-master-cdns.c | 23 +++--------------------
1 file changed, 3 insertions(+), 20 deletions(-)
diff --git a/drivers/i3c/master/i3c-master-cdns.c b/drivers/i3c/master/i3c-master-cdns.c
index fd3752cea654954ed1e37337754e45fddbbbf68e..6775751144ae86c1795abf45ceede17e1961bb74 100644
--- a/drivers/i3c/master/i3c-master-cdns.c
+++ b/drivers/i3c/master/i3c-master-cdns.c
@@ -427,25 +427,13 @@ to_cdns_i3c_master(struct i3c_master_controller *master)
static void cdns_i3c_master_wr_to_tx_fifo(struct cdns_i3c_master *master,
const u8 *bytes, int nbytes)
{
- writesl(master->regs + TX_FIFO, bytes, nbytes / 4);
- if (nbytes & 3) {
- u32 tmp = 0;
-
- memcpy(&tmp, bytes + (nbytes & ~3), nbytes & 3);
- writesl(master->regs + TX_FIFO, &tmp, 1);
- }
+ i3c_master_writesl(master->regs + TX_FIFO, bytes, nbytes);
}
static void cdns_i3c_master_rd_from_rx_fifo(struct cdns_i3c_master *master,
u8 *bytes, int nbytes)
{
- readsl(master->regs + RX_FIFO, bytes, nbytes / 4);
- if (nbytes & 3) {
- u32 tmp;
-
- readsl(master->regs + RX_FIFO, &tmp, 1);
- memcpy(bytes + (nbytes & ~3), &tmp, nbytes & 3);
- }
+ i3c_master_readsl(master->regs + RX_FIFO, bytes, nbytes);
}
static bool cdns_i3c_master_supports_ccc_cmd(struct i3c_master_controller *m,
@@ -1330,12 +1318,7 @@ static void cdns_i3c_master_handle_ibi(struct cdns_i3c_master *master,
buf = slot->data;
nbytes = IBIR_XFER_BYTES(ibir);
- readsl(master->regs + IBI_DATA_FIFO, buf, nbytes / 4);
- if (nbytes % 3) {
- u32 tmp = __raw_readl(master->regs + IBI_DATA_FIFO);
-
- memcpy(buf + (nbytes & ~3), &tmp, nbytes & 3);
- }
+ i3c_master_readsl(master->regs + IBI_DATA_FIFO, buf, nbytes);
slot->len = min_t(unsigned int, IBIR_XFER_BYTES(ibir),
dev->ibi->max_payload_len);
--
2.49.0
--
linux-i3c mailing list
linux-i3c@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-i3c
^ permalink raw reply related [flat|nested] 10+ messages in thread
* [PATCH 3/3] i3c: master: dw: Use i3c_master_writesl and i3c_master_readsl
2025-06-20 16:54 [PATCH 0/3] Add helper methods i3c_master_writesl and i3c_master_readsl Jorge Marques
2025-06-20 16:54 ` [PATCH 1/3] i3c: master: Add inline i3c_master_readsl and i3c_master_writesl Jorge Marques
2025-06-20 16:55 ` [PATCH 2/3] i3c: master: cdns: Use i3c_master_writesl and i3c_master_readsl Jorge Marques
@ 2025-06-20 16:55 ` Jorge Marques
2025-06-20 18:48 ` Frank Li
2 siblings, 1 reply; 10+ messages in thread
From: Jorge Marques @ 2025-06-20 16:55 UTC (permalink / raw)
To: Alexandre Belloni, Frank Li, Przemysław Gaj
Cc: linux-i3c, linux-kernel, Jorge Marques
Use the inline write/read methods common to controllers that have a
bus width of 32-bits.
Signed-off-by: Jorge Marques <jorge.marques@analog.com>
---
drivers/i3c/master/dw-i3c-master.c | 24 +++---------------------
1 file changed, 3 insertions(+), 21 deletions(-)
diff --git a/drivers/i3c/master/dw-i3c-master.c b/drivers/i3c/master/dw-i3c-master.c
index 611c22b72c1572ddf717c8ad473e44a3b8fcceaf..eb1346409829dc64cdd1d738e9870993d38bbb0f 100644
--- a/drivers/i3c/master/dw-i3c-master.c
+++ b/drivers/i3c/master/dw-i3c-master.c
@@ -336,37 +336,19 @@ static int dw_i3c_master_get_free_pos(struct dw_i3c_master *master)
static void dw_i3c_master_wr_tx_fifo(struct dw_i3c_master *master,
const u8 *bytes, int nbytes)
{
- writesl(master->regs + RX_TX_DATA_PORT, bytes, nbytes / 4);
- if (nbytes & 3) {
- u32 tmp = 0;
-
- memcpy(&tmp, bytes + (nbytes & ~3), nbytes & 3);
- writesl(master->regs + RX_TX_DATA_PORT, &tmp, 1);
- }
-}
-
-static void dw_i3c_master_read_fifo(struct dw_i3c_master *master,
- int reg, u8 *bytes, int nbytes)
-{
- readsl(master->regs + reg, bytes, nbytes / 4);
- if (nbytes & 3) {
- u32 tmp;
-
- readsl(master->regs + reg, &tmp, 1);
- memcpy(bytes + (nbytes & ~3), &tmp, nbytes & 3);
- }
+ i3c_master_writesl(master->regs + RX_TX_DATA_PORT, bytes, nbytes);
}
static void dw_i3c_master_read_rx_fifo(struct dw_i3c_master *master,
u8 *bytes, int nbytes)
{
- return dw_i3c_master_read_fifo(master, RX_TX_DATA_PORT, bytes, nbytes);
+ i3c_master_readsl(master + RX_TX_DATA_PORT, bytes, nbytes);
}
static void dw_i3c_master_read_ibi_fifo(struct dw_i3c_master *master,
u8 *bytes, int nbytes)
{
- return dw_i3c_master_read_fifo(master, IBI_QUEUE_STATUS, bytes, nbytes);
+ i3c_master_readsl(master + IBI_QUEUE_STATUS, bytes, nbytes);
}
static struct dw_i3c_xfer *
--
2.49.0
--
linux-i3c mailing list
linux-i3c@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-i3c
^ permalink raw reply related [flat|nested] 10+ messages in thread
* Re: [PATCH 1/3] i3c: master: Add inline i3c_master_readsl and i3c_master_writesl
2025-06-20 16:54 ` [PATCH 1/3] i3c: master: Add inline i3c_master_readsl and i3c_master_writesl Jorge Marques
@ 2025-06-20 18:41 ` Frank Li
2025-06-22 8:43 ` Jorge Marques
2025-06-20 21:15 ` Wolfram Sang
1 sibling, 1 reply; 10+ messages in thread
From: Frank Li @ 2025-06-20 18:41 UTC (permalink / raw)
To: Jorge Marques
Cc: Alexandre Belloni, Przemysław Gaj, linux-i3c, linux-kernel
On Fri, Jun 20, 2025 at 06:54:59PM +0200, Jorge Marques wrote:
> The i3c abstraction excepts u8 buffers, but some controllers have a bus
> width of 32-bits and don't support flagging valid bytes, so it is
> required to read/write long words and to use memcpy on the remainder of
> the number of bytes by 32-bits to not write/read outside the buffer
> bounds.
>
> Signed-off-by: Jorge Marques <jorge.marques@analog.com>
> ---
> include/linux/i3c/master.h | 36 ++++++++++++++++++++++++++++++++++++
> 1 file changed, 36 insertions(+)
>
> diff --git a/include/linux/i3c/master.h b/include/linux/i3c/master.h
> index c67922ece617d6320c0c7e4838c2e7edda8c19f5..11401f2acb42e4d3a60df33b7c794d8a0360cdc2 100644
> --- a/include/linux/i3c/master.h
> +++ b/include/linux/i3c/master.h
suggest move to drivers/i3c/internals.h becaue only master drivers use it.
> @@ -674,6 +674,42 @@ i3c_master_get_bus(struct i3c_master_controller *master)
> return &master->bus;
> }
>
> +/**
> + * i3c_master_writesl- Write bytes to long memory region from byte array
> + * @addr: Register to write to
> + * @bytes: Pointer to the data bytes to write
> + * @nbytes: Number of bytes to write
> + */
> +static inline void i3c_master_writesl(void __iomem *addr, const u8 *bytes,
> + int nbytes)
const void *bytes
> +{
> +writesl(addr, bytes, nbytes / 4);
fix indention
Frank
> + if (nbytes & 3) {
> + u32 tmp = 0;
> +
> + memcpy(&tmp, bytes + (nbytes & ~3), nbytes & 3);
> + writel(tmp, addr);
> + }
> +}
> +
> +/**
> + * i3c_master_readsl - Read bytes from long memory region to byte array
> + * @addr: Register to read from
> + * @bytes: Pointer to the buffer to store read bytes
> + * @nbytes: Number of bytes to read
> + */
> +static inline void i3c_master_readsl(const void __iomem *addr, u8 *bytes,
> + int nbytes)
> +{
> +readsl(addr, bytes, nbytes / 4);
> + if (nbytes & 3) {
> + u32 tmp;
> +
> + tmp = readl(addr);
> + memcpy(bytes + (nbytes & ~3), &tmp, nbytes & 3);
> + }
> +}
> +
> struct i3c_generic_ibi_pool;
>
> struct i3c_generic_ibi_pool *
>
> --
> 2.49.0
>
>
--
linux-i3c mailing list
linux-i3c@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-i3c
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH 2/3] i3c: master: cdns: Use i3c_master_writesl and i3c_master_readsl
2025-06-20 16:55 ` [PATCH 2/3] i3c: master: cdns: Use i3c_master_writesl and i3c_master_readsl Jorge Marques
@ 2025-06-20 18:46 ` Frank Li
0 siblings, 0 replies; 10+ messages in thread
From: Frank Li @ 2025-06-20 18:46 UTC (permalink / raw)
To: Jorge Marques
Cc: Alexandre Belloni, Przemysław Gaj, linux-i3c, linux-kernel
On Fri, Jun 20, 2025 at 06:55:00PM +0200, Jorge Marques wrote:
> Use the inline write/read methods common to controllers that have a
> bus width of 32-bits.
Subject function need add "()".
i3c: master: cdns: Use i3c_master_writesl() and i3c_master_readsl()
Use common inline i3c_master_writesl()/i3c_master_readsl() methods to
simplify code since the FIFO of controller is a 32bit width.
Frank
>
> Signed-off-by: Jorge Marques <jorge.marques@analog.com>
> ---
> drivers/i3c/master/i3c-master-cdns.c | 23 +++--------------------
> 1 file changed, 3 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/i3c/master/i3c-master-cdns.c b/drivers/i3c/master/i3c-master-cdns.c
> index fd3752cea654954ed1e37337754e45fddbbbf68e..6775751144ae86c1795abf45ceede17e1961bb74 100644
> --- a/drivers/i3c/master/i3c-master-cdns.c
> +++ b/drivers/i3c/master/i3c-master-cdns.c
> @@ -427,25 +427,13 @@ to_cdns_i3c_master(struct i3c_master_controller *master)
> static void cdns_i3c_master_wr_to_tx_fifo(struct cdns_i3c_master *master,
> const u8 *bytes, int nbytes)
> {
> - writesl(master->regs + TX_FIFO, bytes, nbytes / 4);
> - if (nbytes & 3) {
> - u32 tmp = 0;
> -
> - memcpy(&tmp, bytes + (nbytes & ~3), nbytes & 3);
> - writesl(master->regs + TX_FIFO, &tmp, 1);
> - }
> + i3c_master_writesl(master->regs + TX_FIFO, bytes, nbytes);
> }
>
> static void cdns_i3c_master_rd_from_rx_fifo(struct cdns_i3c_master *master,
> u8 *bytes, int nbytes)
> {
> - readsl(master->regs + RX_FIFO, bytes, nbytes / 4);
> - if (nbytes & 3) {
> - u32 tmp;
> -
> - readsl(master->regs + RX_FIFO, &tmp, 1);
> - memcpy(bytes + (nbytes & ~3), &tmp, nbytes & 3);
> - }
> + i3c_master_readsl(master->regs + RX_FIFO, bytes, nbytes);
> }
>
> static bool cdns_i3c_master_supports_ccc_cmd(struct i3c_master_controller *m,
> @@ -1330,12 +1318,7 @@ static void cdns_i3c_master_handle_ibi(struct cdns_i3c_master *master,
> buf = slot->data;
>
> nbytes = IBIR_XFER_BYTES(ibir);
> - readsl(master->regs + IBI_DATA_FIFO, buf, nbytes / 4);
> - if (nbytes % 3) {
> - u32 tmp = __raw_readl(master->regs + IBI_DATA_FIFO);
> -
> - memcpy(buf + (nbytes & ~3), &tmp, nbytes & 3);
> - }
> + i3c_master_readsl(master->regs + IBI_DATA_FIFO, buf, nbytes);
>
> slot->len = min_t(unsigned int, IBIR_XFER_BYTES(ibir),
> dev->ibi->max_payload_len);
>
> --
> 2.49.0
>
>
--
linux-i3c mailing list
linux-i3c@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-i3c
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH 3/3] i3c: master: dw: Use i3c_master_writesl and i3c_master_readsl
2025-06-20 16:55 ` [PATCH 3/3] i3c: master: dw: " Jorge Marques
@ 2025-06-20 18:48 ` Frank Li
0 siblings, 0 replies; 10+ messages in thread
From: Frank Li @ 2025-06-20 18:48 UTC (permalink / raw)
To: Jorge Marques
Cc: Alexandre Belloni, Przemysław Gaj, linux-i3c, linux-kernel
On Fri, Jun 20, 2025 at 06:55:01PM +0200, Jorge Marques wrote:
> Use the inline write/read methods common to controllers that have a
> bus width of 32-bits.
please update commit message and subject according to previous patch's
comments.
Frank
>
> Signed-off-by: Jorge Marques <jorge.marques@analog.com>
> ---
> drivers/i3c/master/dw-i3c-master.c | 24 +++---------------------
> 1 file changed, 3 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/i3c/master/dw-i3c-master.c b/drivers/i3c/master/dw-i3c-master.c
> index 611c22b72c1572ddf717c8ad473e44a3b8fcceaf..eb1346409829dc64cdd1d738e9870993d38bbb0f 100644
> --- a/drivers/i3c/master/dw-i3c-master.c
> +++ b/drivers/i3c/master/dw-i3c-master.c
> @@ -336,37 +336,19 @@ static int dw_i3c_master_get_free_pos(struct dw_i3c_master *master)
> static void dw_i3c_master_wr_tx_fifo(struct dw_i3c_master *master,
> const u8 *bytes, int nbytes)
> {
> - writesl(master->regs + RX_TX_DATA_PORT, bytes, nbytes / 4);
> - if (nbytes & 3) {
> - u32 tmp = 0;
> -
> - memcpy(&tmp, bytes + (nbytes & ~3), nbytes & 3);
> - writesl(master->regs + RX_TX_DATA_PORT, &tmp, 1);
> - }
> -}
> -
> -static void dw_i3c_master_read_fifo(struct dw_i3c_master *master,
> - int reg, u8 *bytes, int nbytes)
> -{
> - readsl(master->regs + reg, bytes, nbytes / 4);
> - if (nbytes & 3) {
> - u32 tmp;
> -
> - readsl(master->regs + reg, &tmp, 1);
> - memcpy(bytes + (nbytes & ~3), &tmp, nbytes & 3);
> - }
> + i3c_master_writesl(master->regs + RX_TX_DATA_PORT, bytes, nbytes);
> }
>
> static void dw_i3c_master_read_rx_fifo(struct dw_i3c_master *master,
> u8 *bytes, int nbytes)
> {
> - return dw_i3c_master_read_fifo(master, RX_TX_DATA_PORT, bytes, nbytes);
> + i3c_master_readsl(master + RX_TX_DATA_PORT, bytes, nbytes);
> }
>
> static void dw_i3c_master_read_ibi_fifo(struct dw_i3c_master *master,
> u8 *bytes, int nbytes)
> {
> - return dw_i3c_master_read_fifo(master, IBI_QUEUE_STATUS, bytes, nbytes);
> + i3c_master_readsl(master + IBI_QUEUE_STATUS, bytes, nbytes);
> }
>
> static struct dw_i3c_xfer *
>
> --
> 2.49.0
>
>
--
linux-i3c mailing list
linux-i3c@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-i3c
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH 1/3] i3c: master: Add inline i3c_master_readsl and i3c_master_writesl
2025-06-20 16:54 ` [PATCH 1/3] i3c: master: Add inline i3c_master_readsl and i3c_master_writesl Jorge Marques
2025-06-20 18:41 ` Frank Li
@ 2025-06-20 21:15 ` Wolfram Sang
2025-06-22 8:31 ` Jorge Marques
1 sibling, 1 reply; 10+ messages in thread
From: Wolfram Sang @ 2025-06-20 21:15 UTC (permalink / raw)
To: Jorge Marques
Cc: Alexandre Belloni, Frank Li, Przemysław Gaj, linux-i3c,
linux-kernel
[-- Attachment #1.1: Type: text/plain, Size: 657 bytes --]
On Fri, Jun 20, 2025 at 06:54:59PM +0200, Jorge Marques wrote:
> The i3c abstraction excepts u8 buffers, but some controllers have a bus
> width of 32-bits and don't support flagging valid bytes, so it is
> required to read/write long words and to use memcpy on the remainder of
> the number of bytes by 32-bits to not write/read outside the buffer
> bounds.
>
> Signed-off-by: Jorge Marques <jorge.marques@analog.com>
Suggested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
> + * i3c_master_writesl- Write bytes to long memory region from byte array
Frank proposed the name 'i3c_writel_fifo' which I like a tad better.
Opinions?
[-- Attachment #1.2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
[-- Attachment #2: Type: text/plain, Size: 111 bytes --]
--
linux-i3c mailing list
linux-i3c@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-i3c
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH 1/3] i3c: master: Add inline i3c_master_readsl and i3c_master_writesl
2025-06-20 21:15 ` Wolfram Sang
@ 2025-06-22 8:31 ` Jorge Marques
0 siblings, 0 replies; 10+ messages in thread
From: Jorge Marques @ 2025-06-22 8:31 UTC (permalink / raw)
To: Wolfram Sang
Cc: Jorge Marques, Alexandre Belloni, Frank Li, Przemysław Gaj,
linux-i3c, linux-kernel
On Fri, Jun 20, 2025 at 11:15:09PM +0200, Wolfram Sang wrote:
> On Fri, Jun 20, 2025 at 06:54:59PM +0200, Jorge Marques wrote:
> > The i3c abstraction excepts u8 buffers, but some controllers have a bus
> > width of 32-bits and don't support flagging valid bytes, so it is
> > required to read/write long words and to use memcpy on the remainder of
> > the number of bytes by 32-bits to not write/read outside the buffer
> > bounds.
> >
> > Signed-off-by: Jorge Marques <jorge.marques@analog.com>
>
> Suggested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
>
> > + * i3c_master_writesl- Write bytes to long memory region from byte array
>
Hi Wolfram,
> Frank proposed the name 'i3c_writel_fifo' which I like a tad better.
> Opinions?
>
I don't oppose the change and I'll rename, as well moving the method to
internals.h
i3c_master_writesl -> i3c_writel_fifo
i3c_master_readsl -> i3c_readl_fifo
Best Regards,
Jorge
--
linux-i3c mailing list
linux-i3c@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-i3c
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH 1/3] i3c: master: Add inline i3c_master_readsl and i3c_master_writesl
2025-06-20 18:41 ` Frank Li
@ 2025-06-22 8:43 ` Jorge Marques
0 siblings, 0 replies; 10+ messages in thread
From: Jorge Marques @ 2025-06-22 8:43 UTC (permalink / raw)
To: Frank Li
Cc: Jorge Marques, Alexandre Belloni, Przemysław Gaj, linux-i3c,
linux-kernel
On Fri, Jun 20, 2025 at 02:41:12PM -0400, Frank Li wrote:
> On Fri, Jun 20, 2025 at 06:54:59PM +0200, Jorge Marques wrote:
> > The i3c abstraction excepts u8 buffers, but some controllers have a bus
> > width of 32-bits and don't support flagging valid bytes, so it is
> > required to read/write long words and to use memcpy on the remainder of
> > the number of bytes by 32-bits to not write/read outside the buffer
> > bounds.
> >
> > Signed-off-by: Jorge Marques <jorge.marques@analog.com>
> > ---
> > include/linux/i3c/master.h | 36 ++++++++++++++++++++++++++++++++++++
> > 1 file changed, 36 insertions(+)
> >
> > diff --git a/include/linux/i3c/master.h b/include/linux/i3c/master.h
> > index c67922ece617d6320c0c7e4838c2e7edda8c19f5..11401f2acb42e4d3a60df33b7c794d8a0360cdc2 100644
> > --- a/include/linux/i3c/master.h
> > +++ b/include/linux/i3c/master.h
>
> suggest move to drivers/i3c/internals.h becaue only master drivers use it.
>
Hi Frank,
Ok, also renaming to i3c_writel_fifo() and i3c_readl_fifo() as well
reworking the commit messages.
> > @@ -674,6 +674,42 @@ i3c_master_get_bus(struct i3c_master_controller *master)
> > return &master->bus;
> > }
> >
> > +/**
> > + * i3c_master_writesl- Write bytes to long memory region from byte array
> > + * @addr: Register to write to
> > + * @bytes: Pointer to the data bytes to write
> > + * @nbytes: Number of bytes to write
> > + */
> > +static inline void i3c_master_writesl(void __iomem *addr, const u8 *bytes,
> > + int nbytes)
>
> const void *bytes
>
Ack.
> > +{
> > +writesl(addr, bytes, nbytes / 4);
>
> fix indention
>
> Frank
>
Ack.
Best regards,
Jorge
> > + if (nbytes & 3) {
> > + u32 tmp = 0;
> > +
> > + memcpy(&tmp, bytes + (nbytes & ~3), nbytes & 3);
> > + writel(tmp, addr);
> > + }
> > +}
> > +
> > +/**
> > + * i3c_master_readsl - Read bytes from long memory region to byte array
> > + * @addr: Register to read from
> > + * @bytes: Pointer to the buffer to store read bytes
> > + * @nbytes: Number of bytes to read
> > + */
> > +static inline void i3c_master_readsl(const void __iomem *addr, u8 *bytes,
> > + int nbytes)
> > +{
> > +readsl(addr, bytes, nbytes / 4);
> > + if (nbytes & 3) {
> > + u32 tmp;
> > +
> > + tmp = readl(addr);
> > + memcpy(bytes + (nbytes & ~3), &tmp, nbytes & 3);
> > + }
> > +}
> > +
> > struct i3c_generic_ibi_pool;
> >
> > struct i3c_generic_ibi_pool *
> >
> > --
> > 2.49.0
> >
> >
--
linux-i3c mailing list
linux-i3c@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-i3c
^ permalink raw reply [flat|nested] 10+ messages in thread
end of thread, other threads:[~2025-06-24 0:30 UTC | newest]
Thread overview: 10+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-06-20 16:54 [PATCH 0/3] Add helper methods i3c_master_writesl and i3c_master_readsl Jorge Marques
2025-06-20 16:54 ` [PATCH 1/3] i3c: master: Add inline i3c_master_readsl and i3c_master_writesl Jorge Marques
2025-06-20 18:41 ` Frank Li
2025-06-22 8:43 ` Jorge Marques
2025-06-20 21:15 ` Wolfram Sang
2025-06-22 8:31 ` Jorge Marques
2025-06-20 16:55 ` [PATCH 2/3] i3c: master: cdns: Use i3c_master_writesl and i3c_master_readsl Jorge Marques
2025-06-20 18:46 ` Frank Li
2025-06-20 16:55 ` [PATCH 3/3] i3c: master: dw: " Jorge Marques
2025-06-20 18:48 ` Frank Li
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).