diff mbox series

[XEN,v3,1/9] xen/ns16550: Remove unneeded truncation check in the DT init code

Message ID 20230208120529.22313-2-ayan.kumar.halder@amd.com (mailing list archive)
State Superseded
Headers show
Series Add support for 32 bit physical address | expand

Commit Message

Ayan Kumar Halder Feb. 8, 2023, 12:05 p.m. UTC 
In an earlier commit (7c1de0038895), "ns16550.io_size" was u32 and
"io_size" was u64. Thus, the ASSERT() was needed to check if the values
are the same.
However, in a later commit (c9f8e0aee507), "ns16550.io_size" was changed
to u64. Thus, the ASSERT() became redundant.

So, now as "io_size" and "uart->io_size" are both u64, there will be no
truncation. Thus, one can remove the ASSERT() and extra assignment.

Signed-off-by: Ayan Kumar Halder <ayan.kumar.halder@amd.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
---
Changes from :

v1 - 1. Updated commit message/title.
2. Added Rb. 

v2 - No change.

 xen/drivers/char/ns16550.c | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

Comments

Julien Grall Feb. 11, 2023, 8:55 a.m. UTC | #1 
Hi Ayan

On 08/02/2023 12:05, Ayan Kumar Halder wrote:
> In an earlier commit (7c1de0038895), "ns16550.io_size" was u32 and
> "io_size" was u64. Thus, the ASSERT() was needed to check if the values
> are the same.
> However, in a later commit (c9f8e0aee507), "ns16550.io_size" was changed
> to u64. Thus, the ASSERT() became redundant.
> 
> So, now as "io_size" and "uart->io_size" are both u64, there will be no
> truncation. Thus, one can remove the ASSERT() and extra assignment.
> 
> Signed-off-by: Ayan Kumar Halder <ayan.kumar.halder@amd.com>
> Reviewed-by: Jan Beulich <jbeulich@suse.com>

Acked-by: Julien Grall <jgrall@amazon.com>

Cheers,
diff mbox series

Patch

diff --git a/xen/drivers/char/ns16550.c b/xen/drivers/char/ns16550.c
index 4ce74b3cd3..092f6b9c4b 100644
--- a/xen/drivers/char/ns16550.c
+++ b/xen/drivers/char/ns16550.c
@@ -1747,7 +1747,6 @@  static int __init ns16550_uart_dt_init(struct dt_device_node *dev,
     struct ns16550 *uart;
     int res;
     u32 reg_shift, reg_width;
-    u64 io_size;
 
     uart = &ns16550_com[0];
 
@@ -1758,14 +1757,10 @@  static int __init ns16550_uart_dt_init(struct dt_device_node *dev,
     uart->parity    = UART_PARITY_NONE;
     uart->stop_bits = 1;
 
-    res = dt_device_get_address(dev, 0, &uart->io_base, &io_size);
+    res = dt_device_get_address(dev, 0, &uart->io_base, &uart->io_size);
     if ( res )
         return res;
 
-    uart->io_size = io_size;
-
-    ASSERT(uart->io_size == io_size); /* Detect truncation */
-
     res = dt_property_read_u32(dev, "reg-shift", &reg_shift);
     if ( !res )
         uart->reg_shift = 0;