| Message ID | 20250305-pcc_fixes_updates-v2-3-1b1822bc8746@arm.com (mailing list archive) |
|---|---|
| State | Handled Elsewhere, archived |
| Headers | show |
| Series | mailbox: pcc: Fixes and cleanup/refactoring | expand |
在 2025/3/6 0:38, Sudeep Holla 写道: > The Sparse static checker flags a type mismatch warning related to > endianness conversion: > > | warning: incorrect type in argument 1 (different base types) > | expected restricted __le32 const [usertype] *p > | got unsigned int * > > This is because an explicit endianness conversion (le32_to_cpu()) was > applied unnecessarily to a pcc_hdr.flags field that is already in > little-endian format. > > The PCC driver is only enabled on little-endian kernels due to its > dependency on ACPI and EFI, making the explicit conversion unnecessary. > > The redundant conversion occurs in pcc_chan_check_and_ack() for the > pcc_hdr.flags field. Drop this unnecessary endianness conversion of > pcc_hdr.flags. > > Also drop the redundant PCC_ACK_FLAG_MASK definition and use the > more appropriate and already defined PCC_CMD_COMPLETION_NOTIFY. > > Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> > --- > drivers/mailbox/pcc.c | 2 +- > include/acpi/pcc.h | 1 - > 2 files changed, 1 insertion(+), 2 deletions(-) > > diff --git a/drivers/mailbox/pcc.c b/drivers/mailbox/pcc.c > index 4c582fa2b8bf4c9a9368dba8220f567555dba963..42dd405482e407cf90e66917a46fb8e350e0eeaf 100644 > --- a/drivers/mailbox/pcc.c > +++ b/drivers/mailbox/pcc.c > @@ -292,7 +292,7 @@ static void check_and_ack(struct pcc_chan_info *pchan, struct mbox_chan *chan) > * > * The PCC master subspace channel clears chan_in_use to free channel. > */ > - if (le32_to_cpup(&pcc_hdr.flags) & PCC_ACK_FLAG_MASK) > + if (pcc_hdr.flags & PCC_CMD_COMPLETION_NOTIFY) > pcc_send_data(chan, NULL); > else > pcc_chan_reg_read_modify_write(&pchan->cmd_update); > diff --git a/include/acpi/pcc.h b/include/acpi/pcc.h > index 699c1a37b8e7846362bae35477eb5736be15d79e..d1e506f041c5a80857d4a025fa3c1803746ba4b9 100644 > --- a/include/acpi/pcc.h > +++ b/include/acpi/pcc.h > @@ -32,7 +32,6 @@ struct pcc_mbox_chan { > #define PCC_CMD_COMPLETION_NOTIFY BIT(0) > > #define MAX_PCC_SUBSPACES 256 > -#define PCC_ACK_FLAG_MASK 0x1 > > #ifdef CONFIG_PCC > extern struct pcc_mbox_chan * Acked-by: Huisong Li <lihuisong@huawei.com> >
On 3/5/25 11:38, Sudeep Holla wrote: > The Sparse static checker flags a type mismatch warning related to > endianness conversion: > > | warning: incorrect type in argument 1 (different base types) > | expected restricted __le32 const [usertype] *p > | got unsigned int * > > This is because an explicit endianness conversion (le32_to_cpu()) was > applied unnecessarily to a pcc_hdr.flags field that is already in > little-endian format. > > The PCC driver is only enabled on little-endian kernels due to its > dependency on ACPI and EFI, making the explicit conversion unnecessary. > > The redundant conversion occurs in pcc_chan_check_and_ack() for the > pcc_hdr.flags field. Drop this unnecessary endianness conversion of > pcc_hdr.flags. > > Also drop the redundant PCC_ACK_FLAG_MASK definition and use the > more appropriate and already defined PCC_CMD_COMPLETION_NOTIFY. > > Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> > --- > drivers/mailbox/pcc.c | 2 +- > include/acpi/pcc.h | 1 - > 2 files changed, 1 insertion(+), 2 deletions(-) > > diff --git a/drivers/mailbox/pcc.c b/drivers/mailbox/pcc.c > index 4c582fa2b8bf4c9a9368dba8220f567555dba963..42dd405482e407cf90e66917a46fb8e350e0eeaf 100644 > --- a/drivers/mailbox/pcc.c > +++ b/drivers/mailbox/pcc.c > @@ -292,7 +292,7 @@ static void check_and_ack(struct pcc_chan_info *pchan, struct mbox_chan *chan) > * > * The PCC master subspace channel clears chan_in_use to free channel. > */ > - if (le32_to_cpup(&pcc_hdr.flags) & PCC_ACK_FLAG_MASK) > + if (pcc_hdr.flags & PCC_CMD_COMPLETION_NOTIFY) > pcc_send_data(chan, NULL); > else > pcc_chan_reg_read_modify_write(&pchan->cmd_update); > diff --git a/include/acpi/pcc.h b/include/acpi/pcc.h > index 699c1a37b8e7846362bae35477eb5736be15d79e..d1e506f041c5a80857d4a025fa3c1803746ba4b9 100644 > --- a/include/acpi/pcc.h > +++ b/include/acpi/pcc.h > @@ -32,7 +32,6 @@ struct pcc_mbox_chan { > #define PCC_CMD_COMPLETION_NOTIFY BIT(0) > > #define MAX_PCC_SUBSPACES 256 > -#define PCC_ACK_FLAG_MASK 0x1 > > #ifdef CONFIG_PCC > extern struct pcc_mbox_chan * > Make sense. The endianess was due to this coming from a network driver and should not be here. tested-by: admiyo@os.amperecomputing.com
diff --git a/drivers/mailbox/pcc.c b/drivers/mailbox/pcc.c index 4c582fa2b8bf4c9a9368dba8220f567555dba963..42dd405482e407cf90e66917a46fb8e350e0eeaf 100644 --- a/drivers/mailbox/pcc.c +++ b/drivers/mailbox/pcc.c @@ -292,7 +292,7 @@ static void check_and_ack(struct pcc_chan_info *pchan, struct mbox_chan *chan) * * The PCC master subspace channel clears chan_in_use to free channel. */ - if (le32_to_cpup(&pcc_hdr.flags) & PCC_ACK_FLAG_MASK) + if (pcc_hdr.flags & PCC_CMD_COMPLETION_NOTIFY) pcc_send_data(chan, NULL); else pcc_chan_reg_read_modify_write(&pchan->cmd_update); diff --git a/include/acpi/pcc.h b/include/acpi/pcc.h index 699c1a37b8e7846362bae35477eb5736be15d79e..d1e506f041c5a80857d4a025fa3c1803746ba4b9 100644 --- a/include/acpi/pcc.h +++ b/include/acpi/pcc.h @@ -32,7 +32,6 @@ struct pcc_mbox_chan { #define PCC_CMD_COMPLETION_NOTIFY BIT(0) #define MAX_PCC_SUBSPACES 256 -#define PCC_ACK_FLAG_MASK 0x1 #ifdef CONFIG_PCC extern struct pcc_mbox_chan *
The Sparse static checker flags a type mismatch warning related to endianness conversion: | warning: incorrect type in argument 1 (different base types) | expected restricted __le32 const [usertype] *p | got unsigned int * This is because an explicit endianness conversion (le32_to_cpu()) was applied unnecessarily to a pcc_hdr.flags field that is already in little-endian format. The PCC driver is only enabled on little-endian kernels due to its dependency on ACPI and EFI, making the explicit conversion unnecessary. The redundant conversion occurs in pcc_chan_check_and_ack() for the pcc_hdr.flags field. Drop this unnecessary endianness conversion of pcc_hdr.flags. Also drop the redundant PCC_ACK_FLAG_MASK definition and use the more appropriate and already defined PCC_CMD_COMPLETION_NOTIFY. Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> --- drivers/mailbox/pcc.c | 2 +- include/acpi/pcc.h | 1 - 2 files changed, 1 insertion(+), 2 deletions(-)