diff mbox series

[v4,4/7] PCI: endpoint: pci-epf-test: Simplify pci_epf_test_set_bar() loop

Message ID 20240320113157.322695-5-cassel@kernel.org (mailing list archive)
State Accepted
Delegated to: Krzysztof WilczyƄski
Headers show
Series minor PCI endpoint cleanups | expand

Commit Message

Niklas Cassel March 20, 2024, 11:31 a.m. UTC
Simplify the loop in pci_epf_test_set_bar().
If we allocated memory for the BAR, we need to call set_bar() for that
BAR, if we did not allocated memory for that BAR, we need to skip.
It is as simple as that. This also matches the logic in
pci_epf_test_unbind().

A 64-bit BAR will still only be one allocation, with the BAR succeeding
the 64-bit BAR being null.

While at it, remove the misleading comment.
A EPC .set_bar() callback should never change the epf_bar->flags.
(E.g. to set a 64-bit BAR if we requested a 32-bit BAR.)

A .set_bar() callback should do what we request it to do.
If it can't satisfy the request, it should return an error.

If platform has a specific requirement, e.g. that a certain BAR has to
be a 64-bit BAR, then it should specify that by setting the .only_64bit
flag for that specific BAR in epc_features->bar[], such that
pci_epf_alloc_space() will return a epf_bar with the 64-bit flag set.
(Such that .set_bar() will receive a request to set a 64-bit BAR.)

Signed-off-by: Niklas Cassel <cassel@kernel.org>
---
 drivers/pci/endpoint/functions/pci-epf-test.c | 21 ++++---------------
 1 file changed, 4 insertions(+), 17 deletions(-)

Comments

Manivannan Sadhasivam March 22, 2024, 10:31 a.m. UTC | #1
On Wed, Mar 20, 2024 at 12:31:51PM +0100, Niklas Cassel wrote:
> Simplify the loop in pci_epf_test_set_bar().
> If we allocated memory for the BAR, we need to call set_bar() for that
> BAR, if we did not allocated memory for that BAR, we need to skip.
> It is as simple as that. This also matches the logic in
> pci_epf_test_unbind().
> 
> A 64-bit BAR will still only be one allocation, with the BAR succeeding
> the 64-bit BAR being null.
> 
> While at it, remove the misleading comment.
> A EPC .set_bar() callback should never change the epf_bar->flags.
> (E.g. to set a 64-bit BAR if we requested a 32-bit BAR.)
> 
> A .set_bar() callback should do what we request it to do.
> If it can't satisfy the request, it should return an error.
> 
> If platform has a specific requirement, e.g. that a certain BAR has to
> be a 64-bit BAR, then it should specify that by setting the .only_64bit
> flag for that specific BAR in epc_features->bar[], such that
> pci_epf_alloc_space() will return a epf_bar with the 64-bit flag set.
> (Such that .set_bar() will receive a request to set a 64-bit BAR.)
> 
> Signed-off-by: Niklas Cassel <cassel@kernel.org>

Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

- Mani

> ---
>  drivers/pci/endpoint/functions/pci-epf-test.c | 21 ++++---------------
>  1 file changed, 4 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c
> index 0a83a1901bb7..faf347216b6b 100644
> --- a/drivers/pci/endpoint/functions/pci-epf-test.c
> +++ b/drivers/pci/endpoint/functions/pci-epf-test.c
> @@ -709,31 +709,18 @@ static void pci_epf_test_unbind(struct pci_epf *epf)
>  
>  static int pci_epf_test_set_bar(struct pci_epf *epf)
>  {
> -	int bar, add;
> -	int ret;
> -	struct pci_epf_bar *epf_bar;
> +	int bar, ret;
>  	struct pci_epc *epc = epf->epc;
>  	struct device *dev = &epf->dev;
>  	struct pci_epf_test *epf_test = epf_get_drvdata(epf);
>  	enum pci_barno test_reg_bar = epf_test->test_reg_bar;
> -	const struct pci_epc_features *epc_features;
>  
> -	epc_features = epf_test->epc_features;
> -
> -	for (bar = 0; bar < PCI_STD_NUM_BARS; bar += add) {
> -		epf_bar = &epf->bar[bar];
> -		/*
> -		 * pci_epc_set_bar() sets PCI_BASE_ADDRESS_MEM_TYPE_64
> -		 * if the specific implementation required a 64-bit BAR,
> -		 * even if we only requested a 32-bit BAR.
> -		 */
> -		add = (epf_bar->flags & PCI_BASE_ADDRESS_MEM_TYPE_64) ? 2 : 1;
> -
> -		if (epc_features->bar[bar].type == BAR_RESERVED)
> +	for (bar = 0; bar < PCI_STD_NUM_BARS; bar++) {
> +		if (!epf_test->reg[bar])
>  			continue;
>  
>  		ret = pci_epc_set_bar(epc, epf->func_no, epf->vfunc_no,
> -				      epf_bar);
> +				      &epf->bar[bar]);
>  		if (ret) {
>  			pci_epf_free_space(epf, epf_test->reg[bar], bar,
>  					   PRIMARY_INTERFACE);
> -- 
> 2.44.0
>
diff mbox series

Patch

diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c
index 0a83a1901bb7..faf347216b6b 100644
--- a/drivers/pci/endpoint/functions/pci-epf-test.c
+++ b/drivers/pci/endpoint/functions/pci-epf-test.c
@@ -709,31 +709,18 @@  static void pci_epf_test_unbind(struct pci_epf *epf)
 
 static int pci_epf_test_set_bar(struct pci_epf *epf)
 {
-	int bar, add;
-	int ret;
-	struct pci_epf_bar *epf_bar;
+	int bar, ret;
 	struct pci_epc *epc = epf->epc;
 	struct device *dev = &epf->dev;
 	struct pci_epf_test *epf_test = epf_get_drvdata(epf);
 	enum pci_barno test_reg_bar = epf_test->test_reg_bar;
-	const struct pci_epc_features *epc_features;
 
-	epc_features = epf_test->epc_features;
-
-	for (bar = 0; bar < PCI_STD_NUM_BARS; bar += add) {
-		epf_bar = &epf->bar[bar];
-		/*
-		 * pci_epc_set_bar() sets PCI_BASE_ADDRESS_MEM_TYPE_64
-		 * if the specific implementation required a 64-bit BAR,
-		 * even if we only requested a 32-bit BAR.
-		 */
-		add = (epf_bar->flags & PCI_BASE_ADDRESS_MEM_TYPE_64) ? 2 : 1;
-
-		if (epc_features->bar[bar].type == BAR_RESERVED)
+	for (bar = 0; bar < PCI_STD_NUM_BARS; bar++) {
+		if (!epf_test->reg[bar])
 			continue;
 
 		ret = pci_epc_set_bar(epc, epf->func_no, epf->vfunc_no,
-				      epf_bar);
+				      &epf->bar[bar]);
 		if (ret) {
 			pci_epf_free_space(epf, epf_test->reg[bar], bar,
 					   PRIMARY_INTERFACE);