PCI: endpoint: pci-epf-test: Simplify pci_epf_test_set_bar() loop

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.)

Link: https://lore.kernel.org/linux-pci/20240320113157.322695-5-cassel@kernel.org
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
This commit is contained in:
Niklas Cassel 2024-03-20 12:31:51 +01:00 committed by Krzysztof Wilczyński
parent 828e870431
commit e49eab944c
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@ -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);