[PATCH 2/7] PCI: epf-mhi: Make use of the alignment restriction from EPF core

From: Manivannan Sadhasivam
Date: Tue Jun 06 2023 - 07:58:51 EST


Instead of hardcoding the alignment restriction in the EPF_MHI driver, make
use of the info available from the EPF core that reflects the alignment
restriction of the endpoint controller.

For this purpose, let's introduce the get_align_offset() static function.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
---
drivers/pci/endpoint/functions/pci-epf-mhi.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/endpoint/functions/pci-epf-mhi.c b/drivers/pci/endpoint/functions/pci-epf-mhi.c
index 1227f059ea12..cef866f7d204 100644
--- a/drivers/pci/endpoint/functions/pci-epf-mhi.c
+++ b/drivers/pci/endpoint/functions/pci-epf-mhi.c
@@ -102,6 +102,11 @@ struct pci_epf_mhi {
int irq;
};

+static size_t get_align_offset(struct pci_epc *epc, u64 addr)
+{
+ return addr % epc->mem->window.page_size;
+}
+
static int __pci_epf_mhi_alloc_map(struct mhi_ep_cntrl *mhi_cntrl, u64 pci_addr,
phys_addr_t *paddr, void __iomem **vaddr,
size_t offset, size_t size)
@@ -134,7 +139,7 @@ static int pci_epf_mhi_alloc_map(struct mhi_ep_cntrl *mhi_cntrl, u64 pci_addr,
{
struct pci_epf_mhi *epf_mhi = to_epf_mhi(mhi_cntrl);
struct pci_epc *epc = epf_mhi->epf->epc;
- size_t offset = pci_addr & (epc->mem->window.page_size - 1);
+ size_t offset = get_align_offset(epc, pci_addr);

return __pci_epf_mhi_alloc_map(mhi_cntrl, pci_addr, paddr, vaddr,
offset, size);
@@ -161,7 +166,7 @@ static void pci_epf_mhi_unmap_free(struct mhi_ep_cntrl *mhi_cntrl, u64 pci_addr,
struct pci_epf_mhi *epf_mhi = to_epf_mhi(mhi_cntrl);
struct pci_epf *epf = epf_mhi->epf;
struct pci_epc *epc = epf->epc;
- size_t offset = pci_addr & (epc->mem->window.page_size - 1);
+ size_t offset = get_align_offset(epc, pci_addr);

__pci_epf_mhi_unmap_free(mhi_cntrl, pci_addr, paddr, vaddr, offset,
size);
@@ -185,7 +190,8 @@ static int pci_epf_mhi_read_from_host(struct mhi_ep_cntrl *mhi_cntrl, u64 from,
void *to, size_t size)
{
struct pci_epf_mhi *epf_mhi = to_epf_mhi(mhi_cntrl);
- size_t offset = from % SZ_4K;
+ struct pci_epc *epc = epf_mhi->epf->epc;
+ size_t offset = get_align_offset(epc, from);
void __iomem *tre_buf;
phys_addr_t tre_phys;
int ret;
@@ -213,7 +219,8 @@ static int pci_epf_mhi_write_to_host(struct mhi_ep_cntrl *mhi_cntrl,
void *from, u64 to, size_t size)
{
struct pci_epf_mhi *epf_mhi = to_epf_mhi(mhi_cntrl);
- size_t offset = to % SZ_4K;
+ struct pci_epc *epc = epf_mhi->epf->epc;
+ size_t offset = get_align_offset(epc, to);
void __iomem *tre_buf;
phys_addr_t tre_phys;
int ret;
--
2.25.1