[PATCH 2/2] PCI: spear13xx: Avoid invalid address space conversions

Bjorn Helgaas
2021-12-23T21:38:09Z

The sparse checker complains about converting pointers between address
spaces. We correctly stored an __iomem pointer in struct spear13xx_pcie,
but discarded the __iomem when extracting app_base, causing one warning.
Then we passed the non-__iomem pointer to writel(), which expects an
__iomem pointer, causing another warning.

Add the appropriate annotations.

The sparse warnings look like this:

$ make C=2 drivers/pci/controller/
drivers/pci/controller/dwc/pcie-spear13xx.c:72:54: warning: incorrect type in initializer (different address spaces)
drivers/pci/controller/dwc/pcie-spear13xx.c:72:54: expected struct pcie_app_reg *app_reg
drivers/pci/controller/dwc/pcie-spear13xx.c:72:54: got void [noderef] __iomem *app_base
drivers/pci/controller/dwc/pcie-spear13xx.c:78:26: warning: incorrect type in argument 2 (different address spaces)
drivers/pci/controller/dwc/pcie-spear13xx.c:78:26: expected void volatile [noderef] __iomem *addr
drivers/pci/controller/dwc/pcie-spear13xx.c:78:26: got unsigned int *

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Pratyush Anand <pratyush.anand@gmail.com>
---
drivers/pci/controller/dwc/pcie-spear13xx.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-spear13xx.c b/drivers/pci/controller/dwc/pcie-spear13xx.c
index 1a9e353bef55..1569e82b5568 100644
--- a/drivers/pci/controller/dwc/pcie-spear13xx.c
+++ b/drivers/pci/controller/dwc/pcie-spear13xx.c
@@ -69,7 +69,7 @@ struct pcie_app_reg {
static int spear13xx_pcie_start_link(struct dw_pcie *pci)
{
struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(pci);
- struct pcie_app_reg *app_reg = spear13xx_pcie->app_base;
+ struct pcie_app_reg __iomem *app_reg = spear13xx_pcie->app_base;

/* enable ltssm */
writel(DEVICE_TYPE_RC | (1 << MISCTRL_EN_ID)
@@ -83,7 +83,7 @@ static int spear13xx_pcie_start_link(struct dw_pcie *pci)
static irqreturn_t spear13xx_pcie_irq_handler(int irq, void *arg)
{
struct spear13xx_pcie *spear13xx_pcie = arg;
- struct pcie_app_reg *app_reg = spear13xx_pcie->app_base;
+ struct pcie_app_reg __iomem *app_reg = spear13xx_pcie->app_base;
struct dw_pcie *pci = spear13xx_pcie->pci;
struct pcie_port *pp = &pci->pp;
unsigned int status;
@@ -102,7 +102,7 @@ static irqreturn_t spear13xx_pcie_irq_handler(int irq, void *arg)

static void spear13xx_pcie_enable_interrupts(struct spear13xx_pcie *spear13xx_pcie)
{
- struct pcie_app_reg *app_reg = spear13xx_pcie->app_base;
+ struct pcie_app_reg __iomem *app_reg = spear13xx_pcie->app_base;

/* Enable MSI interrupt */
if (IS_ENABLED(CONFIG_PCI_MSI))
@@ -113,7 +113,7 @@ static void spear13xx_pcie_enable_interrupts(struct spear13xx_pcie *spear13xx_pc
static int spear13xx_pcie_link_up(struct dw_pcie *pci)
{
struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(pci);
- struct pcie_app_reg *app_reg = spear13xx_pcie->app_base;
+ struct pcie_app_reg __iomem *app_reg = spear13xx_pcie->app_base;

if (readl(&app_reg->app_status_1) & XMLH_LINK_UP)
return 1;
--
2.25.1