On Tue, Jul 16, 2019 at 02:13:46PM +0200, Grzegorz Jaszczyk wrote:
> Perform conversion to little-endian before every write to configuration
> space and converse back to cpu endianness during read. Additionally
> initialise every not-byte wide fields of config space with proper
> cpu_to_le* macro.
>
> This is required since the structure describing config space of emulated
> bridge assumes little-endian convention.
>
> Signed-off-by: Grzegorz Jaszczyk <jaz@xxxxxxxxxxxx>
> ---
> v1->v2
> - use __le32 and __le16 for config fields
> - add missing cpu_to_le16 for pcie_conf.cap assignment
> - use __le32 for cfgspace pointer
> Issues with endianness were detected by Sparse tool recommended by Russell King.
>
> drivers/pci/pci-bridge-emul.c | 25 +++++++-------
> drivers/pci/pci-bridge-emul.h | 78 +++++++++++++++++++++----------------------
> 2 files changed, 52 insertions(+), 51 deletions(-)
Applied to pci/aardvark, thanks.
Lorenzo
> diff --git a/drivers/pci/pci-bridge-emul.c b/drivers/pci/pci-bridge-emul.c
> index 83fb077..cfae566 100644
> --- a/drivers/pci/pci-bridge-emul.c
> +++ b/drivers/pci/pci-bridge-emul.c
> @@ -270,10 +270,10 @@ const static struct pci_bridge_reg_behavior pcie_cap_regs_behavior[] = {
> int pci_bridge_emul_init(struct pci_bridge_emul *bridge,
> unsigned int flags)
> {
> - bridge->conf.class_revision |= PCI_CLASS_BRIDGE_PCI << 16;
> + bridge->conf.class_revision |= cpu_to_le32(PCI_CLASS_BRIDGE_PCI << 16);
> bridge->conf.header_type = PCI_HEADER_TYPE_BRIDGE;
> bridge->conf.cache_line_size = 0x10;
> - bridge->conf.status = PCI_STATUS_CAP_LIST;
> + bridge->conf.status = cpu_to_le16(PCI_STATUS_CAP_LIST);
> bridge->pci_regs_behavior = kmemdup(pci_regs_behavior,
> sizeof(pci_regs_behavior),
> GFP_KERNEL);
> @@ -284,8 +284,9 @@ int pci_bridge_emul_init(struct pci_bridge_emul *bridge,
> bridge->conf.capabilities_pointer = PCI_CAP_PCIE_START;
> bridge->pcie_conf.cap_id = PCI_CAP_ID_EXP;
> /* Set PCIe v2, root port, slot support */
> - bridge->pcie_conf.cap = PCI_EXP_TYPE_ROOT_PORT << 4 | 2 |
> - PCI_EXP_FLAGS_SLOT;
> + bridge->pcie_conf.cap =
> + cpu_to_le16(PCI_EXP_TYPE_ROOT_PORT << 4 | 2 |
> + PCI_EXP_FLAGS_SLOT);
> bridge->pcie_cap_regs_behavior =
> kmemdup(pcie_cap_regs_behavior,
> sizeof(pcie_cap_regs_behavior),
> @@ -327,7 +328,7 @@ int pci_bridge_emul_conf_read(struct pci_bridge_emul *bridge, int where,
> int reg = where & ~3;
> pci_bridge_emul_read_status_t (*read_op)(struct pci_bridge_emul *bridge,
> int reg, u32 *value);
> - u32 *cfgspace;
> + __le32 *cfgspace;
> const struct pci_bridge_reg_behavior *behavior;
>
> if (bridge->has_pcie && reg >= PCI_CAP_PCIE_END) {
> @@ -343,11 +344,11 @@ int pci_bridge_emul_conf_read(struct pci_bridge_emul *bridge, int where,
> if (bridge->has_pcie && reg >= PCI_CAP_PCIE_START) {
> reg -= PCI_CAP_PCIE_START;
> read_op = bridge->ops->read_pcie;
> - cfgspace = (u32 *) &bridge->pcie_conf;
> + cfgspace = (__le32 *) &bridge->pcie_conf;
> behavior = bridge->pcie_cap_regs_behavior;
> } else {
> read_op = bridge->ops->read_base;
> - cfgspace = (u32 *) &bridge->conf;
> + cfgspace = (__le32 *) &bridge->conf;
> behavior = bridge->pci_regs_behavior;
> }
>
> @@ -357,7 +358,7 @@ int pci_bridge_emul_conf_read(struct pci_bridge_emul *bridge, int where,
> ret = PCI_BRIDGE_EMUL_NOT_HANDLED;
>
> if (ret == PCI_BRIDGE_EMUL_NOT_HANDLED)
> - *value = cfgspace[reg / 4];
> + *value = le32_to_cpu(cfgspace[reg / 4]);
>
> /*
> * Make sure we never return any reserved bit with a value
> @@ -387,7 +388,7 @@ int pci_bridge_emul_conf_write(struct pci_bridge_emul *bridge, int where,
> int mask, ret, old, new, shift;
> void (*write_op)(struct pci_bridge_emul *bridge, int reg,
> u32 old, u32 new, u32 mask);
> - u32 *cfgspace;
> + __le32 *cfgspace;
> const struct pci_bridge_reg_behavior *behavior;
>
> if (bridge->has_pcie && reg >= PCI_CAP_PCIE_END)
> @@ -414,11 +415,11 @@ int pci_bridge_emul_conf_write(struct pci_bridge_emul *bridge, int where,
> if (bridge->has_pcie && reg >= PCI_CAP_PCIE_START) {
> reg -= PCI_CAP_PCIE_START;
> write_op = bridge->ops->write_pcie;
> - cfgspace = (u32 *) &bridge->pcie_conf;
> + cfgspace = (__le32 *) &bridge->pcie_conf;
> behavior = bridge->pcie_cap_regs_behavior;
> } else {
> write_op = bridge->ops->write_base;
> - cfgspace = (u32 *) &bridge->conf;
> + cfgspace = (__le32 *) &bridge->conf;
> behavior = bridge->pci_regs_behavior;
> }
>
> @@ -431,7 +432,7 @@ int pci_bridge_emul_conf_write(struct pci_bridge_emul *bridge, int where,
> /* Clear the W1C bits */
> new &= ~((value << shift) & (behavior[reg / 4].w1c & mask));
>
> - cfgspace[reg / 4] = new;
> + cfgspace[reg / 4] = cpu_to_le32(new);
>
> if (write_op)
> write_op(bridge, reg, old, new, mask);
> diff --git a/drivers/pci/pci-bridge-emul.h b/drivers/pci/pci-bridge-emul.h
> index e65b1b7..b318830 100644
> --- a/drivers/pci/pci-bridge-emul.h
> +++ b/drivers/pci/pci-bridge-emul.h
> @@ -6,65 +6,65 @@
>
> /* PCI configuration space of a PCI-to-PCI bridge. */
> struct pci_bridge_emul_conf {
> - u16 vendor;
> - u16 device;
> - u16 command;
> - u16 status;
> - u32 class_revision;
> + __le16 vendor;
> + __le16 device;
> + __le16 command;
> + __le16 status;
> + __le32 class_revision;
> u8 cache_line_size;
> u8 latency_timer;
> u8 header_type;
> u8 bist;
> - u32 bar[2];
> + __le32 bar[2];
> u8 primary_bus;
> u8 secondary_bus;
> u8 subordinate_bus;
> u8 secondary_latency_timer;
> u8 iobase;
> u8 iolimit;
> - u16 secondary_status;
> - u16 membase;
> - u16 memlimit;
> - u16 pref_mem_base;
> - u16 pref_mem_limit;
> - u32 prefbaseupper;
> - u32 preflimitupper;
> - u16 iobaseupper;
> - u16 iolimitupper;
> + __le16 secondary_status;
> + __le16 membase;
> + __le16 memlimit;
> + __le16 pref_mem_base;
> + __le16 pref_mem_limit;
> + __le32 prefbaseupper;
> + __le32 preflimitupper;
> + __le16 iobaseupper;
> + __le16 iolimitupper;
> u8 capabilities_pointer;
> u8 reserve[3];
> - u32 romaddr;
> + __le32 romaddr;
> u8 intline;
> u8 intpin;
> - u16 bridgectrl;
> + __le16 bridgectrl;
> };
>
> /* PCI configuration space of the PCIe capabilities */
> struct pci_bridge_emul_pcie_conf {
> u8 cap_id;
> u8 next;
> - u16 cap;
> - u32 devcap;
> - u16 devctl;
> - u16 devsta;
> - u32 lnkcap;
> - u16 lnkctl;
> - u16 lnksta;
> - u32 slotcap;
> - u16 slotctl;
> - u16 slotsta;
> - u16 rootctl;
> - u16 rsvd;
> - u32 rootsta;
> - u32 devcap2;
> - u16 devctl2;
> - u16 devsta2;
> - u32 lnkcap2;
> - u16 lnkctl2;
> - u16 lnksta2;
> - u32 slotcap2;
> - u16 slotctl2;
> - u16 slotsta2;
> + __le16 cap;
> + __le32 devcap;
> + __le16 devctl;
> + __le16 devsta;
> + __le32 lnkcap;
> + __le16 lnkctl;
> + __le16 lnksta;
> + __le32 slotcap;
> + __le16 slotctl;
> + __le16 slotsta;
> + __le16 rootctl;
> + __le16 rsvd;
> + __le32 rootsta;
> + __le32 devcap2;
> + __le16 devctl2;
> + __le16 devsta2;
> + __le32 lnkcap2;
> + __le16 lnkctl2;
> + __le16 lnksta2;
> + __le32 slotcap2;
> + __le16 slotctl2;
> + __le16 slotsta2;
> };
>
> struct pci_bridge_emul;
> --
> 2.7.4
>
