2019-08-09 10:36:16

by Thomas Bogendoerfer

Subject: [PATCH v4 4/9] MIPS: PCI: refactor ioc3 special handling

Refactored code to only have one ioc3 special handling for read
access and one for write access.

Signed-off-by: Thomas Bogendoerfer <[email protected]>
---
arch/mips/pci/pci-xtalk-bridge.c | 167 +++++++++++++++------------------------
1 file changed, 62 insertions(+), 105 deletions(-)

diff --git a/arch/mips/pci/pci-xtalk-bridge.c b/arch/mips/pci/pci-xtalk-bridge.c
index bcf7f559789a..7b4d40354ee7 100644
--- a/arch/mips/pci/pci-xtalk-bridge.c
+++ b/arch/mips/pci/pci-xtalk-bridge.c
@@ -20,16 +20,50 @@
* Most of the IOC3 PCI config register aren't present
* we emulate what is needed for a normal PCI enumeration
*/
-static u32 emulate_ioc3_cfg(int where, int size)
+static int ioc3_cfg_rd(void *addr, int where, int size, u32 *value)
{
- if (size == 1 && where == 0x3d)
- return 0x01;
- else if (size == 2 && where == 0x3c)
- return 0x0100;
- else if (size == 4 && where == 0x3c)
- return 0x00000100;
+ u32 cf, shift, mask;

- return 0;
+ switch (where & ~3) {
+ case 0x00 ... 0x10:
+ case 0x40 ... 0x44:
+ if (get_dbe(cf, (u32 *)addr))
+ return PCIBIOS_DEVICE_NOT_FOUND;
+ break;
+ case 0x3c:
+ /* emulate sane interrupt pin value */
+ cf = 0x00000100;
+ break;
+ default:
+ cf = 0;
+ break;
+ }
+ shift = (where & 3) << 3;
+ mask = 0xffffffffU >> ((4 - size) << 3);
+ *value = (cf >> shift) & mask;
+
+ return PCIBIOS_SUCCESSFUL;
+}
+
+static int ioc3_cfg_wr(void *addr, int where, int size, u32 value)
+{
+ u32 cf, shift, mask, smask;
+
+ if ((where >= 0x14 && where < 0x40) || (where >= 0x48))
+ return PCIBIOS_SUCCESSFUL;
+
+ if (get_dbe(cf, (u32 *)addr))
+ return PCIBIOS_DEVICE_NOT_FOUND;
+
+ shift = ((where & 3) << 3);
+ mask = (0xffffffffU >> ((4 - size) << 3));
+ smask = mask << shift;
+
+ cf = (cf & ~smask) | ((value & mask) << shift);
+ if (put_dbe(cf, (u32 *)addr))
+ return PCIBIOS_DEVICE_NOT_FOUND;
+
+ return PCIBIOS_SUCCESSFUL;
}

static void bridge_disable_swapping(struct pci_dev *dev)
@@ -64,7 +98,7 @@ static int pci_conf0_read_config(struct pci_bus *bus, unsigned int devfn,
int slot = PCI_SLOT(devfn);
int fn = PCI_FUNC(devfn);
void *addr;
- u32 cf, shift, mask;
+ u32 cf;
int res;

addr = &bridge->b_type0_cfg_dev[slot].f[fn].c[PCI_VENDOR_ID];
@@ -75,8 +109,10 @@ static int pci_conf0_read_config(struct pci_bus *bus, unsigned int devfn,
* IOC3 is broken beyond belief ... Don't even give the
* generic PCI code a chance to look at it for real ...
*/
- if (cf == (PCI_VENDOR_ID_SGI | (PCI_DEVICE_ID_SGI_IOC3 << 16)))
- goto is_ioc3;
+ if (cf == (PCI_VENDOR_ID_SGI | (PCI_DEVICE_ID_SGI_IOC3 << 16))) {
+ addr = &bridge->b_type0_cfg_dev[slot].f[fn].l[where >> 2];
+ return ioc3_cfg_rd(addr, where, size, value);
+ }

addr = &bridge->b_type0_cfg_dev[slot].f[fn].c[where ^ (4 - size)];

@@ -88,26 +124,6 @@ static int pci_conf0_read_config(struct pci_bus *bus, unsigned int devfn,
res = get_dbe(*value, (u32 *)addr);

return res ? PCIBIOS_DEVICE_NOT_FOUND : PCIBIOS_SUCCESSFUL;
-
-is_ioc3:
-
- /*
- * IOC3 special handling
- */
- if ((where >= 0x14 && where < 0x40) || (where >= 0x48)) {
- *value = emulate_ioc3_cfg(where, size);
- return PCIBIOS_SUCCESSFUL;
- }
-
- addr = &bridge->b_type0_cfg_dev[slot].f[fn].l[where >> 2];
- if (get_dbe(cf, (u32 *)addr))
- return PCIBIOS_DEVICE_NOT_FOUND;
-
- shift = ((where & 3) << 3);
- mask = (0xffffffffU >> ((4 - size) << 3));
- *value = (cf >> shift) & mask;
-
- return PCIBIOS_SUCCESSFUL;
}

static int pci_conf1_read_config(struct pci_bus *bus, unsigned int devfn,
@@ -119,7 +135,7 @@ static int pci_conf1_read_config(struct pci_bus *bus, unsigned int devfn,
int slot = PCI_SLOT(devfn);
int fn = PCI_FUNC(devfn);
void *addr;
- u32 cf, shift, mask;
+ u32 cf;
int res;

bridge_write(bc, b_pci_cfg, (busno << 16) | (slot << 11));
@@ -131,8 +147,10 @@ static int pci_conf1_read_config(struct pci_bus *bus, unsigned int devfn,
* IOC3 is broken beyond belief ... Don't even give the
* generic PCI code a chance to look at it for real ...
*/
- if (cf == (PCI_VENDOR_ID_SGI | (PCI_DEVICE_ID_SGI_IOC3 << 16)))
- goto is_ioc3;
+ if (cf == (PCI_VENDOR_ID_SGI | (PCI_DEVICE_ID_SGI_IOC3 << 16))) {
+ addr = &bridge->b_type1_cfg.c[(fn << 8) | (where & ~3)];
+ return ioc3_cfg_rd(addr, where, size, value);
+ }

addr = &bridge->b_type1_cfg.c[(fn << 8) | (where ^ (4 - size))];

@@ -144,26 +162,6 @@ static int pci_conf1_read_config(struct pci_bus *bus, unsigned int devfn,
res = get_dbe(*value, (u32 *)addr);

return res ? PCIBIOS_DEVICE_NOT_FOUND : PCIBIOS_SUCCESSFUL;
-
-is_ioc3:
-
- /*
- * IOC3 special handling
- */
- if ((where >= 0x14 && where < 0x40) || (where >= 0x48)) {
- *value = emulate_ioc3_cfg(where, size);
- return PCIBIOS_SUCCESSFUL;
- }
-
- addr = &bridge->b_type1_cfg.c[(fn << 8) | where];
- if (get_dbe(cf, (u32 *)addr))
- return PCIBIOS_DEVICE_NOT_FOUND;
-
- shift = ((where & 3) << 3);
- mask = (0xffffffffU >> ((4 - size) << 3));
- *value = (cf >> shift) & mask;
-
- return PCIBIOS_SUCCESSFUL;
}

static int pci_read_config(struct pci_bus *bus, unsigned int devfn,
@@ -183,7 +181,7 @@ static int pci_conf0_write_config(struct pci_bus *bus, unsigned int devfn,
int slot = PCI_SLOT(devfn);
int fn = PCI_FUNC(devfn);
void *addr;
- u32 cf, shift, mask, smask;
+ u32 cf;
int res;

addr = &bridge->b_type0_cfg_dev[slot].f[fn].c[PCI_VENDOR_ID];
@@ -194,8 +192,10 @@ static int pci_conf0_write_config(struct pci_bus *bus, unsigned int devfn,
* IOC3 is broken beyond belief ... Don't even give the
* generic PCI code a chance to look at it for real ...
*/
- if (cf == (PCI_VENDOR_ID_SGI | (PCI_DEVICE_ID_SGI_IOC3 << 16)))
- goto is_ioc3;
+ if (cf == (PCI_VENDOR_ID_SGI | (PCI_DEVICE_ID_SGI_IOC3 << 16))) {
+ addr = &bridge->b_type0_cfg_dev[slot].f[fn].l[where >> 2];
+ return ioc3_cfg_wr(addr, where, size, value);
+ }

addr = &bridge->b_type0_cfg_dev[slot].f[fn].c[where ^ (4 - size)];

@@ -210,29 +210,6 @@ static int pci_conf0_write_config(struct pci_bus *bus, unsigned int devfn,
return PCIBIOS_DEVICE_NOT_FOUND;

return PCIBIOS_SUCCESSFUL;
-
-is_ioc3:
-
- /*
- * IOC3 special handling
- */
- if ((where >= 0x14 && where < 0x40) || (where >= 0x48))
- return PCIBIOS_SUCCESSFUL;
-
- addr = &bridge->b_type0_cfg_dev[slot].f[fn].l[where >> 2];
-
- if (get_dbe(cf, (u32 *)addr))
- return PCIBIOS_DEVICE_NOT_FOUND;
-
- shift = ((where & 3) << 3);
- mask = (0xffffffffU >> ((4 - size) << 3));
- smask = mask << shift;
-
- cf = (cf & ~smask) | ((value & mask) << shift);
- if (put_dbe(cf, (u32 *)addr))
- return PCIBIOS_DEVICE_NOT_FOUND;
-
- return PCIBIOS_SUCCESSFUL;
}

static int pci_conf1_write_config(struct pci_bus *bus, unsigned int devfn,
@@ -244,7 +221,7 @@ static int pci_conf1_write_config(struct pci_bus *bus, unsigned int devfn,
int fn = PCI_FUNC(devfn);
int busno = bus->number;
void *addr;
- u32 cf, shift, mask, smask;
+ u32 cf;
int res;

bridge_write(bc, b_pci_cfg, (busno << 16) | (slot << 11));
@@ -256,8 +233,10 @@ static int pci_conf1_write_config(struct pci_bus *bus, unsigned int devfn,
* IOC3 is broken beyond belief ... Don't even give the
* generic PCI code a chance to look at it for real ...
*/
- if (cf == (PCI_VENDOR_ID_SGI | (PCI_DEVICE_ID_SGI_IOC3 << 16)))
- goto is_ioc3;
+ if (cf == (PCI_VENDOR_ID_SGI | (PCI_DEVICE_ID_SGI_IOC3 << 16))) {
+ addr = &bridge->b_type0_cfg_dev[slot].f[fn].l[where >> 2];
+ return ioc3_cfg_wr(addr, where, size, value);
+ }

addr = &bridge->b_type1_cfg.c[(fn << 8) | (where ^ (4 - size))];

@@ -272,28 +251,6 @@ static int pci_conf1_write_config(struct pci_bus *bus, unsigned int devfn,
return PCIBIOS_DEVICE_NOT_FOUND;

return PCIBIOS_SUCCESSFUL;
-
-is_ioc3:
-
- /*
- * IOC3 special handling
- */
- if ((where >= 0x14 && where < 0x40) || (where >= 0x48))
- return PCIBIOS_SUCCESSFUL;
-
- addr = &bridge->b_type0_cfg_dev[slot].f[fn].l[where >> 2];
- if (get_dbe(cf, (u32 *)addr))
- return PCIBIOS_DEVICE_NOT_FOUND;
-
- shift = ((where & 3) << 3);
- mask = (0xffffffffU >> ((4 - size) << 3));
- smask = mask << shift;
-
- cf = (cf & ~smask) | ((value & mask) << shift);
- if (put_dbe(cf, (u32 *)addr))
- return PCIBIOS_DEVICE_NOT_FOUND;
-
- return PCIBIOS_SUCCESSFUL;
}

static int pci_write_config(struct pci_bus *bus, unsigned int devfn,
--
2.13.7

2019-08-29 11:39:49

by Thomas Bogendoerfer

Subject: Re: [PATCH v4 4/9] MIPS: PCI: refactor ioc3 special handling

On Fri, Aug 09, 2019 at 12:32:26PM +0200, Thomas Bogendoerfer wrote:
> Refactored code to only have one ioc3 special handling for read
> access and one for write access.
>
> Signed-off-by: Thomas Bogendoerfer <[email protected]>
> ---
> arch/mips/pci/pci-xtalk-bridge.c | 167 +++++++++++++++------------------------
> 1 file changed, 62 insertions(+), 105 deletions(-)
> [..]

Paul,

it looks like this won't make it into the next merge window, but
I want to reduce the number of patches in this series.

Could you take this patch into mips-next ?

Thomas.

--
Crap can work. Given enough thrust pigs will fly, but it's not necessarily a
good idea. [ RFC1925, 2.3 ]