[Top] [All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [patch V2 01/23] powerpc/4xx: Remove MSI support which never worked

On 12/7/21 12:36, Michael Ellerman wrote:

Cédric Le Goater <clg@xxxxxxxx> writes:

Hello Thomas,

On 12/6/21 23:27, Thomas Gleixner wrote:

This code is broken since day one. ppc4xx_setup_msi_irqs() has the
following gems:

   1) The handling of the result of msi_bitmap_alloc_hwirqs() is completely
      broken:
When the result is greater than or equal 0 (bitmap allocation 
      successful) then the loop terminates and the function returns 0
      (success) despite not having installed an interrupt.

      When the result is less than 0 (bitmap allocation fails), it prints an
      error message and continues to "work" with that error code which would
      eventually end up in the MSI message data.

   2) On every invocation the file global pp4xx_msi::msi_virqs bitmap is
      allocated thereby leaking the previous one.

IOW, this has never worked and for more than 10 years nobody cared. Remove
the gunk.

Fixes: 3fb7933850fa ("powerpc/4xx: Adding PCIe MSI support")


Shouldn't we remove all of it ? including the updates in the device trees
and the Kconfig changes under :

arch/powerpc/platforms/44x/Kconfig:     select PPC4xx_MSI
arch/powerpc/platforms/44x/Kconfig:     select PPC4xx_MSI
arch/powerpc/platforms/44x/Kconfig:     select PPC4xx_MSI
arch/powerpc/platforms/44x/Kconfig:     select PPC4xx_MSI
arch/powerpc/platforms/40x/Kconfig:     select PPC4xx_MSI


This patch should drop those selects I guess. Can you send an
incremental diff for Thomas to squash in?


Sure.


Removing all the tendrils in various device tree files will probably
require some archaeology, and it should be perfectly safe to leave those
in the tree with the driver gone. So I think we can do that as a
subsequent patch, rather than in this series.


Here are the changes. Compiled tested with ppc40x and ppc44x defconfigs.

Thanks,

C.

diff --git a/arch/powerpc/boot/dts/bluestone.dts 
b/arch/powerpc/boot/dts/bluestone.dts
index aa1ae94cd776..6971595319c1 100644
--- a/arch/powerpc/boot/dts/bluestone.dts
+++ b/arch/powerpc/boot/dts/bluestone.dts
@@ -366,30 +366,5 @@ PCIE0: pcie@d00000000 {
                                0x0 0x0 0x0 0x3 &UIC3 0xe 0x4 /* swizzled int C 
*/
                                0x0 0x0 0x0 0x4 &UIC3 0xf 0x4 /* swizzled int D 
*/>;
                };
-
-               MSI: ppc4xx-msi@C10000000 {
-                       compatible = "amcc,ppc4xx-msi", "ppc4xx-msi";
-                       reg = < 0xC 0x10000000 0x100
-                               0xC 0x10000000 0x100>;
-                       sdr-base = <0x36C>;
-                       msi-data = <0x00004440>;
-                       msi-mask = <0x0000ffe0>;
-                       interrupts =<0 1 2 3 4 5 6 7>;
-                       interrupt-parent = <&MSI>;
-                       #interrupt-cells = <1>;
-                       #address-cells = <0>;
-                       #size-cells = <0>;
-                       msi-available-ranges = <0x0 0x100>;
-                       interrupt-map = <
-                               0 &UIC3 0x18 1
-                               1 &UIC3 0x19 1
-                               2 &UIC3 0x1A 1
-                               3 &UIC3 0x1B 1
-                               4 &UIC3 0x1C 1
-                               5 &UIC3 0x1D 1
-                               6 &UIC3 0x1E 1
-                               7 &UIC3 0x1F 1
-                       >;
-               };
        };
 };
diff --git a/arch/powerpc/boot/dts/canyonlands.dts 
b/arch/powerpc/boot/dts/canyonlands.dts
index c5fbb08e0a6e..5db1bff6b23d 100644
--- a/arch/powerpc/boot/dts/canyonlands.dts
+++ b/arch/powerpc/boot/dts/canyonlands.dts
@@ -544,23 +544,5 @@ PCIE1: pcie@d20000000 {
                                0x0 0x0 0x0 0x3 &UIC3 0x12 0x4 /* swizzled int 
C */
                                0x0 0x0 0x0 0x4 &UIC3 0x13 0x4 /* swizzled int D 
*/>;
                };
-
-               MSI: ppc4xx-msi@C10000000 {
-                       compatible = "amcc,ppc4xx-msi", "ppc4xx-msi";
-                       reg = < 0xC 0x10000000 0x100>;
-                       sdr-base = <0x36C>;
-                       msi-data = <0x00000000>;
-                       msi-mask = <0x44440000>;
-                       interrupt-count = <3>;
-                       interrupts = <0 1 2 3>;
-                       interrupt-parent = <&UIC3>;
-                       #interrupt-cells = <1>;
-                       #address-cells = <0>;
-                       #size-cells = <0>;
-                       interrupt-map = <0 &UIC3 0x18 1
-                                       1 &UIC3 0x19 1
-                                       2 &UIC3 0x1A 1
-                                       3 &UIC3 0x1B 1>;
-               };
        };
 };
diff --git a/arch/powerpc/boot/dts/katmai.dts b/arch/powerpc/boot/dts/katmai.dts
index a8f353229fb7..4262b2bbd6de 100644
--- a/arch/powerpc/boot/dts/katmai.dts
+++ b/arch/powerpc/boot/dts/katmai.dts
@@ -442,24 +442,6 @@ PCIE2: pcie@d40000000 {
                                0x0 0x0 0x0 0x4 &UIC3 0xb 0x4 /* swizzled int D 
*/>;
                };
- MSI: ppc4xx-msi@400300000 { 
-                               compatible = "amcc,ppc4xx-msi", "ppc4xx-msi";
-                               reg = < 0x4 0x00300000 0x100>;
-                               sdr-base = <0x3B0>;
-                               msi-data = <0x00000000>;
-                               msi-mask = <0x44440000>;
-                               interrupt-count = <3>;
-                               interrupts =<0 1 2 3>;
-                               interrupt-parent = <&UIC0>;
-                               #interrupt-cells = <1>;
-                               #address-cells = <0>;
-                               #size-cells = <0>;
-                               interrupt-map = <0 &UIC0 0xC 1
-                                       1 &UIC0 0x0D 1
-                                       2 &UIC0 0x0E 1
-                                       3 &UIC0 0x0F 1>;
-               };
-
                I2O: i2o@400100000 {
                        compatible = "ibm,i2o-440spe";
                        reg = <0x00000004 0x00100000 0x100>;
diff --git a/arch/powerpc/boot/dts/kilauea.dts 
b/arch/powerpc/boot/dts/kilauea.dts
index a709fb47a180..c07a7525a72c 100644
--- a/arch/powerpc/boot/dts/kilauea.dts
+++ b/arch/powerpc/boot/dts/kilauea.dts
@@ -403,33 +403,5 @@ PCIE1: pcie@c0000000 {
                                0x0 0x0 0x0 0x3 &UIC2 0xd 0x4 /* swizzled int C 
*/
                                0x0 0x0 0x0 0x4 &UIC2 0xe 0x4 /* swizzled int D 
*/>;
                };
-
-               MSI: ppc4xx-msi@C10000000 {
-                       compatible = "amcc,ppc4xx-msi", "ppc4xx-msi";
-                       reg = <0xEF620000 0x100>;
-                       sdr-base = <0x4B0>;
-                       msi-data = <0x00000000>;
-                       msi-mask = <0x44440000>;
-                       interrupt-count = <12>;
-                       interrupts = <0 1 2 3 4 5 6 7 8 9 0xA 0xB 0xC 0xD>;
-                       interrupt-parent = <&UIC2>;
-                       #interrupt-cells = <1>;
-                       #address-cells = <0>;
-                       #size-cells = <0>;
-                       interrupt-map = <0 &UIC2 0x10 1
-                                       1 &UIC2 0x11 1
-                                       2 &UIC2 0x12 1
-                                       2 &UIC2 0x13 1
-                                       2 &UIC2 0x14 1
-                                       2 &UIC2 0x15 1
-                                       2 &UIC2 0x16 1
-                                       2 &UIC2 0x17 1
-                                       2 &UIC2 0x18 1
-                                       2 &UIC2 0x19 1
-                                       2 &UIC2 0x1A 1
-                                       2 &UIC2 0x1B 1
-                                       2 &UIC2 0x1C 1
-                                       3 &UIC2 0x1D 1>;
-               };
        };
 };
diff --git a/arch/powerpc/boot/dts/redwood.dts 
b/arch/powerpc/boot/dts/redwood.dts
index f38035a1f4a1..3c849e23e5f3 100644
--- a/arch/powerpc/boot/dts/redwood.dts
+++ b/arch/powerpc/boot/dts/redwood.dts
@@ -358,25 +358,6 @@ PCIE2: pcie@d40000000 {
                                0x0 0x0 0x0 0x4 &UIC3 0xb 0x4 /* swizzled int D 
*/>;
                };
- MSI: ppc4xx-msi@400300000 { 
-                               compatible = "amcc,ppc4xx-msi", "ppc4xx-msi";
-                               reg = < 0x4 0x00300000 0x100
-                                       0x4 0x00300000 0x100>;
-                               sdr-base = <0x3B0>;
-                               msi-data = <0x00000000>;
-                               msi-mask = <0x44440000>;
-                               interrupt-count = <3>;
-                               interrupts =<0 1 2 3>;
-                               interrupt-parent = <&UIC0>;
-                               #interrupt-cells = <1>;
-                               #address-cells = <0>;
-                               #size-cells = <0>;
-                               interrupt-map = <0 &UIC0 0xC 1
-                                       1 &UIC0 0x0D 1
-                                       2 &UIC0 0x0E 1
-                                       3 &UIC0 0x0F 1>;
-               };
-
        };
diff --git a/arch/powerpc/platforms/40x/Kconfig b/arch/powerpc/platforms/40x/Kconfig 
index e3e5217c9822..614ea6dc994c 100644
--- a/arch/powerpc/platforms/40x/Kconfig
+++ b/arch/powerpc/platforms/40x/Kconfig
@@ -23,7 +23,6 @@ config KILAUEA
        select PPC4xx_PCI_EXPRESS
        select FORCE_PCI
        select PCI_MSI
-       select PPC4xx_MSI
        help
          This option enables support for the AMCC PPC405EX evaluation board.
diff --git a/arch/powerpc/platforms/44x/Kconfig b/arch/powerpc/platforms/44x/Kconfig 
index 83975ef50975..25b80cd558f8 100644
--- a/arch/powerpc/platforms/44x/Kconfig
+++ b/arch/powerpc/platforms/44x/Kconfig
@@ -23,7 +23,6 @@ config BLUESTONE
        select APM821xx
        select FORCE_PCI
        select PCI_MSI
-       select PPC4xx_MSI
        select PPC4xx_PCI_EXPRESS
        select IBM_EMAC_RGMII if IBM_EMAC
        help
@@ -73,7 +72,6 @@ config KATMAI
        select FORCE_PCI
        select PPC4xx_PCI_EXPRESS
        select PCI_MSI
-       select PPC4xx_MSI
        help
          This option enables support for the AMCC PPC440SPe evaluation board.
@@ -115,7 +113,6 @@ config CANYONLANDS 
        select FORCE_PCI
        select PPC4xx_PCI_EXPRESS
        select PCI_MSI
-       select PPC4xx_MSI
        select IBM_EMAC_RGMII if IBM_EMAC
        select IBM_EMAC_ZMII if IBM_EMAC
        help
@@ -141,7 +138,6 @@ config REDWOOD
        select FORCE_PCI
        select PPC4xx_PCI_EXPRESS
        select PCI_MSI
-       select PPC4xx_MSI
        help
          This option enables support for the AMCC PPC460SX Redwood board.
-- 
2.31.1

 

©2013 Xen Project, A Linux Foundation Collaborative Project. All Rights Reserved.
Linux Foundation is a registered trademark of The Linux Foundation.
Xen Project is a trademark of The Linux Foundation.

Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.