From c1b8d45db4dbc64cc6015f97922f767fdf782f64 Mon Sep 17 00:00:00 2001 From: Kyle Moffett Date: Thu, 22 Dec 2011 10:19:13 +0000 Subject: [PATCH] powerpc/mpic: Add "last-interrupt-source" property to override hardware The FreeScale PowerQUICC-III-compatible (mpc85xx/mpc86xx) MPICs do not correctly report the number of hardware interrupt sources, so software needs to override the detected value with "256". To avoid needing to write custom board-specific code to detect that scenario, allow it to be easily overridden in the device-tree. Signed-off-by: Kyle Moffett Signed-off-by: Benjamin Herrenschmidt --- .../devicetree/bindings/powerpc/fsl/mpic.txt | 7 +++ arch/powerpc/boot/dts/fsl/pq3-mpic.dtsi | 1 + arch/powerpc/sysdev/mpic.c | 46 +++++++++++-------- 3 files changed, 34 insertions(+), 20 deletions(-) diff --git a/Documentation/devicetree/bindings/powerpc/fsl/mpic.txt b/Documentation/devicetree/bindings/powerpc/fsl/mpic.txt index b393ccf1e9f3..dc5744636a57 100644 --- a/Documentation/devicetree/bindings/powerpc/fsl/mpic.txt +++ b/Documentation/devicetree/bindings/powerpc/fsl/mpic.txt @@ -70,6 +70,13 @@ PROPERTIES If present the MPIC will be assumed to only be able to route non-IPI interrupts to a single CPU at a time (EG: Freescale MPIC). + - last-interrupt-source + Usage: optional + Value type: + Some MPICs do not correctly report the number of hardware sources + in the global feature registers. If specified, this field will + override the value read from MPIC_GREG_FEATURE_LAST_SRC. + INTERRUPT SPECIFIER DEFINITION Interrupt specifiers consists of 4 cells encoded as diff --git a/arch/powerpc/boot/dts/fsl/pq3-mpic.dtsi b/arch/powerpc/boot/dts/fsl/pq3-mpic.dtsi index 658bd81982cb..fdedf7b1fe0f 100644 --- a/arch/powerpc/boot/dts/fsl/pq3-mpic.dtsi +++ b/arch/powerpc/boot/dts/fsl/pq3-mpic.dtsi @@ -41,6 +41,7 @@ mpic: pic@40000 { device_type = "open-pic"; big-endian; single-cpu-affinity; + last-interrupt-source = <255>; }; timer@41100 { diff --git a/arch/powerpc/sysdev/mpic.c b/arch/powerpc/sysdev/mpic.c index cbffeb742d66..90171d447c3d 100644 --- a/arch/powerpc/sysdev/mpic.c +++ b/arch/powerpc/sysdev/mpic.c @@ -1149,6 +1149,7 @@ struct mpic * __init mpic_alloc(struct device_node *node, u32 greg_feature; const char *vers; const u32 *psrc; + u32 last_irq; /* Default MPIC search parameters */ static const struct of_device_id __initconst mpic_device_id[] = { @@ -1220,7 +1221,6 @@ struct mpic * __init mpic_alloc(struct device_node *node, mpic->hc_tm = mpic_tm_chip; mpic->hc_tm.name = name; - mpic->isu_size = isu_size; mpic->num_sources = 0; /* so far */ if (mpic->flags & MPIC_LARGE_VECTORS) @@ -1307,20 +1307,6 @@ struct mpic * __init mpic_alloc(struct device_node *node, mpic_read(mpic->gregs, MPIC_INFO(GREG_GLOBAL_CONF_0)) | MPIC_GREG_GCONF_MCK); - /* - * Read feature register. For non-ISU MPICs, num sources as well. On - * ISU MPICs, sources are counted as ISUs are added - */ - greg_feature = mpic_read(mpic->gregs, MPIC_INFO(GREG_FEATURE_0)); - if (isu_size == 0) { - if (irq_count) - mpic->num_sources = irq_count; - else - mpic->num_sources = - ((greg_feature & MPIC_GREG_FEATURE_LAST_SRC_MASK) - >> MPIC_GREG_FEATURE_LAST_SRC_SHIFT) + 1; - } - /* * The MPIC driver will crash if there are more cores than we * can initialize, so we may as well catch that problem here. @@ -1336,18 +1322,38 @@ struct mpic * __init mpic_alloc(struct device_node *node, 0x1000); } + /* + * Read feature register. For non-ISU MPICs, num sources as well. On + * ISU MPICs, sources are counted as ISUs are added + */ + greg_feature = mpic_read(mpic->gregs, MPIC_INFO(GREG_FEATURE_0)); + + /* + * By default, the last source number comes from the MPIC, but the + * device-tree and board support code can override it on buggy hw. + */ + last_irq = (greg_feature & MPIC_GREG_FEATURE_LAST_SRC_MASK) + >> MPIC_GREG_FEATURE_LAST_SRC_SHIFT; + of_property_read_u32(mpic->node, "last-interrupt-source", &last_irq); + if (irq_count) + last_irq = irq_count - 1; + /* Initialize main ISU if none provided */ - if (mpic->isu_size == 0) { - mpic->isu_size = mpic->num_sources; + if (!isu_size) { + isu_size = last_irq + 1; + mpic->num_sources = isu_size; mpic_map(mpic, mpic->paddr, &mpic->isus[0], - MPIC_INFO(IRQ_BASE), MPIC_INFO(IRQ_STRIDE) * mpic->isu_size); + MPIC_INFO(IRQ_BASE), + MPIC_INFO(IRQ_STRIDE) * isu_size); } + + mpic->isu_size = isu_size; mpic->isu_shift = 1 + __ilog2(mpic->isu_size - 1); mpic->isu_mask = (1 << mpic->isu_shift) - 1; mpic->irqhost = irq_alloc_host(mpic->node, IRQ_HOST_MAP_LINEAR, - isu_size ? isu_size : mpic->num_sources, - &mpic_host_ops, intvec_top + 1); + mpic->isu_size, &mpic_host_ops, + intvec_top + 1); /* * FIXME: The code leaks the MPIC object and mappings here; this -- 2.20.1