brcm2708: update to latest patches from RPi Foundation

[openwrt/openwrt.git] / target / linux / brcm2708 / patches-4.19 / 950-0031-irqchip-irq-bcm2836-Remove-regmap-and-syscon-use.patch

diff --git a/target/linux/brcm2708/patches-4.19/950-0031-irqchip-irq-bcm2836-Remove-regmap-and-syscon-use.patch b/target/linux/brcm2708/patches-4.19/950-0031-irqchip-irq-bcm2836-Remove-regmap-and-syscon-use.patch
new file mode 100644 (file)
index 0000000..0881053
--- /dev/null
+++ b/target/linux/brcm2708/patches-4.19/950-0031-irqchip-irq-bcm2836-Remove-regmap-and-syscon-use.patch
@@ -0,0 +1,112 @@
+From f1905bc5137db49ef155f835d52d68cb86c4c9a9 Mon Sep 17 00:00:00 2001
+From: Phil Elwell <phil@raspberrypi.org>
+Date: Tue, 23 Jan 2018 16:52:45 +0000
+Subject: [PATCH] irqchip: irq-bcm2836: Remove regmap and syscon use
+
+The syscon node defines a register range that duplicates that used by
+the local_intc node on bcm2836/7. Since irq-bcm2835 and irq-bcm2836 are
+built in and always present together (both drivers are enabled by
+CONFIG_ARCH_BCM2835), it is possible to replace the syscon usage with a
+global variable that simplifies the code. Doing so does lose the
+locking provided by regmap, but as only one side is using the regmap
+interface (irq-bcm2835 uses readl and write) there is no loss of
+atomicity.
+
+See: https://github.com/raspberrypi/firmware/issues/926
+
+Signed-off-by: Phil Elwell <phil@raspberrypi.org>
+---
+ drivers/irqchip/irq-bcm2835.c | 32 ++++++++++++--------------------
+ drivers/irqchip/irq-bcm2836.c |  5 +++++
+ 2 files changed, 17 insertions(+), 20 deletions(-)
+
+--- a/drivers/irqchip/irq-bcm2835.c
++++ b/drivers/irqchip/irq-bcm2835.c
+@@ -50,8 +50,6 @@
+ #include <linux/of_irq.h>
+ #include <linux/irqchip.h>
+ #include <linux/irqdomain.h>
+-#include <linux/mfd/syscon.h>
+-#include <linux/regmap.h>
+ 
+ #include <asm/exception.h>
+ #include <asm/mach/irq.h>
+@@ -100,7 +98,7 @@ struct armctrl_ic {
+       void __iomem *enable[NR_BANKS];
+       void __iomem *disable[NR_BANKS];
+       struct irq_domain *domain;
+-      struct regmap *local_regmap;
++      void __iomem *local_base;
+ };
+ 
+ static struct armctrl_ic intc __read_mostly;
+@@ -137,24 +135,20 @@ static void armctrl_unmask_irq(struct ir
+       if (d->hwirq >= NUMBER_IRQS) {
+               if (num_online_cpus() > 1) {
+                       unsigned int data;
+-                      int ret;
+ 
+-                      if (!intc.local_regmap) {
+-                              pr_err("FIQ is disabled due to missing regmap\n");
++                      if (!intc.local_base) {
++                              pr_err("FIQ is disabled due to missing arm_local_intc\n");
+                               return;
+                       }
+ 
+-                      ret = regmap_read(intc.local_regmap,
+-                                        ARM_LOCAL_GPU_INT_ROUTING, &data);
+-                      if (ret) {
+-                              pr_err("Failed to read int routing %d\n", ret);
+-                              return;
+-                      }
++                      data = readl_relaxed(intc.local_base +
++                                           ARM_LOCAL_GPU_INT_ROUTING);
+ 
+                       data &= ~0xc;
+                       data |= (1 << 2);
+-                      regmap_write(intc.local_regmap,
+-                                   ARM_LOCAL_GPU_INT_ROUTING, data);
++                      writel_relaxed(data,
++                                     intc.local_base +
++                                     ARM_LOCAL_GPU_INT_ROUTING);
+               }
+ 
+               writel_relaxed(REG_FIQ_ENABLE | hwirq_to_fiq(d->hwirq),
+@@ -240,12 +234,10 @@ static int __init armctrl_of_init(struct
+       }
+ 
+       if (is_2836) {
+-              intc.local_regmap =
+-                      syscon_regmap_lookup_by_compatible("brcm,bcm2836-arm-local");
+-              if (IS_ERR(intc.local_regmap)) {
+-                      pr_err("Failed to get local register map. FIQ is disabled for cpus > 1\n");
+-                      intc.local_regmap = NULL;
+-              }
++              extern void __iomem * __attribute__((weak)) arm_local_intc;
++              intc.local_base = arm_local_intc;
++              if (!intc.local_base)
++                      pr_err("Failed to get local intc base. FIQ is disabled for cpus > 1\n");
+       }
+ 
+       /* Make a duplicate irq range which is used to enable FIQ */
+--- a/drivers/irqchip/irq-bcm2836.c
++++ b/drivers/irqchip/irq-bcm2836.c
+@@ -30,6 +30,9 @@ struct bcm2836_arm_irqchip_intc {
+ 
+ static struct bcm2836_arm_irqchip_intc intc  __read_mostly;
+ 
++void __iomem *arm_local_intc;
++EXPORT_SYMBOL_GPL(arm_local_intc);
++
+ static void bcm2836_arm_irqchip_mask_per_cpu_irq(unsigned int reg_offset,
+                                                unsigned int bit,
+                                                int cpu)
+@@ -234,6 +237,8 @@ static int __init bcm2836_arm_irqchip_l1
+               panic("%pOF: unable to map local interrupt registers\n", node);
+       }
+ 
++      arm_local_intc = intc.base;
++
+       bcm2835_init_local_timer_frequency();
+ 
+       intc.domain = irq_domain_add_linear(node, LAST_IRQ + 1,