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authorAdrian Schmutzler <freifunk@adrianschmutzler.de>2020-02-08 21:58:55 +0100
committerAdrian Schmutzler <freifunk@adrianschmutzler.de>2020-02-14 14:10:51 +0100
commit7d7aa2fd924c27829ec25f825481554dd81bce97 (patch)
tree658b87b89331670266163e522ea5fb52535633cb /target/linux/bcm27xx/patches-4.19/950-0790-dwc_otg-fiq_fsm-add-a-barrier-on-entry-into-FIQ-hand.patch
parente7bfda2c243e66a75ff966ba04c28b1590b5d24c (diff)
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brcm2708: rename target to bcm27xx
This change makes the names of Broadcom targets consistent by using the common notation based on SoC/CPU ID (which is used internally anyway), bcmXXXX instead of brcmXXXX. This is even used for target TITLE in make menuconfig already, only the short target name used brcm so far. Despite, since subtargets range from bcm2708 to bcm2711, it seems appropriate to use bcm27xx instead of bcm2708 (again, as already done for BOARDNAME). This also renames the packages brcm2708-userland and brcm2708-gpu-fw. Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de> Acked-by: Álvaro Fernández Rojas <noltari@gmail.com>
Diffstat (limited to 'target/linux/bcm27xx/patches-4.19/950-0790-dwc_otg-fiq_fsm-add-a-barrier-on-entry-into-FIQ-hand.patch')
-rw-r--r--target/linux/bcm27xx/patches-4.19/950-0790-dwc_otg-fiq_fsm-add-a-barrier-on-entry-into-FIQ-hand.patch49
1 files changed, 49 insertions, 0 deletions
diff --git a/target/linux/bcm27xx/patches-4.19/950-0790-dwc_otg-fiq_fsm-add-a-barrier-on-entry-into-FIQ-hand.patch b/target/linux/bcm27xx/patches-4.19/950-0790-dwc_otg-fiq_fsm-add-a-barrier-on-entry-into-FIQ-hand.patch
new file mode 100644
index 0000000000..dc48605cb1
--- /dev/null
+++ b/target/linux/bcm27xx/patches-4.19/950-0790-dwc_otg-fiq_fsm-add-a-barrier-on-entry-into-FIQ-hand.patch
@@ -0,0 +1,49 @@
+From b2d43d61a1d6d070664f10d12b3c8b6df11eb21d Mon Sep 17 00:00:00 2001
+From: Jonathan Bell <jonathan@raspberrypi.org>
+Date: Mon, 13 Jan 2020 15:54:55 +0000
+Subject: [PATCH] dwc_otg: fiq_fsm: add a barrier on entry into FIQ
+ handler(s)
+
+On BCM2835, there is no hardware guarantee that multiple outstanding
+reads to different peripherals will complete in-order. The FIQ code
+uses peripheral reads without barriers for performance, so in the case
+where a read to a slow peripheral was issued immediately prior to FIQ
+entry, the first peripheral read that the FIQ did could end up with
+wrong read data returned.
+
+Add dsb(sy) on entry so that all outstanding reads are retired.
+
+The FIQ only issues reads to the dwc_otg core, so per-read barriers
+in the handler itself are not required.
+
+On BCM2836 and BCM2837 the barrier is not strictly required due to
+differences in how the peripheral bus is implemented, but having
+arch-specific handlers that introduce different latencies is risky.
+
+Signed-off-by: Jonathan Bell <jonathan@raspberrypi.org>
+---
+ drivers/usb/host/dwc_otg/dwc_otg_fiq_fsm.c | 6 ++++++
+ 1 file changed, 6 insertions(+)
+
+--- a/drivers/usb/host/dwc_otg/dwc_otg_fiq_fsm.c
++++ b/drivers/usb/host/dwc_otg/dwc_otg_fiq_fsm.c
+@@ -1259,6 +1259,9 @@ void notrace dwc_otg_fiq_fsm(struct fiq_
+ haintmsk_data_t haintmsk;
+ int kick_irq = 0;
+
++ /* Ensure peripheral reads issued prior to FIQ entry are complete */
++ dsb(sy);
++
+ gintsts_handled.d32 = 0;
+ haint_handled.d32 = 0;
+
+@@ -1379,6 +1382,9 @@ void notrace dwc_otg_fiq_nop(struct fiq_
+ gintmsk_data_t gintmsk;
+ hfnum_data_t hfnum;
+
++ /* Ensure peripheral reads issued prior to FIQ entry are complete */
++ dsb(sy);
++
+ fiq_fsm_spin_lock(&state->lock);
+ hfnum.d32 = FIQ_READ(state->dwc_regs_base + HFNUM);
+ gintsts.d32 = FIQ_READ(state->dwc_regs_base + GINTSTS);