diff options
Diffstat (limited to 'target/linux/tegra/patches-5.4')
2 files changed, 0 insertions, 123 deletions
diff --git a/target/linux/tegra/patches-5.4/100-serial8250-on-tegra-hsuart-recover-from-spurious-interrupts-due-to-tegra2-silicon-bug.patch b/target/linux/tegra/patches-5.4/100-serial8250-on-tegra-hsuart-recover-from-spurious-interrupts-due-to-tegra2-silicon-bug.patch deleted file mode 100644 index 08ed9d441c..0000000000 --- a/target/linux/tegra/patches-5.4/100-serial8250-on-tegra-hsuart-recover-from-spurious-interrupts-due-to-tegra2-silicon-bug.patch +++ /dev/null @@ -1,77 +0,0 @@ -From patchwork Fri Jul 13 11:32:42 2018 -Content-Type: text/plain; charset="utf-8" -MIME-Version: 1.0 -Content-Transfer-Encoding: 7bit -Subject: serial8250 on tegra hsuart: recover from spurious interrupts due to - tegra2 silicon bug -X-Patchwork-Submitter: "David R. Piegdon" <lkml@p23q.org> -X-Patchwork-Id: 943440 -Message-Id: <4676ea34-69ce-5422-1ded-94218b89f7d9@p23q.org> -To: linux-tegra@vger.kernel.org -Date: Fri, 13 Jul 2018 11:32:42 +0000 -From: "David R. Piegdon" <lkml@p23q.org> -List-Id: <linux-tegra.vger.kernel.org> - -Hi, -a while back I sent a few mails regarding spurious interrupts in the -UARTA (hsuart) block of the Tegra2 SoC, when using the 8250 driver for -it instead of the hsuart driver. After going down a pretty deep -debugging/testing hole, I think I found a patch that fixes the issue. So -far testing in a reboot-cycle suggests that the error frequency dropped -from >3% of all reboots to at least <0.05% of all reboots. Tests -continue to run over the weekend. - -The patch below already is a second iteration; the first did not reset -the MCR or contain the lines below '// clear interrupts'. This resulted -in no more spurious interrupts, but in a few % of spurious interrupts -that were recovered the UART block did not receive any characters any -more. So further resetting was required to fully reacquire operational -state of the UART block. - -I'd love any comments/suggestions on this! - -Cheers, - -David - ---- a/drivers/tty/serial/8250/8250_core.c -+++ b/drivers/tty/serial/8250/8250_core.c -@@ -133,6 +133,38 @@ static irqreturn_t serial8250_interrupt( - - if (l == i->head && pass_counter++ > PASS_LIMIT) - break; -+ -+#ifdef CONFIG_ARCH_TEGRA_2x_SOC -+ if (!handled && (port->type == PORT_TEGRA)) { -+ /* -+ * Fix Tegra 2 CPU silicon bug where sometimes -+ * "TX holding register empty" interrupts result in a -+ * bad (metastable?) state in Tegras HSUART IP core. -+ * Only way to recover seems to be to reset all -+ * interrupts as well as the TX queue and the MCR. -+ * But we don't want to loose any outgoing characters, -+ * so only do it if the RX and TX queues are empty. -+ */ -+ unsigned char lsr = port->serial_in(port, UART_LSR); -+ const unsigned char fifo_empty_mask = -+ (UART_LSR_TEMT | UART_LSR_THRE); -+ if (((lsr & (UART_LSR_DR | fifo_empty_mask)) == -+ fifo_empty_mask)) { -+ port->serial_out(port, UART_IER, 0); -+ port->serial_out(port, UART_MCR, 0); -+ serial8250_clear_and_reinit_fifos(up); -+ port->serial_out(port, UART_MCR, up->mcr); -+ port->serial_out(port, UART_IER, up->ier); -+ // clear interrupts -+ serial_port_in(port, UART_LSR); -+ serial_port_in(port, UART_RX); -+ serial_port_in(port, UART_IIR); -+ serial_port_in(port, UART_MSR); -+ up->lsr_saved_flags = 0; -+ up->msr_saved_flags = 0; -+ } -+ } -+#endif - } while (l != end); - - spin_unlock(&i->lock); diff --git a/target/linux/tegra/patches-5.4/101-ARM-dtc-tegra-enable-front-panel-leds-in-TrimSlice.patch b/target/linux/tegra/patches-5.4/101-ARM-dtc-tegra-enable-front-panel-leds-in-TrimSlice.patch deleted file mode 100644 index ae48e8d862..0000000000 --- a/target/linux/tegra/patches-5.4/101-ARM-dtc-tegra-enable-front-panel-leds-in-TrimSlice.patch +++ /dev/null @@ -1,46 +0,0 @@ ---- a/arch/arm/boot/dts/tegra20-trimslice.dts -+++ b/arch/arm/boot/dts/tegra20-trimslice.dts -@@ -200,16 +200,17 @@ - conf_ata { - nvidia,pins = "ata", "atc", "atd", "ate", - "crtp", "dap2", "dap3", "dap4", "dta", -- "dtb", "dtc", "dtd", "dte", "gmb", -- "gme", "i2cp", "pta", "slxc", "slxd", -- "spdi", "spdo", "uda"; -+ "dtb", "dtc", "dtd", "gmb", "gme", -+ "i2cp", "pta", "slxc", "slxd", "spdi", -+ "spdo", "uda"; - nvidia,pull = <TEGRA_PIN_PULL_NONE>; - nvidia,tristate = <TEGRA_PIN_ENABLE>; - }; - conf_atb { - nvidia,pins = "atb", "cdev1", "cdev2", "dap1", -- "gma", "gmc", "gmd", "gpu", "gpu7", -- "gpv", "sdio1", "slxa", "slxk", "uac"; -+ "dte", "gma", "gmc", "gmd", "gpu", -+ "gpu7", "gpv", "sdio1", "slxa", "slxk", -+ "uac"; - nvidia,pull = <TEGRA_PIN_PULL_NONE>; - nvidia,tristate = <TEGRA_PIN_DISABLE>; - }; -@@ -402,6 +403,20 @@ - }; - }; - -+ gpio-leds { -+ compatible = "gpio-leds"; -+ -+ ds2 { -+ label = "trimslice:green:right"; -+ gpios = <&gpio TEGRA_GPIO(D, 2) GPIO_ACTIVE_LOW>; -+ }; -+ -+ ds3 { -+ label = "trimslice:green:left"; -+ gpios = <&gpio TEGRA_GPIO(BB, 5) GPIO_ACTIVE_LOW>; -+ }; -+ }; -+ - poweroff { - compatible = "gpio-poweroff"; - gpios = <&gpio TEGRA_GPIO(X, 7) GPIO_ACTIVE_LOW>; |