When the patch was originally introduced [0], it claimed that on mt7621, CPU core 1 came up with a bad BogoMIPS value because the clock needed time to stabilize. That is not the case today, at least on my Ubiquity EdgeRouter X device. As evident from messages below, the LPJ value is already correct after the original delay loop calibration.
Original calibration: [ 0.033728] Calibrating delay loop... 583.68 BogoMIPS (lpj=1167360) Redundant re-calibration (this patch removes it): [ 0.788770] 4 CPUs re-calibrate udelay(lpj = 1167360) So, remove the re-calibration patch to avoid extra busy looping to come up with the exact same lpj value. This patch also disables CONFIG_GENERIC_CLOCKEVENTS_BROADCAST as it does not seem necessary for mt7621 - ER-X boots and functions correctly without that symbol and no other ramips targets enable it. This change is only for Linux 5.10, it does not affect Linux 5.4 builds. Lastly, refresh existing patches to account for the removal of the re-calibration logic. [0]: 6acb53c52 ("ralink: fix rcu_sched stalls on mt7621") Signed-off-by: Ilya Lipnitskiy <ilya.lipnits...@gmail.com> Cc: John Crispin <j...@phrozen.org> --- target/linux/ramips/mt7621/config-5.10 | 1 - .../patches-5.10/321-mt7621-timer.patch | 87 ------------------- .../322-mt7621-fix-cpu-clk-add-clkdev.patch | 10 +-- .../323-mt7621-memory-detect.patch | 10 +-- 4 files changed, 10 insertions(+), 98 deletions(-) delete mode 100644 target/linux/ramips/patches-5.10/321-mt7621-timer.patch diff --git a/target/linux/ramips/mt7621/config-5.10 b/target/linux/ramips/mt7621/config-5.10 index 430ea9513c..1f319da5aa 100644 --- a/target/linux/ramips/mt7621/config-5.10 +++ b/target/linux/ramips/mt7621/config-5.10 @@ -61,7 +61,6 @@ CONFIG_FIXED_PHY=y CONFIG_FW_LOADER_PAGED_BUF=y CONFIG_GENERIC_ATOMIC64=y CONFIG_GENERIC_CLOCKEVENTS=y -CONFIG_GENERIC_CLOCKEVENTS_BROADCAST=y CONFIG_GENERIC_CMOS_UPDATE=y CONFIG_GENERIC_CPU_AUTOPROBE=y CONFIG_GENERIC_GETTIMEOFDAY=y diff --git a/target/linux/ramips/patches-5.10/321-mt7621-timer.patch b/target/linux/ramips/patches-5.10/321-mt7621-timer.patch deleted file mode 100644 index 91e14ad63b..0000000000 --- a/target/linux/ramips/patches-5.10/321-mt7621-timer.patch +++ /dev/null @@ -1,87 +0,0 @@ ---- a/arch/mips/ralink/mt7621.c -+++ b/arch/mips/ralink/mt7621.c -@@ -9,6 +9,7 @@ - #include <linux/init.h> - #include <linux/slab.h> - #include <linux/sys_soc.h> -+#include <linux/jiffies.h> - - #include <asm/mipsregs.h> - #include <asm/smp-ops.h> -@@ -16,6 +17,7 @@ - #include <asm/mach-ralink/ralink_regs.h> - #include <asm/mach-ralink/mt7621.h> - #include <asm/mips-boards/launch.h> -+#include <asm/delay.h> - - #include <pinmux.h> - -@@ -161,6 +163,58 @@ bool plat_cpu_core_present(int core) - return true; - } - -+#define LPS_PREC 8 -+/* -+* Re-calibration lpj(loop-per-jiffy). -+* (derived from kernel/calibrate.c) -+*/ -+static int udelay_recal(void) -+{ -+ unsigned int i, lpj = 0; -+ unsigned long ticks, loopbit; -+ int lps_precision = LPS_PREC; -+ -+ lpj = (1<<12); -+ -+ while ((lpj <<= 1) != 0) { -+ /* wait for "start of" clock tick */ -+ ticks = jiffies; -+ while (ticks == jiffies) -+ /* nothing */; -+ -+ /* Go .. */ -+ ticks = jiffies; -+ __delay(lpj); -+ ticks = jiffies - ticks; -+ if (ticks) -+ break; -+ } -+ -+ /* -+ * Do a binary approximation to get lpj set to -+ * equal one clock (up to lps_precision bits) -+ */ -+ lpj >>= 1; -+ loopbit = lpj; -+ while (lps_precision-- && (loopbit >>= 1)) { -+ lpj |= loopbit; -+ ticks = jiffies; -+ while (ticks == jiffies) -+ /* nothing */; -+ ticks = jiffies; -+ __delay(lpj); -+ if (jiffies != ticks) /* longer than 1 tick */ -+ lpj &= ~loopbit; -+ } -+ printk(KERN_INFO "%d CPUs re-calibrate udelay(lpj = %d)\n", NR_CPUS, lpj); -+ -+ for(i=0; i< NR_CPUS; i++) -+ cpu_data[i].udelay_val = lpj; -+ -+ return 0; -+} -+device_initcall(udelay_recal); -+ - void prom_soc_init(struct ralink_soc_info *soc_info) - { - void __iomem *sysc = (void __iomem *) KSEG1ADDR(MT7621_SYSC_BASE); ---- a/arch/mips/ralink/Kconfig -+++ b/arch/mips/ralink/Kconfig -@@ -63,6 +63,7 @@ choice - select HAVE_PCI if PCI_MT7621 - select SOC_BUS - select WEAK_REORDERING_BEYOND_LLSC -+ select GENERIC_CLOCKEVENTS_BROADCAST - endchoice - - choice diff --git a/target/linux/ramips/patches-5.10/322-mt7621-fix-cpu-clk-add-clkdev.patch b/target/linux/ramips/patches-5.10/322-mt7621-fix-cpu-clk-add-clkdev.patch index 723c628790..be5fee54b2 100644 --- a/target/linux/ramips/patches-5.10/322-mt7621-fix-cpu-clk-add-clkdev.patch +++ b/target/linux/ramips/patches-5.10/322-mt7621-fix-cpu-clk-add-clkdev.patch @@ -36,10 +36,10 @@ #define MT7621_DDR2_SIZE_MAX 256 --- a/arch/mips/ralink/mt7621.c +++ b/arch/mips/ralink/mt7621.c -@@ -10,6 +10,10 @@ +@@ -9,6 +9,10 @@ + #include <linux/init.h> #include <linux/slab.h> #include <linux/sys_soc.h> - #include <linux/jiffies.h> +#include <linux/clk.h> +#include <linux/clkdev.h> +#include <linux/clk-provider.h> @@ -47,15 +47,15 @@ #include <asm/mipsregs.h> #include <asm/smp-ops.h> -@@ -18,6 +22,7 @@ +@@ -16,6 +20,7 @@ + #include <asm/mach-ralink/ralink_regs.h> #include <asm/mach-ralink/mt7621.h> #include <asm/mips-boards/launch.h> - #include <asm/delay.h> +#include <asm/time.h> #include <pinmux.h> -@@ -108,11 +113,89 @@ static struct rt2880_pmx_group mt7621_pi +@@ -106,11 +111,89 @@ static struct rt2880_pmx_group mt7621_pi { 0 } }; diff --git a/target/linux/ramips/patches-5.10/323-mt7621-memory-detect.patch b/target/linux/ramips/patches-5.10/323-mt7621-memory-detect.patch index 07c7588661..9f80d02638 100644 --- a/target/linux/ramips/patches-5.10/323-mt7621-memory-detect.patch +++ b/target/linux/ramips/patches-5.10/323-mt7621-memory-detect.patch @@ -44,10 +44,10 @@ Signed-off-by: Chuanhong Guo <gch981...@gmail.com> #define MT7621_CHIP_NAME1 0x20203132 --- a/arch/mips/ralink/mt7621.c +++ b/arch/mips/ralink/mt7621.c -@@ -10,11 +10,13 @@ +@@ -9,11 +9,13 @@ + #include <linux/init.h> #include <linux/slab.h> #include <linux/sys_soc.h> - #include <linux/jiffies.h> +#include <linux/memblock.h> #include <linux/clk.h> #include <linux/clkdev.h> @@ -58,7 +58,7 @@ Signed-off-by: Chuanhong Guo <gch981...@gmail.com> #include <asm/mipsregs.h> #include <asm/smp-ops.h> #include <asm/mips-cps.h> -@@ -57,6 +59,8 @@ +@@ -55,6 +57,8 @@ #define MT7621_GPIO_MODE_SDHCI_SHIFT 18 #define MT7621_GPIO_MODE_SDHCI_GPIO 1 @@ -67,7 +67,7 @@ Signed-off-by: Chuanhong Guo <gch981...@gmail.com> static struct rt2880_pmx_func uart1_grp[] = { FUNC("uart1", 0, 1, 2) }; static struct rt2880_pmx_func i2c_grp[] = { FUNC("i2c", 0, 3, 2) }; static struct rt2880_pmx_func uart3_grp[] = { -@@ -141,6 +145,26 @@ static struct clk *__init mt7621_add_sys +@@ -139,6 +143,26 @@ static struct clk *__init mt7621_add_sys return clk; } @@ -94,7 +94,7 @@ Signed-off-by: Chuanhong Guo <gch981...@gmail.com> void __init ralink_clk_init(void) { u32 syscfg, xtal_sel, clkcfg, clk_sel, curclk, ffiv, ffrac; -@@ -346,10 +370,7 @@ void prom_soc_init(struct ralink_soc_inf +@@ -292,10 +316,7 @@ void prom_soc_init(struct ralink_soc_inf (rev >> CHIP_REV_VER_SHIFT) & CHIP_REV_VER_MASK, (rev & CHIP_REV_ECO_MASK)); -- 2.30.1 _______________________________________________ openwrt-devel mailing list openwrt-devel@lists.openwrt.org https://lists.openwrt.org/mailman/listinfo/openwrt-devel