[PATCH v8 0/5] add TCB driver for sama5d2

When booting under OP-TEE, the SYSC is secured which means the PIT is also not accessible by non-secure world. The TCB 0 however is always available for non-secure world and thus can be used. This series add a TCB driver and enables it in sama5d2 configs.
--- Changes in v8: - Switch clock to use t0_clk, generated clk does not works if parent clock is slow_ck. Moreover, tcb0_clk needs to be enabled for the TCB to operate correctly - Change driver to use TCB_CMR_TIMER_CLOCK2 (tcb0_clk / 8) - Add potential missing clk_enable() - Add u-boot,dm-pre-reloc properties to TCB nodes and to its dependencies in order to be used in SPL
Changes in v7: - Keep the exact same Linux aic node definition - Fixed a few constant definition to use (1 << x)
Changes in V6: - Fix node ordering in device tree - Disable CONFIG_PIT_TIMER in sama5d2 configuration file - Fixed mach-at91/armv7/Makefile to allow building with TCB
Changes in v5: - Fixed missing include in .dts file for IRQ defines - Add aic interrupt controller node to avoid DTC warnings
Changes in v4: - Add missing interrupts property to tcb node
Changes in v3: - Remove useless defines - Add printf in case of unsupported timers specified in device-tree - Add "syscon" compatible to tcb node
Changes in v2: - Reworked driver to use existing Linux bindings
Clément Léger (5): timer: atmel_tcb_timer: add atmel_tcb driver ARM: dts: at91: sama5d2: add AIC node ARM: dts: at91: sama5d2: add TCB node ARM: dts: at91: sama5d2: add u-boot,dm-pre-reloc property for TCB configs: sama5d2: enable option CONFIG_ATMEL_TCB_TIMER
MAINTAINERS | 1 + arch/arm/dts/sama5d2.dtsi | 28 ++++ arch/arm/mach-at91/armv7/Makefile | 2 + configs/sama5d2_icp_mmc_defconfig | 2 +- configs/sama5d2_ptc_ek_mmc_defconfig | 2 +- configs/sama5d2_ptc_ek_nandflash_defconfig | 2 +- configs/sama5d2_xplained_emmc_defconfig | 2 +- configs/sama5d2_xplained_mmc_defconfig | 2 +- configs/sama5d2_xplained_qspiflash_defconfig | 2 +- configs/sama5d2_xplained_spiflash_defconfig | 2 +- drivers/timer/Kconfig | 8 + drivers/timer/Makefile | 1 + drivers/timer/atmel_tcb_timer.c | 161 +++++++++++++++++++ 13 files changed, 208 insertions(+), 7 deletions(-) create mode 100644 drivers/timer/atmel_tcb_timer.c

Add a driver for the timer counter block that can be found on sama5d2. This driver will be used when booting under OP-TEE since the pit timer which is part of the SYSC is secured. Channel 1 & 2 are configured to be chained together which allows to have a 64bits counter.
Reviewed-by: Claudiu Beznea claudiu.beznea@microchip.com Signed-off-by: Clément Léger clement.leger@bootlin.com --- MAINTAINERS | 1 + arch/arm/mach-at91/armv7/Makefile | 2 + drivers/timer/Kconfig | 8 ++ drivers/timer/Makefile | 1 + drivers/timer/atmel_tcb_timer.c | 161 ++++++++++++++++++++++++++++++ 5 files changed, 173 insertions(+) create mode 100644 drivers/timer/atmel_tcb_timer.c
diff --git a/MAINTAINERS b/MAINTAINERS index 0f39bc6bc9..e30389dc3e 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -352,6 +352,7 @@ F: arch/arm/mach-at91/ F: board/atmel/ F: drivers/cpu/at91_cpu.c F: drivers/misc/microchip_flexcom.c +F: drivers/timer/atmel_tcb_timer.c F: include/dt-bindings/mfd/atmel-flexcom.h F: drivers/timer/mchp-pit64b-timer.c
diff --git a/arch/arm/mach-at91/armv7/Makefile b/arch/arm/mach-at91/armv7/Makefile index 246050b67b..f395b55c3d 100644 --- a/arch/arm/mach-at91/armv7/Makefile +++ b/arch/arm/mach-at91/armv7/Makefile @@ -14,9 +14,11 @@ obj-y += cpu.o ifndef CONFIG_$(SPL_TPL_)SYSRESET obj-y += reset.o endif +ifneq ($(CONFIG_ATMEL_TCB_TIMER),y) ifneq ($(CONFIG_ATMEL_PIT_TIMER),y) ifneq ($(CONFIG_MCHP_PIT64B_TIMER),y) # old non-DM timer driver obj-y += timer.o endif endif +endif diff --git a/drivers/timer/Kconfig b/drivers/timer/Kconfig index 8913142654..8fad59b81a 100644 --- a/drivers/timer/Kconfig +++ b/drivers/timer/Kconfig @@ -96,6 +96,14 @@ config ATMEL_PIT_TIMER it is designed to offer maximum accuracy and efficient management, even for systems with long response time.
+config ATMEL_TCB_TIMER + bool "Atmel timer counter support" + depends on TIMER + depends on ARCH_AT91 + help + Select this to enable the use of the timer counter as a monotonic + counter. + config CADENCE_TTC_TIMER bool "Cadence TTC (Triple Timer Counter)" depends on TIMER diff --git a/drivers/timer/Makefile b/drivers/timer/Makefile index e2bd530eb0..58da6c1e84 100644 --- a/drivers/timer/Makefile +++ b/drivers/timer/Makefile @@ -10,6 +10,7 @@ obj-$(CONFIG_ARC_TIMER) += arc_timer.o obj-$(CONFIG_AST_TIMER) += ast_timer.o obj-$(CONFIG_ATCPIT100_TIMER) += atcpit100_timer.o obj-$(CONFIG_ATMEL_PIT_TIMER) += atmel_pit_timer.o +obj-$(CONFIG_ATMEL_TCB_TIMER) += atmel_tcb_timer.o obj-$(CONFIG_CADENCE_TTC_TIMER) += cadence-ttc.o obj-$(CONFIG_DESIGNWARE_APB_TIMER) += dw-apb-timer.o obj-$(CONFIG_MPC83XX_TIMER) += mpc83xx_timer.o diff --git a/drivers/timer/atmel_tcb_timer.c b/drivers/timer/atmel_tcb_timer.c new file mode 100644 index 0000000000..8c17987c7d --- /dev/null +++ b/drivers/timer/atmel_tcb_timer.c @@ -0,0 +1,161 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2022 Microchip Corporation + * + * Author: Clément Léger clement.leger@bootlin.com + */ + +#include <common.h> +#include <clk.h> +#include <dm.h> +#include <timer.h> +#include <asm/io.h> +#include <linux/bitops.h> + +#define TCB_CHAN(chan) ((chan) * 0x40) + +#define TCB_CCR(chan) (0x0 + TCB_CHAN(chan)) +#define TCB_CCR_CLKEN (1 << 0) + +#define TCB_CMR(chan) (0x4 + TCB_CHAN(chan)) +#define TCB_CMR_WAVE (1 << 15) +#define TCB_CMR_TIMER_CLOCK2 1 +#define TCB_CMR_XC1 6 +#define TCB_CMR_ACPA_SET (1 << 16) +#define TCB_CMR_ACPC_CLEAR (2 << 18) + +#define TCB_CV(chan) (0x10 + TCB_CHAN(chan)) + +#define TCB_RA(chan) (0x14 + TCB_CHAN(chan)) +#define TCB_RC(chan) (0x1c + TCB_CHAN(chan)) + +#define TCB_IDR(chan) (0x28 + TCB_CHAN(chan)) + +#define TCB_BCR 0xc0 +#define TCB_BCR_SYNC (1 << 0) + +#define TCB_BMR 0xc4 +#define TCB_BMR_TC1XC1S_TIOA0 (2 << 2) + +#define TCB_WPMR 0xe4 +#define TCB_WPMR_WAKEY 0x54494d + +#define TCB_CLK_DIVISOR 8 +struct atmel_tcb_plat { + void __iomem *base; +}; + +static u64 atmel_tcb_get_count(struct udevice *dev) +{ + struct atmel_tcb_plat *plat = dev_get_plat(dev); + u64 cv0 = 0; + u64 cv1 = 0; + + do { + cv1 = readl(plat->base + TCB_CV(1)); + cv0 = readl(plat->base + TCB_CV(0)); + } while (readl(plat->base + TCB_CV(1)) != cv1); + + cv0 |= cv1 << 32; + + return cv0; +} + +static void atmel_tcb_configure(void __iomem *base) +{ + /* Disable write protection */ + writel(TCB_WPMR_WAKEY, base + TCB_WPMR); + + /* Disable all irqs for both channel 0 & 1 */ + writel(0xff, base + TCB_IDR(0)); + writel(0xff, base + TCB_IDR(1)); + + /* + * In order to avoid wrapping, use a 64 bit counter by chaining + * two channels. + * Channel 0 is configured to generate a clock on TIOA0 which is cleared + * when reaching 0x80000000 and set when reaching 0. + */ + writel(TCB_CMR_TIMER_CLOCK2 | TCB_CMR_WAVE | TCB_CMR_ACPA_SET + | TCB_CMR_ACPC_CLEAR, base + TCB_CMR(0)); + writel(0x80000000, base + TCB_RC(0)); + writel(0x1, base + TCB_RA(0)); + writel(TCB_CCR_CLKEN, base + TCB_CCR(0)); + + /* Channel 1 is configured to use TIOA0 as input */ + writel(TCB_CMR_XC1 | TCB_CMR_WAVE, base + TCB_CMR(1)); + writel(TCB_CCR_CLKEN, base + TCB_CCR(1)); + + /* Set XC1 input to be TIOA0 (ie output of Channel 0) */ + writel(TCB_BMR_TC1XC1S_TIOA0, base + TCB_BMR); + + /* Sync & start all timers */ + writel(TCB_BCR_SYNC, base + TCB_BCR); +} + +static int atmel_tcb_probe(struct udevice *dev) +{ + struct atmel_tcb_plat *plat = dev_get_plat(dev); + struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev); + struct clk clk; + ulong clk_rate; + int ret; + + if (!device_is_compatible(dev->parent, "atmel,sama5d2-tcb")) + return -EINVAL; + + /* Currently, we only support channel 0 and 1 to be chained */ + if (dev_read_addr_index(dev, 0) != 0 && + dev_read_addr_index(dev, 1) != 1) { + printf("Error: only chained timers 0 and 1 are supported\n"); + return -EINVAL; + } + + ret = clk_get_by_name(dev->parent, "t0_clk", &clk); + if (ret) + return -EINVAL; + + ret = clk_enable(&clk); + if (ret) + return ret; + + clk_rate = clk_get_rate(&clk); + if (!clk_rate) { + clk_disable(&clk); + return -EINVAL; + } + + uc_priv->clock_rate = clk_rate / TCB_CLK_DIVISOR; + + atmel_tcb_configure(plat->base); + + return 0; +} + +static int atmel_tcb_of_to_plat(struct udevice *dev) +{ + struct atmel_tcb_plat *plat = dev_get_plat(dev); + + plat->base = dev_read_addr_ptr(dev->parent); + + return 0; +} + +static const struct timer_ops atmel_tcb_ops = { + .get_count = atmel_tcb_get_count, +}; + +static const struct udevice_id atmel_tcb_ids[] = { + { .compatible = "atmel,tcb-timer" }, + { } +}; + +U_BOOT_DRIVER(atmel_tcb) = { + .name = "atmel_tcb", + .id = UCLASS_TIMER, + .of_match = atmel_tcb_ids, + .of_to_plat = atmel_tcb_of_to_plat, + .plat_auto = sizeof(struct atmel_tcb_plat), + .probe = atmel_tcb_probe, + .ops = &atmel_tcb_ops, +};

When using interrupts property, a global interrupt controller needs to be added to avoid warnings when compiling device-tree:
arch/arm/dts/at91-sama5d2_xplained.dtb: Warning (interrupts_property): /ahb/apb/timer@f800c000: Missing interrupt-parent
Add AIC node as the sama5d2 global interrupt controller.
Signed-off-by: Clément Léger clement.leger@bootlin.com --- arch/arm/dts/sama5d2.dtsi | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/arch/arm/dts/sama5d2.dtsi b/arch/arm/dts/sama5d2.dtsi index 038cd73c03..7de58e4a1f 100644 --- a/arch/arm/dts/sama5d2.dtsi +++ b/arch/arm/dts/sama5d2.dtsi @@ -3,6 +3,7 @@ / { model = "Atmel SAMA5D2 family SoC"; compatible = "atmel,sama5d2"; + interrupt-parent = <&aic>;
aliases { spi0 = &spi0; @@ -762,6 +763,14 @@ status = "disabled"; };
+ aic: interrupt-controller@fc020000 { + #interrupt-cells = <3>; + compatible = "atmel,sama5d2-aic"; + interrupt-controller; + reg = <0xfc020000 0x200>; + atmel,external-irqs = <49>; + }; + i2c1: i2c@fc028000 { compatible = "atmel,sama5d2-i2c"; reg = <0xfc028000 0x100>;

Add the device-tree node to describe the TCB timer.
Signed-off-by: Clément Léger clement.leger@bootlin.com --- arch/arm/dts/sama5d2.dtsi | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)
diff --git a/arch/arm/dts/sama5d2.dtsi b/arch/arm/dts/sama5d2.dtsi index 7de58e4a1f..058009adca 100644 --- a/arch/arm/dts/sama5d2.dtsi +++ b/arch/arm/dts/sama5d2.dtsi @@ -1,4 +1,5 @@ #include "skeleton.dtsi" +#include <dt-bindings/interrupt-controller/irq.h>
/ { model = "Atmel SAMA5D2 family SoC"; @@ -639,6 +640,21 @@ status = "disabled"; };
+ tcb0: timer@f800c000 { + compatible = "atmel,sama5d2-tcb", "simple-mfd", "syscon"; + reg = <0xf800c000 0x100>; + interrupts = <35 IRQ_TYPE_LEVEL_HIGH 0>; + clocks = <&tcb0_clk>, <&tcb0_gclk>, <&clk32k>; + clock-names = "t0_clk", "gclk", "slow_clk"; + #address-cells = <1>; + #size-cells = <0>; + + timer0: timer@0 { + compatible = "atmel,tcb-timer"; + reg = <0>, <1>; + }; + }; + uart0: serial@f801c000 { compatible = "atmel,at91sam9260-usart"; reg = <0xf801c000 0x100>;

In order to use the TCB early in boot and in the SPL, add u-boot,dm-pre-reloc property for the TCB and the clock that is used by the driver (tcb0_clk).
Signed-off-by: Clément Léger clement.leger@bootlin.com --- arch/arm/dts/sama5d2.dtsi | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/arch/arm/dts/sama5d2.dtsi b/arch/arm/dts/sama5d2.dtsi index 058009adca..d92bdd5588 100644 --- a/arch/arm/dts/sama5d2.dtsi +++ b/arch/arm/dts/sama5d2.dtsi @@ -363,6 +363,7 @@ #clock-cells = <0>; reg = <35>; atmel,clk-output-range = <0 83000000>; + u-boot,dm-pre-reloc; };
tcb1_clk: tcb1_clk@36 { @@ -648,10 +649,12 @@ clock-names = "t0_clk", "gclk", "slow_clk"; #address-cells = <1>; #size-cells = <0>; + u-boot,dm-pre-reloc;
timer0: timer@0 { compatible = "atmel,tcb-timer"; reg = <0>, <1>; + u-boot,dm-pre-reloc; }; };

Enable CONFIG_ATMEL_TCB_TIMER and disable CONFIG_ATMEL_PIT_TIMER. This will allow using the TCB timer instead of the PIT one when running under OP-TEE.
Reviewed-by: Claudiu Beznea claudiu.beznea@microchip.com Signed-off-by: Clément Léger clement.leger@bootlin.com --- configs/sama5d2_icp_mmc_defconfig | 2 +- configs/sama5d2_ptc_ek_mmc_defconfig | 2 +- configs/sama5d2_ptc_ek_nandflash_defconfig | 2 +- configs/sama5d2_xplained_emmc_defconfig | 2 +- configs/sama5d2_xplained_mmc_defconfig | 2 +- configs/sama5d2_xplained_qspiflash_defconfig | 2 +- configs/sama5d2_xplained_spiflash_defconfig | 2 +- 7 files changed, 7 insertions(+), 7 deletions(-)
diff --git a/configs/sama5d2_icp_mmc_defconfig b/configs/sama5d2_icp_mmc_defconfig index 7761a57e0c..c035d7aad8 100644 --- a/configs/sama5d2_icp_mmc_defconfig +++ b/configs/sama5d2_icp_mmc_defconfig @@ -82,6 +82,6 @@ CONFIG_DEBUG_UART_ANNOUNCE=y CONFIG_ATMEL_USART=y CONFIG_TIMER=y CONFIG_SPL_TIMER=y -CONFIG_ATMEL_PIT_TIMER=y +CONFIG_ATMEL_TCB_TIMER=y CONFIG_OF_LIBFDT_OVERLAY=y # CONFIG_EFI_LOADER_HII is not set diff --git a/configs/sama5d2_ptc_ek_mmc_defconfig b/configs/sama5d2_ptc_ek_mmc_defconfig index 9f458e100b..7cb5ba37f6 100644 --- a/configs/sama5d2_ptc_ek_mmc_defconfig +++ b/configs/sama5d2_ptc_ek_mmc_defconfig @@ -71,7 +71,7 @@ CONFIG_DM_SERIAL=y CONFIG_DEBUG_UART_ANNOUNCE=y CONFIG_ATMEL_USART=y CONFIG_TIMER=y -CONFIG_ATMEL_PIT_TIMER=y +CONFIG_ATMEL_TCB_TIMER=y CONFIG_USB=y CONFIG_USB_EHCI_HCD=y CONFIG_USB_STORAGE=y diff --git a/configs/sama5d2_ptc_ek_nandflash_defconfig b/configs/sama5d2_ptc_ek_nandflash_defconfig index 6460ff3dad..667a10e93f 100644 --- a/configs/sama5d2_ptc_ek_nandflash_defconfig +++ b/configs/sama5d2_ptc_ek_nandflash_defconfig @@ -71,7 +71,7 @@ CONFIG_DM_SERIAL=y CONFIG_DEBUG_UART_ANNOUNCE=y CONFIG_ATMEL_USART=y CONFIG_TIMER=y -CONFIG_ATMEL_PIT_TIMER=y +CONFIG_ATMEL_TCB_TIMER=y CONFIG_USB=y CONFIG_USB_EHCI_HCD=y CONFIG_USB_STORAGE=y diff --git a/configs/sama5d2_xplained_emmc_defconfig b/configs/sama5d2_xplained_emmc_defconfig index 844a9cde64..72544b65bb 100644 --- a/configs/sama5d2_xplained_emmc_defconfig +++ b/configs/sama5d2_xplained_emmc_defconfig @@ -90,7 +90,7 @@ CONFIG_DM_SPI=y CONFIG_ATMEL_QSPI=y CONFIG_TIMER=y CONFIG_SPL_TIMER=y -CONFIG_ATMEL_PIT_TIMER=y +CONFIG_ATMEL_TCB_TIMER=y CONFIG_USB=y CONFIG_USB_EHCI_HCD=y CONFIG_USB_STORAGE=y diff --git a/configs/sama5d2_xplained_mmc_defconfig b/configs/sama5d2_xplained_mmc_defconfig index 0de0636587..bcdb84ce2c 100644 --- a/configs/sama5d2_xplained_mmc_defconfig +++ b/configs/sama5d2_xplained_mmc_defconfig @@ -92,7 +92,7 @@ CONFIG_DM_SPI=y CONFIG_ATMEL_QSPI=y CONFIG_TIMER=y CONFIG_SPL_TIMER=y -CONFIG_ATMEL_PIT_TIMER=y +CONFIG_ATMEL_TCB_TIMER=y CONFIG_USB=y CONFIG_USB_EHCI_HCD=y CONFIG_USB_STORAGE=y diff --git a/configs/sama5d2_xplained_qspiflash_defconfig b/configs/sama5d2_xplained_qspiflash_defconfig index a6e002e59e..c30a90a3e1 100644 --- a/configs/sama5d2_xplained_qspiflash_defconfig +++ b/configs/sama5d2_xplained_qspiflash_defconfig @@ -91,7 +91,7 @@ CONFIG_DM_SPI=y CONFIG_ATMEL_QSPI=y CONFIG_TIMER=y CONFIG_SPL_TIMER=y -CONFIG_ATMEL_PIT_TIMER=y +CONFIG_ATMEL_TCB_TIMER=y CONFIG_USB=y CONFIG_USB_EHCI_HCD=y CONFIG_USB_STORAGE=y diff --git a/configs/sama5d2_xplained_spiflash_defconfig b/configs/sama5d2_xplained_spiflash_defconfig index 676385fe55..eae54469f8 100644 --- a/configs/sama5d2_xplained_spiflash_defconfig +++ b/configs/sama5d2_xplained_spiflash_defconfig @@ -95,7 +95,7 @@ CONFIG_DM_SPI=y CONFIG_ATMEL_QSPI=y CONFIG_TIMER=y CONFIG_SPL_TIMER=y -CONFIG_ATMEL_PIT_TIMER=y +CONFIG_ATMEL_TCB_TIMER=y CONFIG_USB=y CONFIG_USB_EHCI_HCD=y CONFIG_USB_STORAGE=y

On 3/31/22 11:55 AM, Clément Léger wrote:
When booting under OP-TEE, the SYSC is secured which means the PIT is also not accessible by non-secure world. The TCB 0 however is always available for non-secure world and thus can be used. This series add a TCB driver and enables it in sama5d2 configs.
Applied to u-boot-at91/next , thanks !
participants (2)
-
Clément Léger
-
Eugen.Hristev@microchip.com