* [patch v24 3/4] Documentation: jtag: Add bindings for Aspeed SoC 24xx and 25xx families JTAG master driver
From: Oleksandr Shamray @ 2018-05-29 12:58 UTC (permalink / raw)
To: linux-arm-kernel
In-Reply-To: <1527598720-21220-1-git-send-email-oleksandrs@mellanox.com>
It has been tested on Mellanox system with BMC equipped with
Aspeed 2520 SoC for programming CPLD devices.
Signed-off-by: Oleksandr Shamray <oleksandrs@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Rob Herring <robh@kernel.org>
---
v21->v22
v20->v21
v19->v20
v18->v19
v17->v18
v16->v17
v15->v16
Comments pointed by Joel Stanley <joel.stan@gmail.com>
- change clocks = <&clk_apb> to proper clocks = <&syscon ASPEED_CLK_APB>
- add reset descriptions in bndings file
v14->v15
v13->v14
v12->v13
v11->v12
v10->v11
v9->v10
v8->v9
v7->v8
Comments pointed by pointed by Joel Stanley <joel.stan@gmail.com>
- Change compatible string to ast2400 and ast2000
V6->v7
Comments pointed by Tobias Klauser <tklauser@distanz.ch>
- Fix spell "Doccumentation" -> "Documentation"
v5->v6
Comments pointed by Tobias Klauser <tklauser@distanz.ch>
- Small nit: s/documentation/Documentation/
v4->v5
V3->v4
Comments pointed by Rob Herring <robh@kernel.org>
- delete unnecessary "status" and "reg-shift" descriptions in
bndings file
v2->v3
Comments pointed by Rob Herring <robh@kernel.org>
- split Aspeed jtag driver and binding to sepatrate patches
- delete unnecessary "status" and "reg-shift" descriptions in
bndings file
---
.../devicetree/bindings/jtag/aspeed-jtag.txt | 22 ++++++++++++++++++++
MAINTAINERS | 1 +
2 files changed, 23 insertions(+), 0 deletions(-)
create mode 100644 Documentation/devicetree/bindings/jtag/aspeed-jtag.txt
diff --git a/Documentation/devicetree/bindings/jtag/aspeed-jtag.txt b/Documentation/devicetree/bindings/jtag/aspeed-jtag.txt
new file mode 100644
index 0000000..7c36eb6
--- /dev/null
+++ b/Documentation/devicetree/bindings/jtag/aspeed-jtag.txt
@@ -0,0 +1,22 @@
+Aspeed JTAG driver for ast2400 and ast2500 SoC
+
+Required properties:
+- compatible: Should be one of
+ - "aspeed,ast2400-jtag"
+ - "aspeed,ast2500-jtag"
+- reg contains the offset and length of the JTAG memory
+ region
+- clocks root clock of bus, should reference the APB
+ clock in the second cell
+- resets phandle to reset controller with the reset number in
+ the second cell
+- interrupts should contain JTAG controller interrupt
+
+Example:
+jtag: jtag at 1e6e4000 {
+ compatible = "aspeed,ast2500-jtag";
+ reg = <0x1e6e4000 0x1c>;
+ clocks = <&syscon ASPEED_CLK_APB>;
+ resets = <&syscon ASPEED_RESET_JTAG_MASTER>;
+ interrupts = <43>;
+};
diff --git a/MAINTAINERS b/MAINTAINERS
index e7b8b2c..a5e5f75 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7617,6 +7617,7 @@ S: Maintained
F: include/linux/jtag.h
F: include/uapi/linux/jtag.h
F: drivers/jtag/
+F: Documentation/devicetree/bindings/jtag/
K10TEMP HARDWARE MONITORING DRIVER
M: Clemens Ladisch <clemens@ladisch.de>
--
1.7.1
^ permalink raw reply related
* [patch v24 2/4] drivers: jtag: Add Aspeed SoC 24xx and 25xx families JTAG master driver
From: Oleksandr Shamray @ 2018-05-29 12:58 UTC (permalink / raw)
To: linux-arm-kernel
In-Reply-To: <1527598720-21220-1-git-send-email-oleksandrs@mellanox.com>
Driver adds support of Aspeed 2500/2400 series SOC JTAG master controller.
Driver implements the following jtag ops:
- freq_get;
- freq_set;
- status_get;
- idle;
- xfer;
It has been tested on Mellanox system with BMC equipped with
Aspeed 2520 SoC for programming CPLD devices.
Signed-off-by: Oleksandr Shamray <oleksandrs@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Philippe Ombredanne <pombredanne@nexb.com>
Acked-by: Joel Stanley <joel@jms.id.au>
---
v21->v22
Comments pointed by Andy Shevchenko <andy.shevchenko@gmail.com>
- rearrange ASPEED register defines
- simplified JTAG divider calculation formula
- change delay function in bit-bang operation
- add helper functions for TAP states switching
- remove unnecessary comments
- remove redundant debug messages
- make dines for repetative register bit sets
- fixed indentation
- change checks from negative to positive
- add error check for clk_prepare_enable
- rework driver alloc/register to devm_ variant
- Increasing line length up to 85 in order to improve readability
v20->v21
v19->v20
Notifications from kbuild test robot <lkp@intel.com>
- add static declaration to 'aspeed_jtag_init' and
'aspeed_jtag_deinit' functions
v18->v19
v17->v18
v16->v17
v15->v16
Comments pointed by Joel Stanley <joel.stan@gmail.com>
- Add reset_control on Jtag init/deinit
v14->v15
Comments pointed by Joel Stanley <joel.stan@gmail.com>
- Add ARCH_ASPEED || COMPILE_TEST to Kconfig
- remove unused offset variable
- remove "aspeed_jtag" from dev_err and dev_dbg messages
- change clk_prepare_enable initialisation order
v13->v14
Comments pointed by Philippe Ombredanne <pombredanne@nexb.com>
- Change style of head block comment from /**/ to //
v12->v13
Comments pointed by Philippe Ombredanne <pombredanne@nexb.com>
- Change jtag-aspeed.c licence type to
SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note
and reorder line with license- add reset descriptions in bndings file
in description
Comments pointed by Kun Yi <kunyi@google.com>
- Changed capability check for aspeed,ast2400-jtag/ast200-jtag
v11->v12
Comments pointed by Chip Bilbrey <chip@bilbrey.org>
- Remove access mode from xfer and idle transactions
- Add new ioctl JTAG_SIOCMODE for set hw mode
v10->v11
v9->v10
V8->v9
Comments pointed by Arnd Bergmann <arnd@arndb.de>
- add *data parameter to xfer function prototype
v7->v8
Comments pointed by Joel Stanley <joel.stan@gmail.com>
- aspeed_jtag_init replace goto to return;
- change input variables type from __u32 to u32
in functios freq_get, freq_set, status_get
- change sm_ variables type from char to u8
- in jatg_init add disable clocks on error case
- remove release_mem_region on error case
- remove devm_free_irq on jtag_deinit
- Fix misspelling Disabe/Disable
- Change compatible string to ast2400 and ast2000
v6->v7
Notifications from kbuild test robot <lkp@intel.com>
- Add include <linux/types.h> to jtag-asapeed.c
v5->v6
v4->v5
Comments pointed by Arnd Bergmann <arnd@arndb.de>
- Added HAS_IOMEM dependence in Kconfig to avoid
"undefined reference to `devm_ioremap_resource'" error,
because in some arch this not supported
v3->v4
Comments pointed by Arnd Bergmann <arnd@arndb.de>
- change transaction pointer tdio type to __u64
- change internal status type from enum to __u32
v2->v3
v1->v2
Comments pointed by Greg KH <gregkh@linuxfoundation.org>
- change license type from GPLv2/BSD to GPLv2
Comments pointed by Neil Armstrong <narmstrong@baylibre.com>
- Add clk_prepare_enable/clk_disable_unprepare in clock init/deinit
- Change .compatible to soc-specific compatible names
aspeed,aspeed4000-jtag/aspeed5000-jtag
- Added dt-bindings
Comments pointed by Arnd Bergmann <arnd@arndb.de>
- Reorder functions and removed the forward declarations
- Add static const qualifier to state machine states transitions
- Change .compatible to soc-specific compatible names
aspeed,aspeed4000-jtag/aspeed5000-jtag
- Add dt-bindings
Comments pointed by Randy Dunlap <rdunlap@infradead.org>
- Change module name jtag-aspeed in description in Kconfig
Comments pointed by kbuild test robot <lkp@intel.com>
- Remove invalid include <asm/mach-types.h>
- add resource_size instead of calculation
---
drivers/jtag/Kconfig | 14 +
drivers/jtag/Makefile | 1 +
drivers/jtag/jtag-aspeed.c | 769 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 784 insertions(+), 0 deletions(-)
create mode 100644 drivers/jtag/jtag-aspeed.c
diff --git a/drivers/jtag/Kconfig b/drivers/jtag/Kconfig
index 47771fc..0cc163f 100644
--- a/drivers/jtag/Kconfig
+++ b/drivers/jtag/Kconfig
@@ -15,3 +15,17 @@ menuconfig JTAG
To compile this driver as a module, choose M here: the module will
be called jtag.
+
+menuconfig JTAG_ASPEED
+ tristate "Aspeed SoC JTAG controller support"
+ depends on JTAG && HAS_IOMEM
+ depends on ARCH_ASPEED || COMPILE_TEST
+ help
+ This provides a support for Aspeed JTAG device, equipped on
+ Aspeed SoC 24xx and 25xx families. Drivers allows programming
+ of hardware devices, connected to SoC through the JTAG interface.
+
+ If you want this support, you should say Y here.
+
+ To compile this driver as a module, choose M here: the module will
+ be called jtag-aspeed.
diff --git a/drivers/jtag/Makefile b/drivers/jtag/Makefile
index af37493..04a855e 100644
--- a/drivers/jtag/Makefile
+++ b/drivers/jtag/Makefile
@@ -1 +1,2 @@
obj-$(CONFIG_JTAG) += jtag.o
+obj-$(CONFIG_JTAG_ASPEED) += jtag-aspeed.o
diff --git a/drivers/jtag/jtag-aspeed.c b/drivers/jtag/jtag-aspeed.c
new file mode 100644
index 0000000..b3559f8
--- /dev/null
+++ b/drivers/jtag/jtag-aspeed.c
@@ -0,0 +1,769 @@
+// SPDX-License-Identifier: GPL-2.0
+// drivers/jtag/aspeed-jtag.c
+//
+// Copyright (c) 2018 Mellanox Technologies. All rights reserved.
+// Copyright (c) 2018 Oleksandr Shamray <oleksandrs@mellanox.com>
+
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/jtag.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/delay.h>
+#include <uapi/linux/jtag.h>
+
+#define ASPEED_JTAG_DATA 0x00
+#define ASPEED_JTAG_INST 0x04
+#define ASPEED_JTAG_CTRL 0x08
+#define ASPEED_JTAG_ISR 0x0C
+#define ASPEED_JTAG_SW 0x10
+#define ASPEED_JTAG_TCK 0x14
+#define ASPEED_JTAG_EC 0x18
+
+#define ASPEED_JTAG_DATA_MSB 0x01
+#define ASPEED_JTAG_DATA_CHUNK_SIZE 0x20
+
+/* ASPEED_JTAG_CTRL: Engine Control */
+#define ASPEED_JTAG_CTL_ENG_EN BIT(31)
+#define ASPEED_JTAG_CTL_ENG_OUT_EN BIT(30)
+#define ASPEED_JTAG_CTL_FORCE_TMS BIT(29)
+#define ASPEED_JTAG_CTL_INST_LEN(x) ((x) << 20)
+#define ASPEED_JTAG_CTL_LASPEED_INST BIT(17)
+#define ASPEED_JTAG_CTL_INST_EN BIT(16)
+#define ASPEED_JTAG_CTL_DR_UPDATE BIT(10)
+#define ASPEED_JTAG_CTL_DATA_LEN(x) ((x) << 4)
+#define ASPEED_JTAG_CTL_LASPEED_DATA BIT(1)
+#define ASPEED_JTAG_CTL_DATA_EN BIT(0)
+
+/* ASPEED_JTAG_ISR : Interrupt status and enable */
+#define ASPEED_JTAG_ISR_INST_PAUSE BIT(19)
+#define ASPEED_JTAG_ISR_INST_COMPLETE BIT(18)
+#define ASPEED_JTAG_ISR_DATA_PAUSE BIT(17)
+#define ASPEED_JTAG_ISR_DATA_COMPLETE BIT(16)
+#define ASPEED_JTAG_ISR_INST_PAUSE_EN BIT(3)
+#define ASPEED_JTAG_ISR_INST_COMPLETE_EN BIT(2)
+#define ASPEED_JTAG_ISR_DATA_PAUSE_EN BIT(1)
+#define ASPEED_JTAG_ISR_DATA_COMPLETE_EN BIT(0)
+#define ASPEED_JTAG_ISR_INT_EN_MASK GENMASK(3, 0)
+#define ASPEED_JTAG_ISR_INT_MASK GENMASK(19, 16)
+
+/* ASPEED_JTAG_SW : Software Mode and Status */
+#define ASPEED_JTAG_SW_MODE_EN BIT(19)
+#define ASPEED_JTAG_SW_MODE_TCK BIT(18)
+#define ASPEED_JTAG_SW_MODE_TMS BIT(17)
+#define ASPEED_JTAG_SW_MODE_TDIO BIT(16)
+
+/* ASPEED_JTAG_TCK : TCK Control */
+#define ASPEED_JTAG_TCK_DIVISOR_MASK GENMASK(10, 0)
+#define ASPEED_JTAG_TCK_GET_DIV(x) ((x) & ASPEED_JTAG_TCK_DIVISOR_MASK)
+
+/* ASPEED_JTAG_EC : Controller set for go to IDLE */
+#define ASPEED_JTAG_EC_GO_IDLE BIT(0)
+
+#define ASPEED_JTAG_IOUT_LEN(len) \
+ (ASPEED_JTAG_CTL_ENG_EN | \
+ ASPEED_JTAG_CTL_ENG_OUT_EN | \
+ ASPEED_JTAG_CTL_INST_LEN(len))
+
+#define ASPEED_JTAG_DOUT_LEN(len) \
+ (ASPEED_JTAG_CTL_ENG_EN | \
+ ASPEED_JTAG_CTL_ENG_OUT_EN | \
+ ASPEED_JTAG_CTL_DATA_LEN(len))
+
+#define ASPEED_JTAG_SW_TDIO (ASPEED_JTAG_SW_MODE_EN | ASPEED_JTAG_SW_MODE_TDIO)
+
+#define ASPEED_JTAG_GET_TDI(direction, byte) \
+ ((direction == JTAG_READ_XFER) ? UINT_MAX : byte)
+
+#define ASPEED_JTAG_TCK_WAIT 10
+#define ASPEED_JTAG_RESET_CNTR 10
+
+#define ASPEED_JTAG_NAME "jtag-aspeed"
+
+struct aspeed_jtag {
+ void __iomem *reg_base;
+ struct device *dev;
+ struct clk *pclk;
+ enum jtag_endstate status;
+ int irq;
+ struct reset_control *rst;
+ u32 flag;
+ wait_queue_head_t jtag_wq;
+ u32 mode;
+};
+
+static char *end_status_str[] = {"idle", "ir pause", "drpause"};
+
+static u32 aspeed_jtag_read(struct aspeed_jtag *aspeed_jtag, u32 reg)
+{
+ return readl(aspeed_jtag->reg_base + reg);
+}
+
+static void
+aspeed_jtag_write(struct aspeed_jtag *aspeed_jtag, u32 val, u32 reg)
+{
+ writel(val, aspeed_jtag->reg_base + reg);
+}
+
+static int aspeed_jtag_freq_set(struct jtag *jtag, u32 freq)
+{
+ struct aspeed_jtag *aspeed_jtag = jtag_priv(jtag);
+ unsigned long apb_frq;
+ u32 tck_val;
+ u16 div;
+
+ apb_frq = clk_get_rate(aspeed_jtag->pclk);
+ if (!apb_frq)
+ return -ENOTSUPP;
+
+ div = (apb_frq - 1) / freq;
+ tck_val = aspeed_jtag_read(aspeed_jtag, ASPEED_JTAG_TCK);
+ aspeed_jtag_write(aspeed_jtag,
+ (tck_val & ASPEED_JTAG_TCK_DIVISOR_MASK) | div,
+ ASPEED_JTAG_TCK);
+ return 0;
+}
+
+static int aspeed_jtag_freq_get(struct jtag *jtag, u32 *frq)
+{
+ struct aspeed_jtag *aspeed_jtag = jtag_priv(jtag);
+ u32 pclk;
+ u32 tck;
+
+ pclk = clk_get_rate(aspeed_jtag->pclk);
+ tck = aspeed_jtag_read(aspeed_jtag, ASPEED_JTAG_TCK);
+ *frq = pclk / (ASPEED_JTAG_TCK_GET_DIV(tck) + 1);
+
+ return 0;
+}
+
+static int aspeed_jtag_mode_set(struct jtag *jtag, u32 mode)
+{
+ struct aspeed_jtag *aspeed_jtag = jtag_priv(jtag);
+
+ aspeed_jtag->mode = mode;
+ return 0;
+}
+
+static void aspeed_jtag_sw_delay(struct aspeed_jtag *aspeed_jtag, int cnt)
+{
+ int i;
+
+ for (i = 0; i < cnt; i++)
+ aspeed_jtag_read(aspeed_jtag, ASPEED_JTAG_SW);
+}
+
+static char aspeed_jtag_tck_cycle(struct aspeed_jtag *aspeed_jtag,
+ u8 tms, u8 tdi)
+{
+ char tdo = 0;
+
+ /* TCK = 0 */
+ aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_SW_MODE_EN |
+ (tms * ASPEED_JTAG_SW_MODE_TMS) |
+ (tdi * ASPEED_JTAG_SW_MODE_TDIO), ASPEED_JTAG_SW);
+
+ ndelay(ASPEED_JTAG_TCK_WAIT);
+ aspeed_jtag_sw_delay(aspeed_jtag, ASPEED_JTAG_TCK_WAIT);
+
+ /* TCK = 1 */
+ aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_SW_MODE_EN |
+ ASPEED_JTAG_SW_MODE_TCK |
+ (tms * ASPEED_JTAG_SW_MODE_TMS) |
+ (tdi * ASPEED_JTAG_SW_MODE_TDIO), ASPEED_JTAG_SW);
+
+ if (aspeed_jtag_read(aspeed_jtag, ASPEED_JTAG_SW) &
+ ASPEED_JTAG_SW_MODE_TDIO)
+ tdo = 1;
+
+ aspeed_jtag_sw_delay(aspeed_jtag, ASPEED_JTAG_TCK_WAIT);
+
+ /* TCK = 0 */
+ aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_SW_MODE_EN |
+ (tms * ASPEED_JTAG_SW_MODE_TMS) |
+ (tdi * ASPEED_JTAG_SW_MODE_TDIO), ASPEED_JTAG_SW);
+ return tdo;
+}
+
+static void aspeed_jtag_wait_instruction_pause(struct aspeed_jtag *aspeed_jtag)
+{
+ wait_event_interruptible(aspeed_jtag->jtag_wq,
+ aspeed_jtag->flag & ASPEED_JTAG_ISR_INST_PAUSE);
+ aspeed_jtag->flag &= ~ASPEED_JTAG_ISR_INST_PAUSE;
+}
+
+static void
+aspeed_jtag_wait_instruction_complete(struct aspeed_jtag *aspeed_jtag)
+{
+ wait_event_interruptible(aspeed_jtag->jtag_wq,
+ aspeed_jtag->flag & ASPEED_JTAG_ISR_INST_COMPLETE);
+ aspeed_jtag->flag &= ~ASPEED_JTAG_ISR_INST_COMPLETE;
+}
+
+static void
+aspeed_jtag_wait_data_pause_complete(struct aspeed_jtag *aspeed_jtag)
+{
+ wait_event_interruptible(aspeed_jtag->jtag_wq,
+ aspeed_jtag->flag & ASPEED_JTAG_ISR_DATA_PAUSE);
+ aspeed_jtag->flag &= ~ASPEED_JTAG_ISR_DATA_PAUSE;
+}
+
+static void aspeed_jtag_wait_data_complete(struct aspeed_jtag *aspeed_jtag)
+{
+ wait_event_interruptible(aspeed_jtag->jtag_wq,
+ aspeed_jtag->flag & ASPEED_JTAG_ISR_DATA_COMPLETE);
+ aspeed_jtag->flag &= ~ASPEED_JTAG_ISR_DATA_COMPLETE;
+}
+
+static void aspeed_jtag_sm_cycle(struct aspeed_jtag *aspeed_jtag,
+ const u8 *tms, int len)
+{
+ int i;
+
+ for (i = 0; i < len; i++)
+ aspeed_jtag_tck_cycle(aspeed_jtag, tms[i], 0);
+}
+
+static void aspeed_jtag_run_idle(struct aspeed_jtag *aspeed_jtag,
+ struct jtag_run_test_idle *runtest)
+{
+ static const u8 sm_idle_irpause[] = {1, 1, 0, 1, 0};
+ static const u8 sm_idle_drpause[] = {1, 0, 1, 0};
+
+ switch (runtest->endstate) {
+ case JTAG_STATE_PAUSEIR:
+ /* ->DRSCan->IRSCan->IRCap->IRExit1->PauseIR */
+ aspeed_jtag_sm_cycle(aspeed_jtag, sm_idle_irpause,
+ sizeof(sm_idle_irpause));
+ aspeed_jtag->status = JTAG_STATE_PAUSEIR;
+ break;
+ case JTAG_STATE_PAUSEDR:
+ /* ->DRSCan->DRCap->DRExit1->PauseDR */
+ aspeed_jtag_sm_cycle(aspeed_jtag, sm_idle_drpause,
+ sizeof(sm_idle_drpause));
+
+ aspeed_jtag->status = JTAG_STATE_PAUSEDR;
+ break;
+ case JTAG_STATE_IDLE:
+ /* IDLE */
+ aspeed_jtag_tck_cycle(aspeed_jtag, 0, 0);
+ aspeed_jtag->status = JTAG_STATE_IDLE;
+ break;
+ default:
+ break;
+ }
+}
+
+static void aspeed_jtag_run_pause(struct aspeed_jtag *aspeed_jtag,
+ struct jtag_run_test_idle *runtest)
+{
+ static const u8 sm_pause_irpause[] = {1, 1, 1, 1, 0, 1, 0};
+ static const u8 sm_pause_drpause[] = {1, 1, 1, 0, 1, 0};
+ static const u8 sm_pause_idle[] = {1, 1, 0};
+
+ /* From IR/DR Pa.use */
+ switch (runtest->endstate) {
+ case JTAG_STATE_PAUSEIR:
+ /*
+ * to Exit2 IR/DR->Updt IR/DR->DRSCan->IRSCan->IRCap->
+ * IRExit1->PauseIR
+ */
+ aspeed_jtag_sm_cycle(aspeed_jtag, sm_pause_irpause,
+ sizeof(sm_pause_irpause));
+
+ aspeed_jtag->status = JTAG_STATE_PAUSEIR;
+ break;
+ case JTAG_STATE_PAUSEDR:
+ /*
+ * to Exit2 IR/DR->Updt IR/DR->DRSCan->DRCap->
+ * DRExit1->PauseDR
+ */
+ aspeed_jtag_sm_cycle(aspeed_jtag, sm_pause_drpause,
+ sizeof(sm_pause_drpause));
+ aspeed_jtag->status = JTAG_STATE_PAUSEDR;
+ break;
+ case JTAG_STATE_IDLE:
+ /* to Exit2 IR/DR->Updt IR/DR->IDLE */
+ aspeed_jtag_sm_cycle(aspeed_jtag, sm_pause_idle,
+ sizeof(sm_pause_idle));
+ aspeed_jtag->status = JTAG_STATE_IDLE;
+ break;
+ default:
+ break;
+ }
+}
+
+static void aspeed_jtag_run_test_idle_sw(struct aspeed_jtag *aspeed_jtag,
+ struct jtag_run_test_idle *runtest)
+{
+ int i;
+
+ /* SW mode from idle/pause-> to pause/idle */
+ if (runtest->reset) {
+ for (i = 0; i < ASPEED_JTAG_RESET_CNTR; i++)
+ aspeed_jtag_tck_cycle(aspeed_jtag, 1, 0);
+ }
+
+ switch (aspeed_jtag->status) {
+ case JTAG_STATE_IDLE:
+ aspeed_jtag_run_idle(aspeed_jtag, runtest);
+ break;
+
+ case JTAG_STATE_PAUSEIR:
+ /* Fall-through */
+ case JTAG_STATE_PAUSEDR:
+ aspeed_jtag_run_pause(aspeed_jtag, runtest);
+ break;
+
+ default:
+ dev_err(aspeed_jtag->dev, "aspeed_jtag_run_test_idle error\n");
+ break;
+ }
+
+ /* Stay on IDLE for at least TCK cycle */
+ for (i = 0; i < runtest->tck; i++)
+ aspeed_jtag_tck_cycle(aspeed_jtag, 0, 0);
+}
+
+static int aspeed_jtag_idle(struct jtag *jtag,
+ struct jtag_run_test_idle *runtest)
+{
+ struct aspeed_jtag *aspeed_jtag = jtag_priv(jtag);
+
+ dev_dbg(aspeed_jtag->dev, "runtest, status:%d, mode:%s, state:%s, reset:%d, tck:%d\n",
+ aspeed_jtag->status,
+ aspeed_jtag->mode & JTAG_XFER_HW_MODE ? "HW" : "SW",
+ end_status_str[runtest->endstate], runtest->reset,
+ runtest->tck);
+
+ if (!(aspeed_jtag->mode & JTAG_XFER_HW_MODE)) {
+ aspeed_jtag_run_test_idle_sw(aspeed_jtag, runtest);
+ return 0;
+ }
+
+ /* Disable sw mode */
+ aspeed_jtag_write(aspeed_jtag, 0, ASPEED_JTAG_SW);
+ /* x TMS high + 1 TMS low */
+ if (runtest->reset)
+ aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_CTL_ENG_EN |
+ ASPEED_JTAG_CTL_ENG_OUT_EN |
+ ASPEED_JTAG_CTL_FORCE_TMS, ASPEED_JTAG_CTRL);
+ else
+ aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_EC_GO_IDLE,
+ ASPEED_JTAG_EC);
+
+ aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_SW_TDIO, ASPEED_JTAG_SW);
+
+ aspeed_jtag->status = JTAG_STATE_IDLE;
+ return 0;
+}
+
+static void aspeed_jtag_xfer_sw(struct aspeed_jtag *aspeed_jtag,
+ struct jtag_xfer *xfer, u32 *data)
+{
+ static const u8 sm_update_shiftir[] = { 1, 1, 0, 0 };
+ static const u8 sm_update_shiftdr[] = { 1, 0, 0 };
+ static const u8 sm_pause_idle[] = { 1, 1, 0 };
+ static const u8 sm_pause_update[] = { 1, 1 };
+ unsigned long remain_xfer = xfer->length;
+ unsigned long shift_bits = 0;
+ unsigned long index = 0;
+ unsigned long tdi;
+ char tdo;
+
+ if (aspeed_jtag->status != JTAG_STATE_IDLE) {
+ /*IR/DR Pause->Exit2 IR / DR->Update IR /DR */
+ aspeed_jtag_sm_cycle(aspeed_jtag, sm_pause_update,
+ sizeof(sm_pause_update));
+ }
+
+ if (xfer->type == JTAG_SIR_XFER)
+ /* ->IRSCan->CapIR->ShiftIR */
+ aspeed_jtag_sm_cycle(aspeed_jtag, sm_update_shiftir,
+ sizeof(sm_update_shiftir));
+ else
+ /* ->DRScan->DRCap->DRShift */
+ aspeed_jtag_sm_cycle(aspeed_jtag, sm_update_shiftdr,
+ sizeof(sm_update_shiftdr));
+
+ tdi = ASPEED_JTAG_GET_TDI(xfer->direction, data[index]);
+
+ while (remain_xfer > 1) {
+ tdo = aspeed_jtag_tck_cycle(aspeed_jtag, 0,
+ tdi & ASPEED_JTAG_DATA_MSB);
+ data[index] |= tdo << (shift_bits %
+ ASPEED_JTAG_DATA_CHUNK_SIZE);
+
+ tdi >>= 1;
+ shift_bits++;
+ remain_xfer--;
+
+ if (shift_bits % ASPEED_JTAG_DATA_CHUNK_SIZE == 0) {
+ tdo = 0;
+ index++;
+
+ tdi = ASPEED_JTAG_GET_TDI(xfer->direction, data[index]);
+ }
+ }
+
+ tdo = aspeed_jtag_tck_cycle(aspeed_jtag, 1, tdi & ASPEED_JTAG_DATA_MSB);
+ data[index] |= tdo << (shift_bits % ASPEED_JTAG_DATA_CHUNK_SIZE);
+
+ /* DIPause/DRPause */
+ aspeed_jtag_tck_cycle(aspeed_jtag, 0, 0);
+
+ if (xfer->endstate == JTAG_STATE_IDLE) {
+ /* ->DRExit2->DRUpdate->IDLE */
+ aspeed_jtag_sm_cycle(aspeed_jtag, sm_pause_idle,
+ sizeof(sm_pause_idle));
+ }
+}
+
+static void aspeed_jtag_xfer_push_data(struct aspeed_jtag *aspeed_jtag,
+ enum jtag_xfer_type type, u32 bits_len)
+{
+ if (type == JTAG_SIR_XFER) {
+ aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_IOUT_LEN(bits_len),
+ ASPEED_JTAG_CTRL);
+ aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_DOUT_LEN(bits_len) |
+ ASPEED_JTAG_CTL_INST_EN, ASPEED_JTAG_CTRL);
+ } else {
+ aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_DOUT_LEN(bits_len),
+ ASPEED_JTAG_CTRL);
+ aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_DOUT_LEN(bits_len) |
+ ASPEED_JTAG_CTL_DATA_EN, ASPEED_JTAG_CTRL);
+ }
+}
+
+static void aspeed_jtag_xfer_push_data_last(struct aspeed_jtag *aspeed_jtag,
+ enum jtag_xfer_type type,
+ u32 shift_bits,
+ enum jtag_endstate endstate)
+{
+ if (endstate == JTAG_STATE_IDLE) {
+ if (type == JTAG_SIR_XFER) {
+ dev_dbg(aspeed_jtag->dev, "IR Keep Pause\n");
+
+ aspeed_jtag_write(aspeed_jtag,
+ ASPEED_JTAG_IOUT_LEN(shift_bits),
+ ASPEED_JTAG_CTRL);
+ aspeed_jtag_write(aspeed_jtag,
+ ASPEED_JTAG_IOUT_LEN(shift_bits) |
+ ASPEED_JTAG_CTL_INST_EN,
+ ASPEED_JTAG_CTRL);
+ aspeed_jtag_wait_instruction_pause(aspeed_jtag);
+ } else {
+ dev_dbg(aspeed_jtag->dev, "DR Keep Pause\n");
+ aspeed_jtag_write(aspeed_jtag,
+ ASPEED_JTAG_DOUT_LEN(shift_bits) |
+ ASPEED_JTAG_CTL_DR_UPDATE,
+ ASPEED_JTAG_CTRL);
+ aspeed_jtag_write(aspeed_jtag,
+ ASPEED_JTAG_DOUT_LEN(shift_bits) |
+ ASPEED_JTAG_CTL_DR_UPDATE |
+ ASPEED_JTAG_CTL_DATA_EN,
+ ASPEED_JTAG_CTRL);
+ aspeed_jtag_wait_data_pause_complete(aspeed_jtag);
+ }
+ } else {
+ if (type == JTAG_SIR_XFER) {
+ dev_dbg(aspeed_jtag->dev, "IR go IDLE\n");
+
+ aspeed_jtag_write(aspeed_jtag,
+ ASPEED_JTAG_IOUT_LEN(shift_bits) |
+ ASPEED_JTAG_CTL_LASPEED_INST,
+ ASPEED_JTAG_CTRL);
+ aspeed_jtag_write(aspeed_jtag,
+ ASPEED_JTAG_IOUT_LEN(shift_bits) |
+ ASPEED_JTAG_CTL_LASPEED_INST |
+ ASPEED_JTAG_CTL_INST_EN,
+ ASPEED_JTAG_CTRL);
+ aspeed_jtag_wait_instruction_complete(aspeed_jtag);
+ } else {
+ dev_dbg(aspeed_jtag->dev, "DR go IDLE\n");
+
+ aspeed_jtag_write(aspeed_jtag,
+ ASPEED_JTAG_DOUT_LEN(shift_bits) |
+ ASPEED_JTAG_CTL_LASPEED_DATA,
+ ASPEED_JTAG_CTRL);
+ aspeed_jtag_write(aspeed_jtag,
+ ASPEED_JTAG_DOUT_LEN(shift_bits) |
+ ASPEED_JTAG_CTL_LASPEED_DATA |
+ ASPEED_JTAG_CTL_DATA_EN,
+ ASPEED_JTAG_CTRL);
+ aspeed_jtag_wait_data_complete(aspeed_jtag);
+ }
+ }
+}
+
+static void aspeed_jtag_xfer_hw(struct aspeed_jtag *aspeed_jtag,
+ struct jtag_xfer *xfer, u32 *data)
+{
+ unsigned long remain_xfer = xfer->length;
+ unsigned long index = 0;
+ char shift_bits;
+ u32 data_reg;
+
+ data_reg = xfer->type == JTAG_SIR_XFER ?
+ ASPEED_JTAG_INST : ASPEED_JTAG_DATA;
+ while (remain_xfer) {
+ if (xfer->direction == JTAG_WRITE_XFER)
+ aspeed_jtag_write(aspeed_jtag, data[index], data_reg);
+ else
+ aspeed_jtag_write(aspeed_jtag, 0, data_reg);
+
+ if (remain_xfer > ASPEED_JTAG_DATA_CHUNK_SIZE) {
+ shift_bits = ASPEED_JTAG_DATA_CHUNK_SIZE;
+
+ /*
+ * Read bytes were not equals to column length
+ * and go to Pause-DR
+ */
+ aspeed_jtag_xfer_push_data(aspeed_jtag, xfer->type,
+ shift_bits);
+ } else {
+ /*
+ * Read bytes equals to column length =>
+ * Update-DR
+ */
+ shift_bits = remain_xfer;
+ aspeed_jtag_xfer_push_data_last(aspeed_jtag, xfer->type,
+ shift_bits,
+ xfer->endstate);
+ }
+
+ if (xfer->direction == JTAG_READ_XFER) {
+ if (shift_bits < ASPEED_JTAG_DATA_CHUNK_SIZE) {
+ data[index] = aspeed_jtag_read(aspeed_jtag,
+ data_reg);
+
+ data[index] >>= ASPEED_JTAG_DATA_CHUNK_SIZE -
+ shift_bits;
+ } else {
+ data[index] = aspeed_jtag_read(aspeed_jtag,
+ data_reg);
+ }
+ }
+
+ remain_xfer = remain_xfer - shift_bits;
+ index++;
+ }
+}
+
+static int aspeed_jtag_xfer(struct jtag *jtag, struct jtag_xfer *xfer,
+ u8 *xfer_data)
+{
+ struct aspeed_jtag *aspeed_jtag = jtag_priv(jtag);
+
+ dev_dbg(aspeed_jtag->dev, " %s %s xfer, mode:%s, END:%d, len:%d\n",
+ xfer->type == JTAG_SIR_XFER ? "SIR" : "SDR",
+ xfer->direction == JTAG_READ_XFER ? "READ" : "WRITE",
+ aspeed_jtag->mode & JTAG_XFER_HW_MODE ? "HW" : "SW",
+ xfer->endstate, xfer->length);
+
+ if (!(aspeed_jtag->mode & JTAG_XFER_HW_MODE)) {
+ /* SW mode */
+ aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_SW_TDIO, ASPEED_JTAG_SW);
+
+ aspeed_jtag_xfer_sw(aspeed_jtag, xfer, (u32 *)xfer_data);
+ } else {
+ /* HW mode */
+ aspeed_jtag_write(aspeed_jtag, 0, ASPEED_JTAG_SW);
+ aspeed_jtag_xfer_hw(aspeed_jtag, xfer, (u32 *)xfer_data);
+ }
+
+ aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_SW_TDIO, ASPEED_JTAG_SW);
+ aspeed_jtag->status = xfer->endstate;
+ return 0;
+}
+
+static int aspeed_jtag_status_get(struct jtag *jtag, u32 *status)
+{
+ struct aspeed_jtag *aspeed_jtag = jtag_priv(jtag);
+
+ *status = aspeed_jtag->status;
+ return 0;
+}
+
+static irqreturn_t aspeed_jtag_interrupt(s32 this_irq, void *dev_id)
+{
+ struct aspeed_jtag *aspeed_jtag = dev_id;
+ irqreturn_t ret;
+ u32 status;
+
+ status = aspeed_jtag_read(aspeed_jtag, ASPEED_JTAG_ISR);
+
+ if (status & ASPEED_JTAG_ISR_INT_MASK) {
+ aspeed_jtag_write(aspeed_jtag,
+ (status & ASPEED_JTAG_ISR_INT_MASK)
+ | (status & ASPEED_JTAG_ISR_INT_EN_MASK),
+ ASPEED_JTAG_ISR);
+ aspeed_jtag->flag |= status & ASPEED_JTAG_ISR_INT_MASK;
+ }
+
+ if (aspeed_jtag->flag) {
+ wake_up_interruptible(&aspeed_jtag->jtag_wq);
+ ret = IRQ_HANDLED;
+ } else {
+ dev_err(aspeed_jtag->dev, "irq status:%x\n",
+ status);
+ ret = IRQ_NONE;
+ }
+ return ret;
+}
+
+static int aspeed_jtag_init(struct platform_device *pdev,
+ struct aspeed_jtag *aspeed_jtag)
+{
+ struct resource *res;
+ int err;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ aspeed_jtag->reg_base = devm_ioremap_resource(aspeed_jtag->dev, res);
+ if (IS_ERR(aspeed_jtag->reg_base))
+ return -ENOMEM;
+
+ aspeed_jtag->pclk = devm_clk_get(aspeed_jtag->dev, NULL);
+ if (IS_ERR(aspeed_jtag->pclk)) {
+ dev_err(aspeed_jtag->dev, "devm_clk_get failed\n");
+ return PTR_ERR(aspeed_jtag->pclk);
+ }
+
+ aspeed_jtag->irq = platform_get_irq(pdev, 0);
+ if (aspeed_jtag->irq < 0) {
+ dev_err(aspeed_jtag->dev, "no irq specified\n");
+ return -ENOENT;
+ }
+
+ if (clk_prepare_enable(aspeed_jtag->pclk)) {
+ dev_err(aspeed_jtag->dev, "no irq specified\n");
+ return -ENOENT;
+ }
+
+ aspeed_jtag->rst = devm_reset_control_get_shared(&pdev->dev, NULL);
+ if (IS_ERR(aspeed_jtag->rst)) {
+ dev_err(aspeed_jtag->dev,
+ "missing or invalid reset controller device tree entry");
+ return PTR_ERR(aspeed_jtag->rst);
+ }
+ reset_control_deassert(aspeed_jtag->rst);
+
+ /* Enable clock */
+ aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_CTL_ENG_EN |
+ ASPEED_JTAG_CTL_ENG_OUT_EN, ASPEED_JTAG_CTRL);
+ aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_SW_TDIO, ASPEED_JTAG_SW);
+
+ err = devm_request_irq(aspeed_jtag->dev, aspeed_jtag->irq,
+ aspeed_jtag_interrupt, 0,
+ "aspeed-jtag", aspeed_jtag);
+ if (err) {
+ dev_err(aspeed_jtag->dev, "unable to get IRQ");
+ goto clk_unprep;
+ }
+
+ aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_ISR_INST_PAUSE |
+ ASPEED_JTAG_ISR_INST_COMPLETE |
+ ASPEED_JTAG_ISR_DATA_PAUSE |
+ ASPEED_JTAG_ISR_DATA_COMPLETE |
+ ASPEED_JTAG_ISR_INST_PAUSE_EN |
+ ASPEED_JTAG_ISR_INST_COMPLETE_EN |
+ ASPEED_JTAG_ISR_DATA_PAUSE_EN |
+ ASPEED_JTAG_ISR_DATA_COMPLETE_EN,
+ ASPEED_JTAG_ISR);
+
+ aspeed_jtag->flag = 0;
+ aspeed_jtag->mode = 0;
+ init_waitqueue_head(&aspeed_jtag->jtag_wq);
+ return 0;
+
+clk_unprep:
+ clk_disable_unprepare(aspeed_jtag->pclk);
+ return err;
+}
+
+static int aspeed_jtag_deinit(struct platform_device *pdev,
+ struct aspeed_jtag *aspeed_jtag)
+{
+ aspeed_jtag_write(aspeed_jtag, 0, ASPEED_JTAG_ISR);
+ /* Disable clock */
+ aspeed_jtag_write(aspeed_jtag, 0, ASPEED_JTAG_CTRL);
+ reset_control_assert(aspeed_jtag->rst);
+ clk_disable_unprepare(aspeed_jtag->pclk);
+ return 0;
+}
+
+static const struct jtag_ops aspeed_jtag_ops = {
+ .freq_get = aspeed_jtag_freq_get,
+ .freq_set = aspeed_jtag_freq_set,
+ .status_get = aspeed_jtag_status_get,
+ .idle = aspeed_jtag_idle,
+ .xfer = aspeed_jtag_xfer,
+ .mode_set = aspeed_jtag_mode_set
+};
+
+static int aspeed_jtag_probe(struct platform_device *pdev)
+{
+ struct aspeed_jtag *aspeed_jtag;
+ struct jtag *jtag;
+ int err;
+
+ jtag = jtag_alloc(&pdev->dev, sizeof(*aspeed_jtag), &aspeed_jtag_ops);
+ if (!jtag)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, jtag);
+ aspeed_jtag = jtag_priv(jtag);
+ aspeed_jtag->dev = &pdev->dev;
+
+ /* Initialize device*/
+ err = aspeed_jtag_init(pdev, aspeed_jtag);
+ if (err)
+ goto err_jtag_init;
+
+ /* Initialize JTAG core structure*/
+ err = devm_jtag_register(aspeed_jtag->dev, jtag);
+ if (err)
+ goto err_jtag_register;
+
+ return 0;
+
+err_jtag_register:
+ aspeed_jtag_deinit(pdev, aspeed_jtag);
+err_jtag_init:
+ jtag_free(jtag);
+ return err;
+}
+
+static int aspeed_jtag_remove(struct platform_device *pdev)
+{
+ struct jtag *jtag = platform_get_drvdata(pdev);
+
+ aspeed_jtag_deinit(pdev, jtag_priv(jtag));
+ return 0;
+}
+
+static const struct of_device_id aspeed_jtag_of_match[] = {
+ { .compatible = "aspeed,ast2400-jtag", },
+ { .compatible = "aspeed,ast2500-jtag", },
+ {}
+};
+
+static struct platform_driver aspeed_jtag_driver = {
+ .probe = aspeed_jtag_probe,
+ .remove = aspeed_jtag_remove,
+ .driver = {
+ .name = ASPEED_JTAG_NAME,
+ .of_match_table = aspeed_jtag_of_match,
+ },
+};
+module_platform_driver(aspeed_jtag_driver);
+
+MODULE_AUTHOR("Oleksandr Shamray <oleksandrs@mellanox.com>");
+MODULE_DESCRIPTION("ASPEED JTAG driver");
+MODULE_LICENSE("GPL v2");
--
1.7.1
^ permalink raw reply related
* [patch v24 1/4] drivers: jtag: Add JTAG core driver
From: Oleksandr Shamray @ 2018-05-29 12:58 UTC (permalink / raw)
To: linux-arm-kernel
In-Reply-To: <1527598720-21220-1-git-send-email-oleksandrs@mellanox.com>
Initial patch for JTAG driver
JTAG class driver provide infrastructure to support hardware/software
JTAG platform drivers. It provide user layer API interface for flashing
and debugging external devices which equipped with JTAG interface
using standard transactions.
Driver exposes set of IOCTL to user space for:
- XFER:
- SIR (Scan Instruction Register, IEEE 1149.1 Data Register scan);
- SDR (Scan Data Register, IEEE 1149.1 Instruction Register scan);
- RUNTEST (Forces the IEEE 1149.1 bus to a run state for a specified
number of clocks).
- SIOCFREQ/GIOCFREQ for setting and reading JTAG frequency.
Driver core provides set of internal APIs for allocation and
registration:
- jtag_register;
- jtag_unregister;
- jtag_alloc;
- jtag_free;
Platform driver on registration with jtag-core creates the next
entry in dev folder:
/dev/jtagX
Signed-off-by: Oleksandr Shamray <oleksandrs@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Philippe Ombredanne <pombredanne@nexb.com>
---
v23->v24
Notifications from kbuild test robot <lkp@intel.com>
- Add include types.h header to jtag.h
v22->v23
Comments pointed by Greg KH <gregkh@linuxfoundation.org>
- remove restriction of allocated JTAG devs-
- add validation fo idle values
- remove unnecessary blank line
- change retcode for xfer
- remove unecessary jtag_release callback
- remove unecessary defined fron jtag.h
- align in one line define JTAG_IOCRUNTEST
v21->v22
Comments pointed by Andy Shevchenko <andy.shevchenko@gmail.com>
- Fix 0x0f -> 0x0F in ioctl-number.txt
- Add description to #define MAX_JTAG_NAME_LEN
- Remove unnecessary entry *dev from struct jtag
- Remove redundant parens
- Described mandatory callbacks and removed unnecessary
- Set JTAG_MAX_XFER_DATA_LEN to power of 2
- rework driver alloc/register to devm_ variant
- increasing line length up to 84 in order to improve readability.
Comments pointed by Randy Dunlap <rdunlap@infradead.org>
- fix spell in ABI doccumentation
v20->v21
Comments pointed by Randy Dunlap <rdunlap@infradead.org>
- Fix JTAG dirver help in Kconfig
v19->v20
Comments pointed by Randy Dunlap <rdunlap@infradead.org>
- Fix JTAG dirver help in Kconfig
Notifications from kbuild test robot <lkp@intel.com>
- fix incompatible type casts
v18->v19
Comments pointed by Julia Cartwright <juliac@eso.teric.us>
- Fix memory leak on jtag_alloc exit
v17->v18
Comments pointed by Julia Cartwright <juliac@eso.teric.us>
- Change to return -EOPNOTSUPP in case of error in JTAG_GIOCFREQ
- Add ops callbacks check to jtag_alloc
- Add err check for copy_to_user
- Move the kfree() above the if (err) in JTAG_IOCXFER
- remove unnecessary check for error after put_user
- add padding to struct jtag_xfer
v16->v17
Comments pointed by Julia Cartwright <juliac@eso.teric.us>
- Fix memory allocation on jtag alloc
- Move out unnecessary form lock on jtag open
- Rework jtag register behavior
v15->v16
Comments pointed by Florian Fainelli <f.fainelli@gmail.com>
- move check jtag->ops->* in ioctl before get_user()
- change error type -EINVAL --> -EBUSY on open already opened jtag
- remove unnecessary ARCH_DMA_MINALIGN flag from kzalloc
- remove define ARCH_DMA_MINALIGN
v14->v15
v13->v14
Comments pointed by Philippe Ombredanne <pombredanne@nexb.com>
- Change style of head block comment from /**/ to //
v12->v13
Comments pointed by Philippe Ombredanne <pombredanne@nexb.com>
- Change jtag.c licence type to
SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note
and reorder line with license in description
v11->v12
Comments pointed by Greg KH <gregkh@linuxfoundation.org>
- Change jtag.h licence type to
SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note
and reorder line with license in description
Comments pointed by Chip Bilbrey <chip@bilbrey.org>
- Remove Apeed reference from uapi jtag.h header
- Remove access mode from xfer and idle transactions
- Add new ioctl JTAG_SIOCMODE for set hw mode
- Add single open per device blocking
v10->v11
Notifications from kbuild test robot <lkp@intel.com>
- Add include types.h header to jtag.h
- fix incompatible type of xfer callback
- remove rdundant class defination
- Fix return order in case of xfer error
V9->v10
Comments pointed by Greg KH <gregkh@linuxfoundation.org>
- remove unnecessary alignment for pirv data
- move jtag_copy_to_user and jtag_copy_from_user code just to ioctl
- move int jtag_run_test_idle_op and jtag_xfer_op code
just to ioctl
- change return error codes to more applicable
- add missing error checks
- fix error check order in ioctl
- remove unnecessary blank lines
- add param validation to ioctl
- remove compat_ioctl
- remove only one open per JTAG port blocking.
User will care about this.
- Fix idr memory leak on jtag_exit
- change cdev device type to misc
V8->v9
Comments pointed by Arnd Bergmann <arnd@arndb.de>
- use get_user() instead of __get_user().
- change jtag->open type from int to atomic_t
- remove spinlock on jtg_open
- remove mutex on jtag_register
- add unregister_chrdev_region on jtag_init err
- add unregister_chrdev_region on jtag_exit
- remove unnecessary pointer casts
- add *data parameter to xfer function prototype
v7->v8
Comments pointed by Moritz Fischer <moritz.fischer@ettus.com>
- Fix misspelling s/friver/driver
v6->v7
Notifications from kbuild test robot <lkp@intel.com>
- Remove include asm/types.h from jtag.h
- Add include <linux/types.h> to jtag.c
v5->v6
v4->v5
v3->v4
Comments pointed by Arnd Bergmann <arnd@arndb.de>
- change transaction pointer tdio type to __u64
- change internal status type from enum to __u32
- reorder jtag_xfer members to avoid the implied padding
- add __packed attribute to jtag_xfer and jtag_run_test_idle
v2->v3
Notifications from kbuild test robot <lkp@intel.com>
- Change include path to <linux/types.h> in jtag.h
v1->v2
Comments pointed by Greg KH <gregkh@linuxfoundation.org>
- Change license type from GPLv2/BSD to GPLv2
- Change type of variables which crossed user/kernel to __type
- Remove "default n" from Kconfig
Comments pointed by Andrew Lunn <andrew@lunn.ch>
- Change list_add_tail in jtag_unregister to list_del
Comments pointed by Neil Armstrong <narmstrong@baylibre.com>
- Add SPDX-License-Identifier instead of license text
Comments pointed by Arnd Bergmann <arnd@arndb.de>
- Change __copy_to_user to memdup_user
- Change __put_user to put_user
- Change type of variables to __type for compatible 32 and 64-bit systems
- Add check for maximum xfer data size
- Change lookup data mechanism to get jtag data from inode
- Add .compat_ioctl to file ops
- Add mem alignment for jtag priv data
Comments pointed by Tobias Klauser <tklauser@distanz.ch>
- Change function names to avoid match with variable types
- Fix description for jtag_ru_test_idle in uapi jtag.h
- Fix misprints IDEL/IDLE, trough/through
---
Documentation/ioctl/ioctl-number.txt | 2 +
MAINTAINERS | 8 +
drivers/Kconfig | 2 +
drivers/Makefile | 1 +
drivers/jtag/Kconfig | 17 ++
drivers/jtag/Makefile | 1 +
drivers/jtag/jtag.c | 274 ++++++++++++++++++++++++++++++++++
include/linux/jtag.h | 41 +++++
include/uapi/linux/jtag.h | 109 ++++++++++++++
9 files changed, 455 insertions(+), 0 deletions(-)
create mode 100644 drivers/jtag/Kconfig
create mode 100644 drivers/jtag/Makefile
create mode 100644 drivers/jtag/jtag.c
create mode 100644 include/linux/jtag.h
create mode 100644 include/uapi/linux/jtag.h
diff --git a/Documentation/ioctl/ioctl-number.txt b/Documentation/ioctl/ioctl-number.txt
index 7f7413e..886e676 100644
--- a/Documentation/ioctl/ioctl-number.txt
+++ b/Documentation/ioctl/ioctl-number.txt
@@ -318,6 +318,8 @@ Code Seq#(hex) Include File Comments
0xB0 all RATIO devices in development:
<mailto:vgo@ratio.de>
0xB1 00-1F PPPoX <mailto:mostrows@styx.uwaterloo.ca>
+0xB2 00-0F linux/jtag.h JTAG driver
+ <mailto:oleksandrs@mellanox.com>
0xB3 00 linux/mmc/ioctl.h
0xB4 00-0F linux/gpio.h <mailto:linux-gpio@vger.kernel.org>
0xB5 00-0F uapi/linux/rpmsg.h <mailto:linux-remoteproc@vger.kernel.org>
diff --git a/MAINTAINERS b/MAINTAINERS
index 79bb02f..e7b8b2c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7610,6 +7610,14 @@ L: linux-serial at vger.kernel.org
S: Maintained
F: drivers/tty/serial/jsm/
+JTAG SUBSYSTEM
+M: Oleksandr Shamray <oleksandrs@mellanox.com>
+M: Vadim Pasternak <vadimp@mellanox.com>
+S: Maintained
+F: include/linux/jtag.h
+F: include/uapi/linux/jtag.h
+F: drivers/jtag/
+
K10TEMP HARDWARE MONITORING DRIVER
M: Clemens Ladisch <clemens@ladisch.de>
L: linux-hwmon at vger.kernel.org
diff --git a/drivers/Kconfig b/drivers/Kconfig
index 95b9ccc..bb71e48 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -217,4 +217,6 @@ source "drivers/siox/Kconfig"
source "drivers/slimbus/Kconfig"
+source "drivers/jtag/Kconfig"
+
endmenu
diff --git a/drivers/Makefile b/drivers/Makefile
index 24cd470..c92636b 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -185,3 +185,4 @@ obj-$(CONFIG_TEE) += tee/
obj-$(CONFIG_MULTIPLEXER) += mux/
obj-$(CONFIG_UNISYS_VISORBUS) += visorbus/
obj-$(CONFIG_SIOX) += siox/
+obj-$(CONFIG_JTAG) += jtag/
diff --git a/drivers/jtag/Kconfig b/drivers/jtag/Kconfig
new file mode 100644
index 0000000..47771fc
--- /dev/null
+++ b/drivers/jtag/Kconfig
@@ -0,0 +1,17 @@
+menuconfig JTAG
+ tristate "JTAG support"
+ help
+ This provides basic core functionality support for JTAG class devices.
+ Hardware that is equipped with a JTAG microcontroller can be
+ supported by using this driver's interfaces.
+ This driver exposes a set of IOCTLs to the user space for
+ the following commands:
+ SDR: Performs an IEEE 1149.1 Data Register scan
+ SIR: Performs an IEEE 1149.1 Instruction Register scan.
+ RUNTEST: Forces the IEEE 1149.1 bus to a run state for a specified
+ number of clocks or a specified time period.
+
+ If you want this support, you should say Y here.
+
+ To compile this driver as a module, choose M here: the module will
+ be called jtag.
diff --git a/drivers/jtag/Makefile b/drivers/jtag/Makefile
new file mode 100644
index 0000000..af37493
--- /dev/null
+++ b/drivers/jtag/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_JTAG) += jtag.o
diff --git a/drivers/jtag/jtag.c b/drivers/jtag/jtag.c
new file mode 100644
index 0000000..6657b84
--- /dev/null
+++ b/drivers/jtag/jtag.c
@@ -0,0 +1,274 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// drivers/jtag/jtag.c
+//
+// Copyright (c) 2018 Mellanox Technologies. All rights reserved.
+// Copyright (c) 2018 Oleksandr Shamray <oleksandrs@mellanox.com>
+
+#include <linux/cdev.h>
+#include <linux/device.h>
+#include <linux/jtag.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/rtnetlink.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+#include <uapi/linux/jtag.h>
+
+struct jtag {
+ struct miscdevice miscdev;
+ const struct jtag_ops *ops;
+ int id;
+ unsigned long priv[0];
+};
+
+static DEFINE_IDA(jtag_ida);
+
+void *jtag_priv(struct jtag *jtag)
+{
+ return jtag->priv;
+}
+EXPORT_SYMBOL_GPL(jtag_priv);
+
+static long jtag_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ struct jtag *jtag = file->private_data;
+ struct jtag_run_test_idle idle;
+ struct jtag_xfer xfer;
+ u8 *xfer_data;
+ u32 data_size;
+ u32 value;
+ int err;
+
+ if (!arg)
+ return -EINVAL;
+
+ switch (cmd) {
+ case JTAG_GIOCFREQ:
+ if (!jtag->ops->freq_get)
+ return -EOPNOTSUPP;
+
+ err = jtag->ops->freq_get(jtag, &value);
+ if (err)
+ break;
+
+ if (put_user(value, (__u32 __user *)arg))
+ err = -EFAULT;
+ break;
+
+ case JTAG_SIOCFREQ:
+ if (!jtag->ops->freq_set)
+ return -EOPNOTSUPP;
+
+ if (get_user(value, (__u32 __user *)arg))
+ return -EFAULT;
+ if (value == 0)
+ return -EINVAL;
+
+ err = jtag->ops->freq_set(jtag, value);
+ break;
+
+ case JTAG_IOCRUNTEST:
+ if (copy_from_user(&idle, (const void __user *)arg,
+ sizeof(struct jtag_run_test_idle)))
+ return -EFAULT;
+
+ if (idle.endstate > JTAG_STATE_PAUSEDR)
+ return -EINVAL;
+
+ if (idle.reset > JTAG_FORCE_RESET)
+ return -EINVAL;
+
+ err = jtag->ops->idle(jtag, &idle);
+ break;
+
+ case JTAG_IOCXFER:
+ if (copy_from_user(&xfer, (const void __user *)arg,
+ sizeof(struct jtag_xfer)))
+ return -EFAULT;
+
+ if (xfer.length >= JTAG_MAX_XFER_DATA_LEN)
+ return -EINVAL;
+
+ if (xfer.type > JTAG_SDR_XFER)
+ return -EINVAL;
+
+ if (xfer.direction > JTAG_WRITE_XFER)
+ return -EINVAL;
+
+ if (xfer.endstate > JTAG_STATE_PAUSEDR)
+ return -EINVAL;
+
+ data_size = DIV_ROUND_UP(xfer.length, BITS_PER_BYTE);
+ xfer_data = memdup_user(u64_to_user_ptr(xfer.tdio), data_size);
+ if (IS_ERR(xfer_data))
+ return -EFAULT;
+
+ err = jtag->ops->xfer(jtag, &xfer, xfer_data);
+ if (err) {
+ kfree(xfer_data);
+ return err;
+ }
+
+ err = copy_to_user(u64_to_user_ptr(xfer.tdio),
+ (void *)xfer_data, data_size);
+ kfree(xfer_data);
+ if (err)
+ return -EFAULT;
+
+ if (copy_to_user((void __user *)arg, (void *)&xfer,
+ sizeof(struct jtag_xfer)))
+ return -EFAULT;
+ break;
+
+ case JTAG_GIOCSTATUS:
+ err = jtag->ops->status_get(jtag, &value);
+ if (err)
+ break;
+
+ err = put_user(value, (__u32 __user *)arg);
+ break;
+ case JTAG_SIOCMODE:
+ if (!jtag->ops->mode_set)
+ return -EOPNOTSUPP;
+
+ if (get_user(value, (__u32 __user *)arg))
+ return -EFAULT;
+ if (value == 0)
+ return -EINVAL;
+
+ err = jtag->ops->mode_set(jtag, value);
+ break;
+
+ default:
+ return -EINVAL;
+ }
+ return err;
+}
+
+static int jtag_open(struct inode *inode, struct file *file)
+{
+ struct jtag *jtag = container_of(file->private_data, struct jtag, miscdev);
+
+ file->private_data = jtag;
+ return nonseekable_open(inode, file);
+}
+
+static const struct file_operations jtag_fops = {
+ .owner = THIS_MODULE,
+ .open = jtag_open,
+ .llseek = noop_llseek,
+ .unlocked_ioctl = jtag_ioctl,
+};
+
+struct jtag *jtag_alloc(struct device *host, size_t priv_size,
+ const struct jtag_ops *ops)
+{
+ struct jtag *jtag;
+
+ if (!host)
+ return NULL;
+
+ if (!ops)
+ return NULL;
+
+ if (!ops->idle || !ops->status_get || !ops->xfer)
+ return NULL;
+
+ jtag = kzalloc(sizeof(*jtag) + priv_size, GFP_KERNEL);
+ if (!jtag)
+ return NULL;
+
+ jtag->ops = ops;
+ jtag->miscdev.parent = host;
+
+ return jtag;
+}
+EXPORT_SYMBOL_GPL(jtag_alloc);
+
+void jtag_free(struct jtag *jtag)
+{
+ kfree(jtag);
+}
+EXPORT_SYMBOL_GPL(jtag_free);
+
+static int jtag_register(struct jtag *jtag)
+{
+ struct device *dev = jtag->miscdev.parent;
+ int err;
+ int id;
+
+ if (!dev)
+ return -ENODEV;
+
+ id = ida_simple_get(&jtag_ida, 0, 0, GFP_KERNEL);
+ if (id < 0)
+ return id;
+
+ jtag->id = id;
+
+ jtag->miscdev.fops = &jtag_fops;
+ jtag->miscdev.minor = MISC_DYNAMIC_MINOR;
+ jtag->miscdev.name = kasprintf(GFP_KERNEL, "jtag%d", id);
+ if (!jtag->miscdev.name) {
+ err = -ENOMEM;
+ goto err_jtag_alloc;
+ }
+
+ err = misc_register(&jtag->miscdev);
+ if (err) {
+ dev_err(jtag->miscdev.parent, "Unable to register device\n");
+ goto err_jtag_name;
+ }
+ return 0;
+
+err_jtag_name:
+ kfree(jtag->miscdev.name);
+err_jtag_alloc:
+ ida_simple_remove(&jtag_ida, id);
+ return err;
+}
+
+static void jtag_unregister(struct jtag *jtag)
+{
+ misc_deregister(&jtag->miscdev);
+ kfree(jtag->miscdev.name);
+ ida_simple_remove(&jtag_ida, jtag->id);
+}
+
+static void devm_jtag_unregister(struct device *dev, void *res)
+{
+ jtag_unregister(*(struct jtag **)res);
+}
+
+int devm_jtag_register(struct device *dev, struct jtag *jtag)
+{
+ struct jtag **ptr;
+ int ret;
+
+ ptr = devres_alloc(devm_jtag_unregister, sizeof(*ptr), GFP_KERNEL);
+ if (!ptr)
+ return -ENOMEM;
+
+ ret = jtag_register(jtag);
+ if (!ret) {
+ *ptr = jtag;
+ devres_add(dev, ptr);
+ } else {
+ devres_free(ptr);
+ }
+ return ret;
+}
+EXPORT_SYMBOL_GPL(devm_jtag_register);
+
+static void __exit jtag_exit(void)
+{
+ ida_destroy(&jtag_ida);
+}
+
+module_exit(jtag_exit);
+
+MODULE_AUTHOR("Oleksandr Shamray <oleksandrs@mellanox.com>");
+MODULE_DESCRIPTION("Generic jtag support");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/jtag.h b/include/linux/jtag.h
new file mode 100644
index 0000000..fd5dd79
--- /dev/null
+++ b/include/linux/jtag.h
@@ -0,0 +1,41 @@
+// SPDX-License-Identifier: GPL-2.0
+// include/linux/jtag.h - JTAG class driver
+//
+// Copyright (c) 2018 Mellanox Technologies. All rights reserved.
+// Copyright (c) 2018 Oleksandr Shamray <oleksandrs@mellanox.com>
+
+#ifndef __JTAG_H
+#define __JTAG_H
+
+#include <linux/types.h>
+#include <uapi/linux/jtag.h>
+
+#define JTAG_MAX_XFER_DATA_LEN 65535
+
+struct jtag;
+/**
+ * struct jtag_ops - callbacks for JTAG control functions:
+ *
+ * @freq_get: get frequency function. Filled by dev driver
+ * @freq_set: set frequency function. Filled by dev driver
+ * @status_get: set status function. Mandatory func. Filled by dev driver
+ * @idle: set JTAG to idle state function. Mandatory func. Filled by dev driver
+ * @xfer: send JTAG xfer function. Mandatory func. Filled by dev driver
+ * @mode_set: set specific work mode for JTAG. Filled by dev driver
+ */
+struct jtag_ops {
+ int (*freq_get)(struct jtag *jtag, u32 *freq);
+ int (*freq_set)(struct jtag *jtag, u32 freq);
+ int (*status_get)(struct jtag *jtag, u32 *state);
+ int (*idle)(struct jtag *jtag, struct jtag_run_test_idle *idle);
+ int (*xfer)(struct jtag *jtag, struct jtag_xfer *xfer, u8 *xfer_data);
+ int (*mode_set)(struct jtag *jtag, u32 mode_mask);
+};
+
+void *jtag_priv(struct jtag *jtag);
+int devm_jtag_register(struct device *dev, struct jtag *jtag);
+struct jtag *jtag_alloc(struct device *host, size_t priv_size,
+ const struct jtag_ops *ops);
+void jtag_free(struct jtag *jtag);
+
+#endif /* __JTAG_H */
diff --git a/include/uapi/linux/jtag.h b/include/uapi/linux/jtag.h
new file mode 100644
index 0000000..79f72bf
--- /dev/null
+++ b/include/uapi/linux/jtag.h
@@ -0,0 +1,109 @@
+// SPDX-License-Identifier: GPL-2.0
+// include/uapi/linux/jtag.h - JTAG class driver uapi
+//
+// Copyright (c) 2018 Mellanox Technologies. All rights reserved.
+// Copyright (c) 2018 Oleksandr Shamray <oleksandrs@mellanox.com>
+
+#ifndef __UAPI_LINUX_JTAG_H
+#define __UAPI_LINUX_JTAG_H
+
+/*
+ * JTAG_XFER_HW_MODE: JTAG hardware mode. Used to set HW drived or bitbang
+ * mode. This is bitmask param of ioctl JTAG_SIOCMODE command
+ */
+#define JTAG_XFER_HW_MODE 1
+
+/**
+ * enum jtag_endstate:
+ *
+ * @JTAG_STATE_IDLE: JTAG state machine IDLE state
+ * @JTAG_STATE_PAUSEIR: JTAG state machine PAUSE_IR state
+ * @JTAG_STATE_PAUSEDR: JTAG state machine PAUSE_DR state
+ */
+enum jtag_endstate {
+ JTAG_STATE_IDLE,
+ JTAG_STATE_PAUSEIR,
+ JTAG_STATE_PAUSEDR,
+};
+
+/**
+ * enum jtag_reset:
+ *
+ * @JTAG_NO_RESET: JTAG run TAP from current state
+ * @JTAG_FORCE_RESET: JTAG force TAP to reset state
+ */
+enum jtag_reset {
+ JTAG_NO_RESET,
+ JTAG_FORCE_RESET,
+};
+
+/**
+ * enum jtag_xfer_type:
+ *
+ * @JTAG_SIR_XFER: SIR transfer
+ * @JTAG_SDR_XFER: SDR transfer
+ */
+enum jtag_xfer_type {
+ JTAG_SIR_XFER,
+ JTAG_SDR_XFER,
+};
+
+/**
+ * enum jtag_xfer_direction:
+ *
+ * @JTAG_READ_XFER: read transfer
+ * @JTAG_WRITE_XFER: write transfer
+ */
+enum jtag_xfer_direction {
+ JTAG_READ_XFER,
+ JTAG_WRITE_XFER,
+};
+
+/**
+ * struct jtag_run_test_idle - forces JTAG state machine to
+ * RUN_TEST/IDLE state
+ *
+ * @reset: 0 - run IDLE/PAUSE from current state
+ * 1 - go through TEST_LOGIC/RESET state before IDLE/PAUSE
+ * @end: completion flag
+ * @tck: clock counter
+ *
+ * Structure provide interface to JTAG device for JTAG IDLE execution.
+ */
+struct jtag_run_test_idle {
+ __u8 reset;
+ __u8 endstate;
+ __u8 tck;
+};
+
+/**
+ * struct jtag_xfer - jtag xfer:
+ *
+ * @type: transfer type
+ * @direction: xfer direction
+ * @length: xfer bits len
+ * @tdio : xfer data array
+ * @endir: xfer end state
+ *
+ * Structure provide interface to JTAG device for JTAG SDR/SIR xfer execution.
+ */
+struct jtag_xfer {
+ __u8 type;
+ __u8 direction;
+ __u8 endstate;
+ __u8 padding;
+ __u32 length;
+ __u64 tdio;
+};
+
+/* ioctl interface */
+#define __JTAG_IOCTL_MAGIC 0xb2
+
+#define JTAG_IOCRUNTEST _IOW(__JTAG_IOCTL_MAGIC, 0, struct jtag_run_test_idle)
+#define JTAG_SIOCFREQ _IOW(__JTAG_IOCTL_MAGIC, 1, unsigned int)
+#define JTAG_GIOCFREQ _IOR(__JTAG_IOCTL_MAGIC, 2, unsigned int)
+#define JTAG_IOCXFER _IOWR(__JTAG_IOCTL_MAGIC, 3, struct jtag_xfer)
+#define JTAG_GIOCSTATUS _IOWR(__JTAG_IOCTL_MAGIC, 4, enum jtag_endstate)
+#define JTAG_SIOCMODE _IOW(__JTAG_IOCTL_MAGIC, 5, unsigned int)
+
+#endif /* __UAPI_LINUX_JTAG_H */
--
1.7.1
^ permalink raw reply related
* [patch v24 0/4] JTAG driver introduction
From: Oleksandr Shamray @ 2018-05-29 12:58 UTC (permalink / raw)
To: linux-arm-kernel
When a need raise up to use JTAG interface for system's devices
programming or CPU debugging, usually the user layer
application implements jtag protocol by bit-bang or using a
proprietary connection to vendor hardware.
This method can be slow and not generic.
We propose to implement general JTAG interface and infrastructure
to communicate with user layer application. In such way, we can
have the standard JTAG interface core part and separation from
specific HW implementation.
This allow new capability to debug the CPU or program system's
device via BMC without additional devices nor cost.
This patch purpose is to add JTAG master core infrastructure by
defining new JTAG class and provide generic JTAG interface
to allow hardware specific drivers to connect this interface.
This will enable all JTAG drivers to use the common interface
part and will have separate for hardware implementation.
The JTAG (Joint Test Action Group) core driver provides minimal generic
JTAG interface, which can be used by hardware specific JTAG master
controllers. By providing common interface for the JTAG controllers,
user space device programing is hardware independent.
Modern SoC which in use for embedded system' equipped with
internal JTAG master interface.
This interface is used for programming and debugging system's
hardware components, like CPLD, FPGA, CPU, voltage and
industrial controllers.
Firmware for such devices can be upgraded through JTAG interface during
Runtime. The JTAG standard support for multiple devices programming,
is in case their lines are daisy-chained together.
For example, systems which equipped with host CPU, BMC SoC or/and
number of programmable devices are capable to connect a pin and
select system components dynamically for programming and debugging,
This is using by the BMC which is equipped with internal SoC master
controller.
For example:
BMC JTAG master --> pin selected to CPLDs chain for programming (filed
upgrade, production)
BMC JTAG master --> pin selected to voltage monitors for programming
(field upgrade, production)
BMC JTAG master --> pin selected to host CPU (on-site debugging
and developers debugging)
For example, we can have application in user space which using calls
to JTAG driver executes CPLD programming directly from SVF file
The JTAG standard (IEEE 1149.1) defines the next connector pins:
- TDI (Test Data In);
- TDO (Test Data Out);
- TCK (Test Clock);
- TMS (Test Mode Select);
- TRST (Test Reset) (Optional);
The SoC equipped with JTAG master controller, performs
device programming on command or vector level. For example
a file in a standard SVF (Serial Vector Format) that contains
boundary scan vectors, can be used by sending each vector
to the JTAG interface and the JTAG controller will execute
the programming.
Initial version provides the system calls set for:
- SIR (Scan Instruction Register, IEEE 1149.1 Instruction Register scan);
- SDR (Scan Data Register, IEEE 1149.1 Data Register scan);
- RUNTEST (Forces the IEEE 1149.1 bus to a run state for a specified
number of clocks.
SoC which are not equipped with JTAG master interface, can be built
on top of JTAG core driver infrastructure, by applying bit-banging of
TDI, TDO, TCK and TMS pins within the hardware specific driver.
Oleksandr Shamray (4):
drivers: jtag: Add JTAG core driver
drivers: jtag: Add Aspeed SoC 24xx and 25xx families JTAG master
driver
Documentation: jtag: Add bindings for Aspeed SoC 24xx and 25xx
families JTAG master driver
Documentation: jtag: Add ABI documentation
Documentation/ABI/testing/jtag-dev | 27 +
.../devicetree/bindings/jtag/aspeed-jtag.txt | 22 +
Documentation/ioctl/ioctl-number.txt | 2 +
Documentation/jtag/overview | 27 +
Documentation/jtag/transactions | 109 +++
MAINTAINERS | 10 +
drivers/Kconfig | 2 +
drivers/Makefile | 1 +
drivers/jtag/Kconfig | 31 +
drivers/jtag/Makefile | 2 +
drivers/jtag/jtag-aspeed.c | 769 ++++++++++++++++++++
drivers/jtag/jtag.c | 274 +++++++
include/linux/jtag.h | 41 +
include/uapi/linux/jtag.h | 109 +++
14 files changed, 1426 insertions(+), 0 deletions(-)
create mode 100644 Documentation/ABI/testing/jtag-dev
create mode 100644 Documentation/devicetree/bindings/jtag/aspeed-jtag.txt
create mode 100644 Documentation/jtag/overview
create mode 100644 Documentation/jtag/transactions
create mode 100644 drivers/jtag/Kconfig
create mode 100644 drivers/jtag/Makefile
create mode 100644 drivers/jtag/jtag-aspeed.c
create mode 100644 drivers/jtag/jtag.c
create mode 100644 include/linux/jtag.h
create mode 100644 include/uapi/linux/jtag.h
^ permalink raw reply
* [PATCH v2 3/4] ARM: dts: imx6qdl-wandboard: enable USB OTG
From: Fabio Estevam @ 2018-05-29 12:58 UTC (permalink / raw)
To: linux-arm-kernel
In-Reply-To: <20180529062021.3154-4-akurz@blala.de>
On Tue, May 29, 2018 at 3:20 AM, Alexander Kurz <akurz@blala.de> wrote:
> Enable USB OTG (dual-role) on the Wandboard.
> Note, that the USB_OTG_VBUS current is quite limited due to a 22R resistor
> in the power line. Hence, the overcurrent signal of 1A will never be
> triggered on this board.
>
> Signed-off-by: Alexander Kurz <akurz@blala.de>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
^ permalink raw reply
* [PATCH v2 2/4] ARM: dts: imx6dl-riotboard: remove regulators bus node
From: Fabio Estevam @ 2018-05-29 12:53 UTC (permalink / raw)
To: linux-arm-kernel
In-Reply-To: <20180529062021.3154-3-akurz@blala.de>
On Tue, May 29, 2018 at 3:20 AM, Alexander Kurz <akurz@blala.de> wrote:
> To match the convention, move regulator-fixed nodes directly into
> the root node.
>
> Signed-off-by: Alexander Kurz <akurz@blala.de>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
^ permalink raw reply
* [PATCH v2 1/4] ARM: dts: imx6qdl-wandboard: remove regulators bus node
From: Fabio Estevam @ 2018-05-29 12:53 UTC (permalink / raw)
To: linux-arm-kernel
In-Reply-To: <20180529062021.3154-2-akurz@blala.de>
On Tue, May 29, 2018 at 3:20 AM, Alexander Kurz <akurz@blala.de> wrote:
> To match the convention, move all regulator-fixed nodes directly into
> the root node.
>
> Signed-off-by: Alexander Kurz <akurz@blala.de>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
^ permalink raw reply
* [PATCH 1/4] ARM: dts: Restructure Vexpress motherboard includes
From: Sudeep Holla @ 2018-05-29 12:34 UTC (permalink / raw)
To: linux-arm-kernel
In-Reply-To: <CACRpkdZvM+2cZ3JKqzJx_1VPgc=CEkMFgwjo9h6v0E8rckuNDw@mail.gmail.com>
On 29/05/18 12:48, Linus Walleij wrote:
> On Tue, May 29, 2018 at 11:25 AM, Sudeep Holla <sudeep.holla@arm.com> wrote:
>> On 28/05/18 13:26, Linus Walleij wrote:
>
>>> This is a purely syntactic change that result in the same
>>> DTB files from the DTS/DTSI files.
>
>> Is it different from v1/earlier version you had posted ?
>
> Don't think so. Just resent it as part of the rest.
>
>> I have already sent this to ARM SoC and it should be in -next by now.
>
> Awesome!
>
>> I will add the remaining 3 patches for v4.19 once you confirm
>> that I can drop this patch as it's already queued.
>
> Drop it :)
>
Thanks, will apply the remaining patches once v4.18-rc1 is tagged.
--
Regards,
Sudeep
^ permalink raw reply
* [PATCH v2 13/40] vfio: Add support for Shared Virtual Addressing
From: Xu Zaibo @ 2018-05-29 12:24 UTC (permalink / raw)
To: linux-arm-kernel
In-Reply-To: <99ff4f89-86ef-a251-894c-8aa8a47d2a69@arm.com>
Hi,
On 2018/5/29 19:55, Jean-Philippe Brucker wrote:
> (If possible, please reply in plain text to the list. Reading this in a
> text-only reader is confusing, because all quotes have the same level)
Sorry for that? I have reset the thunderbird, :) thanks.
> On 26/05/18 04:53, Xu Zaibo wrote:
>> I guess there may be some misunderstandings :).
>>
>> From the current patches, 'iommu_sva_device_shutdown' is called by 'vfio_iommu_sva_shutdown', which
>> is mainly used by 'vfio_iommu_type1_detach_group' that is finally called by processes' release of vfio facilitiy
>> automatically or called by 'VFIO_GROUP_UNSET_CONTAINER' manually in the processes.
>>
>> So, just image that 2 processes is working on the device with IOPF feature, and the 2 do the following to enable SVA:
>>
>> 1.open("/dev/vfio/vfio") ;
>>
>> 2.open the group of the devcie by calling open("/dev/vfio/x"), but now,
>> I think the second processes will fail to open the group because current VFIO thinks that one group only can be used by one process/vm,
>> at present, I use mediated device to create more groups on the parent device to support multiple processes;
>>
>> 3.VFIO_GROUP_SET_CONTAINER;
>>
>> 4.VFIO_SET_IOMMU;
>>
>> 5.VFIO_IOMMU_BIND;
> I have a concern regarding your driver. With mdev you can't allow
> processes to program the PASID themselves, since the parent device has a
> single PASID table. You lose all isolation since processes could write
> any value in the PASID field and access address spaces of other
> processes bound to this parent device (even if the BIND call was for
> other mdevs).
Yes, if wrapdrive do nothing on this PASID setting procedure in kernel
space, I think
there definitely exists this security risk.
> The wrap driver has to mediate calls to bind(), and either program the
> PASID into the device itself, or at least check that, when receiving a
> SET_PASID ioctl from a process, the given PASID was actually allocated
> to the process.
Yes, good advice, thanks.
>
>> 6.Do some works with the hardware working unit filled by PASID on the device;
>>
>> 7.VFIO_IOMMU_UNBIND;
>>
>> 8.VFIO_GROUP_UNSET_CONTAINER;---here, have to sleep to wait another process to finish works of the step 6;
>>
>> 9. close(group); close(containner);
>>
>>
>> So, my idea is: If it is possible to just release the params or facilities that only belong to the current process while the process shutdown the device,
>> and while the last process releases them all. Then, as in the above step 8, we
>> don't need to wait, or maybe wait for a very long time if the other process is doing lots of work on the device.
> Given that you need to notify the mediating driver of IOMMU_BIND calls
> as explained above, you could do something similar for shutdown: from
> the mdev driver, call iommu_sva_shutdown_device() only for the last mdev.
Currently, I add an API to check if it is the last mdev in wrapdrive, as
vfio shutdowns the device,
it call the API to do the check at first.
Thanks
Zaibo
^ permalink raw reply
* linux-next: manual merge of the irqchip tree with the arm-soc tree
From: Ludovic BARRE @ 2018-05-29 12:20 UTC (permalink / raw)
To: linux-arm-kernel
In-Reply-To: <b8fa6cc9-5d73-81a2-25b8-f0c858ef0c62@st.com>
On 05/29/2018 10:55 AM, Alexandre Torgue wrote:
>
>
> On 05/29/2018 10:39 AM, Marc Zyngier wrote:
>> On 29/05/18 09:16, Alexandre Torgue wrote:
>>> Hi Marc
>>>
>>> On 05/29/2018 09:47 AM, Marc Zyngier wrote:
>>>> On 29/05/18 08:41, Alexandre Torgue wrote:
>>>>> Hi Stephen
>>>>>
>>>>> On 05/29/2018 07:52 AM, Stephen Rothwell wrote:
>>>>>> Hi all,
>>>>>>
>>>>>> Today's linux-next merge of the irqchip tree got a conflict in:
>>>>>>
>>>>>> ???? arch/arm/boot/dts/stm32mp157c.dtsi
>>>>>>
>>>>>> between commit:
>>>>>>
>>>>>> ???? 3c00436fdb20 ("ARM: dts: stm32: add USBPHYC support to
>>>>>> stm32mp157c")
>>>>>>
>>>>>> from the arm-soc tree and commit:
>>>>>>
>>>>>> ???? 5f0e9d2557d7 ("ARM: dts: stm32: Add exti support for
>>>>>> stm32mp157c")
>>>>>>
>>>>>> from the irqchip tree.
>>>>>>
>>>>>> I fixed it up (see below) and can carry the fix as necessary. This
>>>>>> is now fixed as far as linux-next is concerned, but any non trivial
>>>>>> conflicts should be mentioned to your upstream maintainer when
>>>>>> your tree
>>>>>> is submitted for merging.? You may also want to consider cooperating
>>>>>> with the maintainer of the conflicting tree to minimise any
>>>>>> particularly
>>>>>> complex conflicts.
>>>>>>
>>>>>
>>>>> Thanks for the fix (I will reorder nodes in a future patch). My
>>>>> opinion
>>>>> is that all STM32 DT patches should come through my STM32 tree. It
>>>>> is my
>>>>> role to fix this kind of conflicts. I thought it was a common rule
>>>>> (driver patches go to sub-system maintainer tree and DT to the Machine
>>>>> maintainer). For incoming next-series which contain DT+driver
>>>>> patches I
>>>>> will indicate clearly that I take DT patch. I'm right ?
>>>> Happy to oblige. Can you make sure you sync up with Ludovic and define
>>>> what you want to do?
>>>
>>> Sorry I don't understand your reply. I just say that for series
>>> containing DT patches + drivers patches, to my point of view it is more
>>> safe that driver patches are taken by sub-system maintainer (you in this
>>> case) and that I take DT patches in my tree.
>> And I'm happy to let you deal with these patches. I'm just asking you
>> sync with Ludovic to split the series on whichever boundary you wish to
>> enforce.
> ok
>
>>
>>>> In the meantime, I'm dropping the series altogether.
>>>>
>>> Why? We could keep it as Stephen fixed the merge issue.
>> Well, you seem to have a strong opinion about who deals with what. I'll
>> let Ludovic repost what you and him decide should go via the irqchip
>> tree.
>
> It's not a "strong" opinion just my point of view and maybe not the good
> one. I thought that's the way of working was like I explained. If you
> prefer 2 series (one for driver patches and another one for DT patches)
> I will be happy with that.
>
> Ludovic, what is your opinion ?
Hi everybody
For this serie, I think we could keep like that with
Stephen fix. New stm32 irqchip will be integrated (thanks Marc)
with no conflict with usb (thanks Stephen).
For next series, we may split driver and DT to avoid misunderstanding.
BR
Ludo
>
> Regards
> Alexandre
>
>>
>> Thanks,
>>
>> ????M.
>>
^ permalink raw reply
* [PATCH v2 4/4] mmc: sdhci-msm: Add sdhci msm register write APIs which wait for pwr irq
From: Georgi Djakov @ 2018-05-29 12:19 UTC (permalink / raw)
To: linux-arm-kernel
In-Reply-To: <1506490483-46871-5-git-send-email-vviswana@codeaurora.org>
Hello Vijay,
On 09/27/2017 08:34 AM, Vijay Viswanath wrote:
> Register writes which change voltage of IO lines or turn the IO bus
> on/off require controller to be ready before progressing further. When
> the controller is ready, it will generate a power irq which needs to be
> handled. The thread which initiated the register write should wait for
> power irq to complete. This will be done through the new sdhc msm write
> APIs which will check whether the particular write can trigger a power
> irq and wait for it with a timeout if it is expected.
> The SDHC core power control IRQ gets triggered when -
> * There is a state change in power control bit (bit 0)
> of SDHCI_POWER_CONTROL register.
> * There is a state change in 1.8V enable bit (bit 3) of
> SDHCI_HOST_CONTROL2 register.
> * Bit 1 of SDHCI_SOFTWARE_RESET is set.
>
> Also add support APIs which are used by sdhc msm write APIs to check
> if power irq is expected to be generated and wait for the power irq
> to come and complete if the irq is expected.
>
> This patch requires CONFIG_MMC_SDHCI_IO_ACCESSORS to be enabled.
>
> Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
> Signed-off-by: Vijay Viswanath <vviswana@codeaurora.org>
> ---
> drivers/mmc/host/sdhci-msm.c | 173 ++++++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 171 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
[..]
> +/*
> + * sdhci_msm_check_power_status API should be called when registers writes
> + * which can toggle sdhci IO bus ON/OFF or change IO lines HIGH/LOW happens.
> + * To what state the register writes will change the IO lines should be passed
> + * as the argument req_type. This API will check whether the IO line's state
> + * is already the expected state and will wait for power irq only if
> + * power irq is expected to be trigerred based on the current IO line state
> + * and expected IO line state.
> + */
> +static void sdhci_msm_check_power_status(struct sdhci_host *host, u32 req_type)
> +{
> + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> + struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
> + bool done = false;
> +
> + pr_debug("%s: %s: request %d curr_pwr_state %x curr_io_level %x\n",
> + mmc_hostname(host->mmc), __func__, req_type,
> + msm_host->curr_pwr_state, msm_host->curr_io_level);
> +
> + /*
> + * The IRQ for request type IO High/LOW will be generated when -
> + * there is a state change in 1.8V enable bit (bit 3) of
> + * SDHCI_HOST_CONTROL2 register. The reset state of that bit is 0
> + * which indicates 3.3V IO voltage. So, when MMC core layer tries
> + * to set it to 3.3V before card detection happens, the
> + * IRQ doesn't get triggered as there is no state change in this bit.
> + * The driver already handles this case by changing the IO voltage
> + * level to high as part of controller power up sequence. Hence, check
> + * for host->pwr to handle a case where IO voltage high request is
> + * issued even before controller power up.
> + */
> + if ((req_type & REQ_IO_HIGH) && !host->pwr) {
> + pr_debug("%s: do not wait for power IRQ that never comes, req_type: %d\n",
> + mmc_hostname(host->mmc), req_type);
> + return;
> + }
> + if ((req_type & msm_host->curr_pwr_state) ||
> + (req_type & msm_host->curr_io_level))
> + done = true;
> + /*
> + * This is needed here to handle cases where register writes will
> + * not change the current bus state or io level of the controller.
> + * In this case, no power irq will be triggerred and we should
> + * not wait.
> + */
> + if (!done) {
> + if (!wait_event_timeout(msm_host->pwr_irq_wait,
> + msm_host->pwr_irq_flag,
> + msecs_to_jiffies(MSM_PWR_IRQ_TIMEOUT_MS)))
> + __WARN_printf("%s: pwr_irq for req: (%d) timed out\n",
> + mmc_hostname(host->mmc), req_type);
I am seeing the above error message on a db820c device (apq8096). When i
unplug the SD card and then plug it back in, there is a 5 sec card
detection delay and a timeout. Here is a log:
[ 50.253997] mmc0: card 59b4 removed
[ 50.381874] mmc0: sdhci_msm_check_power_status: request 1
curr_pwr_state 2 curr_io_level 4 sdhci_host_ctrl2 b
[ 50.382656] mmc0: sdhci_msm_check_power_status: request 1 done
[ 50.392493] mmc0: sdhci_msm_check_power_status: request 4
curr_pwr_state 1 curr_io_level 4 sdhci_host_ctrl2 b
[ 50.398258] mmc0: sdhci_msm_check_power_status: request 4 done
[ 50.408728] mmc0: sdhci_msm_check_power_status: request 4
curr_pwr_state 1 curr_io_level 4 sdhci_host_ctrl2 8
[ 50.413865] mmc0: sdhci_msm_check_power_status: request 4 done
[ 54.966316] mmc0: sdhci_msm_check_power_status: request 2
curr_pwr_state 1 curr_io_level 4 sdhci_host_ctrl2 8 <-- card is plugged
[ 54.967756] mmc0: sdhci_msm_check_power_status: request 2 done
[ 54.976822] mmc0: sdhci_msm_check_power_status: request 4
curr_pwr_state 2 curr_io_level 8 sdhci_host_ctrl2 8
[ 60.132253] sdhci_msm 74a4900.sdhci: mmc0: pwr_irq for req: (4) timed out
[ 60.132782] mmc0: sdhci_msm_check_power_status: request 4 done
[ 60.139888] mmc0: sdhci_msm_check_power_status: request 4
curr_pwr_state 2 curr_io_level 8 sdhci_host_ctrl2 8
[ 65.252497] sdhci_msm 74a4900.sdhci: mmc0: pwr_irq for req: (4) timed out
The following patch seem to "fix" it.
-- >8 --
diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
index b2d875afae5f..ca8ad4edcf80 100644
--- a/drivers/mmc/host/sdhci-msm.c
+++ b/drivers/mmc/host/sdhci-msm.c
@@ -1049,6 +1049,11 @@ static void sdhci_msm_check_power_status(struct
sdhci_host *host, u32 req_type)
return;
}
+ if (req_type & REQ_IO_LOW &&
+ msm_host->curr_pwr_state & REQ_BUS_ON &&
+ msm_host->curr_io_level & REQ_IO_HIGH &&
+ !host->pwr)
+ done = true;
/*
* The IRQ for request type IO High/LOW will be generated when -
* there is a state change in 1.8V enable bit (bit 3) of
-- >8 --
Reverting this patch series or applying the above patch makes the issue
go away. According to the log, there is no change in the
sdhci_host_ctrl2 register. What do you think?
Thanks,
Georgi
^ permalink raw reply related
* [PATCH v2 17/17] arm64: ssbd: Implement arch_seccomp_spec_mitigate
From: Marc Zyngier @ 2018-05-29 12:11 UTC (permalink / raw)
To: linux-arm-kernel
In-Reply-To: <20180529121121.24927-1-marc.zyngier@arm.com>
Now that we have a way to safely implement TIF_SSBD for tasks
that are not in the kernel at the point were the flag gets
set, let's implement arch_seccomp_spec_mitigate().
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
arch/arm64/kernel/ssbd.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/arch/arm64/kernel/ssbd.c b/arch/arm64/kernel/ssbd.c
index 34eafdc7fb6b..a61da5e1b2ed 100644
--- a/arch/arm64/kernel/ssbd.c
+++ b/arch/arm64/kernel/ssbd.c
@@ -77,6 +77,13 @@ int arch_prctl_spec_ctrl_set(struct task_struct *task, unsigned long which,
}
}
+#ifdef CONFIG_SECCOMP
+void arch_seccomp_spec_mitigate(struct task_struct *task)
+{
+ ssbd_prctl_set(task, PR_SPEC_FORCE_DISABLE);
+}
+#endif
+
static int ssbd_prctl_get(struct task_struct *task)
{
switch (arm64_get_ssbd_state()) {
--
2.14.2
^ permalink raw reply related
* [PATCH v2 16/17] arm64: ssbd: Enable delayed setting of TIF_SSBD
From: Marc Zyngier @ 2018-05-29 12:11 UTC (permalink / raw)
To: linux-arm-kernel
In-Reply-To: <20180529121121.24927-1-marc.zyngier@arm.com>
Setting the TIF_SSBD flag on a seccomp thread can happen while the
thread is in userspace (a complete departure from the normal behaviour
of the prctl interface).
As a consequence, the kernel will not enable the mitigation when
transitioning from EL0 to EL1, as it relies on not seeing TIF_SSBD
to call into the firmware. Not exactly what we had planned.
As a way to solve this problem, let's introduce a new TIF_SSBD_PENDING
flag, which gets set on the userspace thread instead of TIF_SSBD.
On entering the kernel, the mitigation will be activated (as the
TIF_SSBD flag is not there). On exit to userspace, we check for the
pending flag, and if present, replace it with TIF_SSBD, leaving
the mitigation on.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
arch/arm64/include/asm/thread_info.h | 1 +
arch/arm64/kernel/entry.S | 16 ++++++++++++++++
arch/arm64/kernel/ssbd.c | 5 +++--
3 files changed, 20 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h
index cbcf11b5e637..e462e7332951 100644
--- a/arch/arm64/include/asm/thread_info.h
+++ b/arch/arm64/include/asm/thread_info.h
@@ -95,6 +95,7 @@ void arch_release_task_struct(struct task_struct *tsk);
#define TIF_SVE 23 /* Scalable Vector Extension in use */
#define TIF_SVE_VL_INHERIT 24 /* Inherit sve_vl_onexec across exec */
#define TIF_SSBD 25 /* Wants SSB mitigation */
+#define TIF_SSBD_PENDING 26 /* Sets TIF_SSB on exit to EL0 */
#define _TIF_SIGPENDING (1 << TIF_SIGPENDING)
#define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED)
diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index 28ad8799406f..550c793d9bc6 100644
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -896,12 +896,27 @@ el0_error_naked:
b ret_to_user
ENDPROC(el0_error)
+ .macro fixup_ssbd, tmp1, tmp2, wtmp
+#ifdef CONFIG_ARM64_SSBD
+alternative_cb arm64_enable_wa2_handling
+ b 2f
+alternative_cb_end
+ // If the thread is in the SSBD_PENDING state, move it to
+ // the SSBD state, ensuring that the mitigation stays on.
+ add \tmp2, tsk, #TSK_TI_FLAGS
+ test_and_clear_flag \tmp1, \tmp2, TIF_SSBD_PENDING, \wtmp
+ cbz \tmp1, 2f
+ set_flag \tmp2, TIF_SSBD, \tmp1, \wtmp
+2:
+#endif
+ .endm
/*
* This is the fast syscall return path. We do as little as possible here,
* and this includes saving x0 back into the kernel stack.
*/
ret_fast_syscall:
+ fixup_ssbd x20, x21 , w22
disable_daif
str x0, [sp, #S_X0] // returned x0
ldr x1, [tsk, #TSK_TI_FLAGS] // re-check for syscall tracing
@@ -930,6 +945,7 @@ work_pending:
* "slow" syscall return path.
*/
ret_to_user:
+ fixup_ssbd x20, x21, w22
disable_daif
ldr x1, [tsk, #TSK_TI_FLAGS]
and x2, x1, #_TIF_WORK_MASK
diff --git a/arch/arm64/kernel/ssbd.c b/arch/arm64/kernel/ssbd.c
index 07b12c034ec2..34eafdc7fb6b 100644
--- a/arch/arm64/kernel/ssbd.c
+++ b/arch/arm64/kernel/ssbd.c
@@ -43,20 +43,21 @@ static int ssbd_prctl_set(struct task_struct *task, unsigned long ctrl)
task_spec_ssb_force_disable(task))
return -EPERM;
task_clear_spec_ssb_disable(task);
+ clear_tsk_thread_flag(task, TIF_SSBD_PENDING);
clear_tsk_thread_flag(task, TIF_SSBD);
break;
case PR_SPEC_DISABLE:
if (state == ARM64_SSBD_FORCE_DISABLE)
return -EPERM;
task_set_spec_ssb_disable(task);
- set_tsk_thread_flag(task, TIF_SSBD);
+ set_tsk_thread_flag(task, TIF_SSBD_PENDING);
break;
case PR_SPEC_FORCE_DISABLE:
if (state == ARM64_SSBD_FORCE_DISABLE)
return -EPERM;
task_set_spec_ssb_disable(task);
task_set_spec_ssb_force_disable(task);
- set_tsk_thread_flag(task, TIF_SSBD);
+ set_tsk_thread_flag(task, TIF_SSBD_PENDING);
break;
default:
return -ERANGE;
--
2.14.2
^ permalink raw reply related
* [PATCH v2 15/17] arm64: Add test_and_clear_flag and set_flag atomic assembler primitives
From: Marc Zyngier @ 2018-05-29 12:11 UTC (permalink / raw)
To: linux-arm-kernel
In-Reply-To: <20180529121121.24927-1-marc.zyngier@arm.com>
As we're about to need to atomically manipulate some thread
flags from entry.S, let's introduce two atomic primitives
(test_and_clear_flag and set_flag) for that purpose.
We provide two implementations: one using the traditional
LL/SC instructions, and one using the ARMv8.1 atomics.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
arch/arm64/include/asm/assembler.h | 37 +++++++++++++++++++++++++++++++++++++
1 file changed, 37 insertions(+)
diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h
index 0bcc98dbba56..d3612ad8035e 100644
--- a/arch/arm64/include/asm/assembler.h
+++ b/arch/arm64/include/asm/assembler.h
@@ -26,6 +26,7 @@
#include <asm/asm-offsets.h>
#include <asm/cpufeature.h>
#include <asm/debug-monitors.h>
+#include <asm/lse.h>
#include <asm/page.h>
#include <asm/pgtable-hwdef.h>
#include <asm/ptrace.h>
@@ -701,4 +702,40 @@ USER(\label, ic ivau, \tmp2) // invalidate I line PoU
.Lyield_out_\@ :
.endm
+/*
+ * test_and_clear_flag:
+ *
+ * res: register containing the result (0 or 1 << bitnum)
+ * addr: address of the word to be manipulated
+ * bitnum: number of the bit in that word
+ * wtmp: temporary register, must be a 32bit reg
+ */
+ .macro test_and_clear_flag, res, addr, bitnum, wtmp
+alt_lse " prfm pstl1strm, [\addr]", "nop"
+alt_lse "8:ldxr \res, [\addr]", "ldr \res, [\addr]"
+ tbz \res, #\bitnum, 9f
+alt_lse " bic \res, \res, #(1 << \bitnum)", "mov \res, #(1 << \bitnum)"
+alt_lse " stlxr \wtmp, \res, [\addr]", "ldclral \res, \res, [\addr]"
+alt_lse " cbnz \wtmp, 8b", "nop"
+alt_lse " dmb ish", "nop"
+alt_lse " orr \res, \res, #(1 << \bitnum)", "nop"
+9:
+ .endm
+
+/*
+ * set_flag:
+ *
+ * addr: address of the word to be manipulated
+ * bitnum: number of the bit in that word
+ * tmp: temporary register
+ * wtmp: temporary register, must be a 32bit reg
+ */
+ .macro set_flag, addr, bitnum, tmp, wtmp
+alt_lse " prfm pstl1strm, [\addr]", "mov \tmp, #(1 << \bitnum)"
+alt_lse "8:ldxr \tmp, [\addr]", "stset \tmp, [\addr]"
+alt_lse " orr \tmp, \tmp, #(1 << \bitnum)", "nop"
+alt_lse " stxr \wtmp, \tmp, [\addr]", "nop"
+alt_lse " cbnz \wtmp, 8b", "nop"
+ .endm
+
#endif /* __ASM_ASSEMBLER_H */
--
2.14.2
^ permalink raw reply related
* [PATCH v2 14/17] arm64: KVM: Add ARCH_WORKAROUND_2 discovery through ARCH_FEATURES_FUNC_ID
From: Marc Zyngier @ 2018-05-29 12:11 UTC (permalink / raw)
To: linux-arm-kernel
In-Reply-To: <20180529121121.24927-1-marc.zyngier@arm.com>
Now that all our infrastructure is in place, let's expose the
availability of ARCH_WORKAROUND_2 to guests. We take this opportunity
to tidy up a couple of SMCCC constants.
Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
arch/arm/include/asm/kvm_host.h | 12 ++++++++++++
arch/arm64/include/asm/kvm_host.h | 23 +++++++++++++++++++++++
arch/arm64/kvm/reset.c | 4 ++++
virt/kvm/arm/psci.c | 18 ++++++++++++++++--
4 files changed, 55 insertions(+), 2 deletions(-)
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index c7c28c885a19..7001fb871429 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -315,6 +315,18 @@ static inline bool kvm_arm_harden_branch_predictor(void)
return false;
}
+#define KVM_SSBD_UNKNOWN -1
+#define KVM_SSBD_FORCE_DISABLE 0
+#define KVM_SSBD_KERNEL 1
+#define KVM_SSBD_FORCE_ENABLE 2
+#define KVM_SSBD_MITIGATED 3
+
+static inline int kvm_arm_have_ssbd(void)
+{
+ /* No way to detect it yet, pretend it is not there. */
+ return KVM_SSBD_UNKNOWN;
+}
+
static inline void kvm_vcpu_load_sysregs(struct kvm_vcpu *vcpu) {}
static inline void kvm_vcpu_put_sysregs(struct kvm_vcpu *vcpu) {}
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 9bef3f69bdcd..95d8a0e15b5f 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -455,6 +455,29 @@ static inline bool kvm_arm_harden_branch_predictor(void)
return cpus_have_const_cap(ARM64_HARDEN_BRANCH_PREDICTOR);
}
+#define KVM_SSBD_UNKNOWN -1
+#define KVM_SSBD_FORCE_DISABLE 0
+#define KVM_SSBD_KERNEL 1
+#define KVM_SSBD_FORCE_ENABLE 2
+#define KVM_SSBD_MITIGATED 3
+
+static inline int kvm_arm_have_ssbd(void)
+{
+ switch (arm64_get_ssbd_state()) {
+ case ARM64_SSBD_FORCE_DISABLE:
+ return KVM_SSBD_FORCE_DISABLE;
+ case ARM64_SSBD_KERNEL:
+ return KVM_SSBD_KERNEL;
+ case ARM64_SSBD_FORCE_ENABLE:
+ return KVM_SSBD_FORCE_ENABLE;
+ case ARM64_SSBD_MITIGATED:
+ return KVM_SSBD_MITIGATED;
+ case ARM64_SSBD_UNKNOWN:
+ default:
+ return KVM_SSBD_UNKNOWN;
+ }
+}
+
void kvm_vcpu_load_sysregs(struct kvm_vcpu *vcpu);
void kvm_vcpu_put_sysregs(struct kvm_vcpu *vcpu);
diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c
index 3256b9228e75..a74311beda35 100644
--- a/arch/arm64/kvm/reset.c
+++ b/arch/arm64/kvm/reset.c
@@ -122,6 +122,10 @@ int kvm_reset_vcpu(struct kvm_vcpu *vcpu)
/* Reset PMU */
kvm_pmu_vcpu_reset(vcpu);
+ /* Default workaround setup is enabled (if supported) */
+ if (kvm_arm_have_ssbd() == KVM_SSBD_KERNEL)
+ vcpu->arch.workaround_flags |= VCPU_WORKAROUND_2_FLAG;
+
/* Reset timer */
return kvm_timer_vcpu_reset(vcpu);
}
diff --git a/virt/kvm/arm/psci.c b/virt/kvm/arm/psci.c
index c4762bef13c6..c95ab4c5a475 100644
--- a/virt/kvm/arm/psci.c
+++ b/virt/kvm/arm/psci.c
@@ -405,7 +405,7 @@ static int kvm_psci_call(struct kvm_vcpu *vcpu)
int kvm_hvc_call_handler(struct kvm_vcpu *vcpu)
{
u32 func_id = smccc_get_function(vcpu);
- u32 val = PSCI_RET_NOT_SUPPORTED;
+ u32 val = SMCCC_RET_NOT_SUPPORTED;
u32 feature;
switch (func_id) {
@@ -417,7 +417,21 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu)
switch(feature) {
case ARM_SMCCC_ARCH_WORKAROUND_1:
if (kvm_arm_harden_branch_predictor())
- val = 0;
+ val = SMCCC_RET_SUCCESS;
+ break;
+ case ARM_SMCCC_ARCH_WORKAROUND_2:
+ switch (kvm_arm_have_ssbd()) {
+ case KVM_SSBD_FORCE_DISABLE:
+ case KVM_SSBD_UNKNOWN:
+ break;
+ case KVM_SSBD_KERNEL:
+ val = SMCCC_RET_SUCCESS;
+ break;
+ case KVM_SSBD_FORCE_ENABLE:
+ case KVM_SSBD_MITIGATED:
+ val = SMCCC_RET_NOT_REQUIRED;
+ break;
+ }
break;
}
break;
--
2.14.2
^ permalink raw reply related
* [PATCH v2 13/17] arm64: KVM: Handle guest's ARCH_WORKAROUND_2 requests
From: Marc Zyngier @ 2018-05-29 12:11 UTC (permalink / raw)
To: linux-arm-kernel
In-Reply-To: <20180529121121.24927-1-marc.zyngier@arm.com>
In order to forward the guest's ARCH_WORKAROUND_2 calls to EL3,
add a small(-ish) sequence to handle it at EL2. Special care must
be taken to track the state of the guest itself by updating the
workaround flags. We also rely on patching to enable calls into
the firmware.
Note that since we need to execute branches, this always executes
after the Spectre-v2 mitigation has been applied.
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
arch/arm64/kernel/asm-offsets.c | 1 +
arch/arm64/kvm/hyp/hyp-entry.S | 38 +++++++++++++++++++++++++++++++++++++-
2 files changed, 38 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c
index 5bdda651bd05..323aeb5f2fe6 100644
--- a/arch/arm64/kernel/asm-offsets.c
+++ b/arch/arm64/kernel/asm-offsets.c
@@ -136,6 +136,7 @@ int main(void)
#ifdef CONFIG_KVM_ARM_HOST
DEFINE(VCPU_CONTEXT, offsetof(struct kvm_vcpu, arch.ctxt));
DEFINE(VCPU_FAULT_DISR, offsetof(struct kvm_vcpu, arch.fault.disr_el1));
+ DEFINE(VCPU_WORKAROUND_FLAGS, offsetof(struct kvm_vcpu, arch.workaround_flags));
DEFINE(CPU_GP_REGS, offsetof(struct kvm_cpu_context, gp_regs));
DEFINE(CPU_USER_PT_REGS, offsetof(struct kvm_regs, regs));
DEFINE(CPU_FP_REGS, offsetof(struct kvm_regs, fp_regs));
diff --git a/arch/arm64/kvm/hyp/hyp-entry.S b/arch/arm64/kvm/hyp/hyp-entry.S
index bffece27b5c1..05d836979032 100644
--- a/arch/arm64/kvm/hyp/hyp-entry.S
+++ b/arch/arm64/kvm/hyp/hyp-entry.S
@@ -106,8 +106,44 @@ el1_hvc_guest:
*/
ldr x1, [sp] // Guest's x0
eor w1, w1, #ARM_SMCCC_ARCH_WORKAROUND_1
+ cbz w1, wa_epilogue
+
+ /* ARM_SMCCC_ARCH_WORKAROUND_2 handling */
+ eor w1, w1, #(ARM_SMCCC_ARCH_WORKAROUND_1 ^ \
+ ARM_SMCCC_ARCH_WORKAROUND_2)
cbnz w1, el1_trap
- mov x0, x1
+
+#ifdef CONFIG_ARM64_SSBD
+alternative_cb arm64_enable_wa2_handling
+ b wa2_end
+alternative_cb_end
+ get_vcpu_ptr x2, x0
+ ldr x0, [x2, #VCPU_WORKAROUND_FLAGS]
+
+ // Sanitize the argument and update the guest flags
+ ldr x1, [sp, #8] // Guest's x1
+ clz w1, w1 // Murphy's device:
+ lsr w1, w1, #5 // w1 = !!w1 without using
+ eor w1, w1, #1 // the flags...
+ bfi x0, x1, #VCPU_WORKAROUND_2_FLAG_SHIFT, #1
+ str x0, [x2, #VCPU_WORKAROUND_FLAGS]
+
+ /* Check that we actually need to perform the call */
+ hyp_ldr_this_cpu x0, arm64_ssbd_callback_required, x2
+ cbz x0, wa2_end
+
+ mov w0, #ARM_SMCCC_ARCH_WORKAROUND_2
+ smc #0
+
+ /* Don't leak data from the SMC call */
+ mov x3, xzr
+wa2_end:
+ mov x2, xzr
+ mov x1, xzr
+#endif
+
+wa_epilogue:
+ mov x0, xzr
add sp, sp, #16
eret
--
2.14.2
^ permalink raw reply related
* [PATCH v2 12/17] arm64: KVM: Add ARCH_WORKAROUND_2 support for guests
From: Marc Zyngier @ 2018-05-29 12:11 UTC (permalink / raw)
To: linux-arm-kernel
In-Reply-To: <20180529121121.24927-1-marc.zyngier@arm.com>
In order to offer ARCH_WORKAROUND_2 support to guests, we need
a bit of infrastructure.
Let's add a flag indicating whether or not the guest uses
SSBD mitigation. Depending on the state of this flag, allow
KVM to disable ARCH_WORKAROUND_2 before entering the guest,
and enable it when exiting it.
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
arch/arm/include/asm/kvm_mmu.h | 5 +++++
arch/arm64/include/asm/kvm_asm.h | 3 +++
arch/arm64/include/asm/kvm_host.h | 3 +++
arch/arm64/include/asm/kvm_mmu.h | 24 ++++++++++++++++++++++
arch/arm64/kvm/hyp/switch.c | 42 +++++++++++++++++++++++++++++++++++++++
virt/kvm/arm/arm.c | 4 ++++
6 files changed, 81 insertions(+)
diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h
index f675162663f0..d2eb24eccf8f 100644
--- a/arch/arm/include/asm/kvm_mmu.h
+++ b/arch/arm/include/asm/kvm_mmu.h
@@ -335,6 +335,11 @@ static inline int kvm_map_vectors(void)
return 0;
}
+static inline int hyp_map_aux_data(void)
+{
+ return 0;
+}
+
#define kvm_phys_to_vttbr(addr) (addr)
#endif /* !__ASSEMBLY__ */
diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
index fefd8cf42c35..d4fbb1356c4c 100644
--- a/arch/arm64/include/asm/kvm_asm.h
+++ b/arch/arm64/include/asm/kvm_asm.h
@@ -33,6 +33,9 @@
#define KVM_ARM64_DEBUG_DIRTY_SHIFT 0
#define KVM_ARM64_DEBUG_DIRTY (1 << KVM_ARM64_DEBUG_DIRTY_SHIFT)
+#define VCPU_WORKAROUND_2_FLAG_SHIFT 0
+#define VCPU_WORKAROUND_2_FLAG (_AC(1, UL) << VCPU_WORKAROUND_2_FLAG_SHIFT)
+
/* Translate a kernel address of @sym into its equivalent linear mapping */
#define kvm_ksym_ref(sym) \
({ \
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 469de8acd06f..9bef3f69bdcd 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -216,6 +216,9 @@ struct kvm_vcpu_arch {
/* Exception Information */
struct kvm_vcpu_fault_info fault;
+ /* State of various workarounds, see kvm_asm.h for bit assignment */
+ u64 workaround_flags;
+
/* Guest debug state */
u64 debug_flags;
diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h
index 6128992c2ded..e3b2ad7dd40a 100644
--- a/arch/arm64/include/asm/kvm_mmu.h
+++ b/arch/arm64/include/asm/kvm_mmu.h
@@ -473,6 +473,30 @@ static inline int kvm_map_vectors(void)
}
#endif
+#ifdef CONFIG_ARM64_SSBD
+DECLARE_PER_CPU_READ_MOSTLY(u64, arm64_ssbd_callback_required);
+
+static inline int hyp_map_aux_data(void)
+{
+ int cpu, err;
+
+ for_each_possible_cpu(cpu) {
+ u64 *ptr;
+
+ ptr = per_cpu_ptr(&arm64_ssbd_callback_required, cpu);
+ err = create_hyp_mappings(ptr, ptr + 1, PAGE_HYP);
+ if (err)
+ return err;
+ }
+ return 0;
+}
+#else
+static inline int hyp_map_aux_data(void)
+{
+ return 0;
+}
+#endif
+
#define kvm_phys_to_vttbr(addr) phys_to_ttbr(addr)
#endif /* __ASSEMBLY__ */
diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c
index d9645236e474..c50cedc447f1 100644
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -15,6 +15,7 @@
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
+#include <linux/arm-smccc.h>
#include <linux/types.h>
#include <linux/jump_label.h>
#include <uapi/linux/psci.h>
@@ -389,6 +390,39 @@ static bool __hyp_text fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code)
return false;
}
+static inline bool __hyp_text __needs_ssbd_off(struct kvm_vcpu *vcpu)
+{
+ if (!cpus_have_const_cap(ARM64_SSBD))
+ return false;
+
+ return !(vcpu->arch.workaround_flags & VCPU_WORKAROUND_2_FLAG);
+}
+
+static void __hyp_text __set_guest_arch_workaround_state(struct kvm_vcpu *vcpu)
+{
+#ifdef CONFIG_ARM64_SSBD
+ /*
+ * The host runs with the workaround always present. If the
+ * guest wants it disabled, so be it...
+ */
+ if (__needs_ssbd_off(vcpu) &&
+ __hyp_this_cpu_read(arm64_ssbd_callback_required))
+ arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_2, 0, NULL);
+#endif
+}
+
+static void __hyp_text __set_host_arch_workaround_state(struct kvm_vcpu *vcpu)
+{
+#ifdef CONFIG_ARM64_SSBD
+ /*
+ * If the guest has disabled the workaround, bring it back on.
+ */
+ if (__needs_ssbd_off(vcpu) &&
+ __hyp_this_cpu_read(arm64_ssbd_callback_required))
+ arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_2, 1, NULL);
+#endif
+}
+
/* Switch to the guest for VHE systems running in EL2 */
int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu)
{
@@ -409,6 +443,8 @@ int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu)
sysreg_restore_guest_state_vhe(guest_ctxt);
__debug_switch_to_guest(vcpu);
+ __set_guest_arch_workaround_state(vcpu);
+
do {
/* Jump in the fire! */
exit_code = __guest_enter(vcpu, host_ctxt);
@@ -416,6 +452,8 @@ int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu)
/* And we're baaack! */
} while (fixup_guest_exit(vcpu, &exit_code));
+ __set_host_arch_workaround_state(vcpu);
+
fp_enabled = fpsimd_enabled_vhe();
sysreg_save_guest_state_vhe(guest_ctxt);
@@ -465,6 +503,8 @@ int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu)
__sysreg_restore_state_nvhe(guest_ctxt);
__debug_switch_to_guest(vcpu);
+ __set_guest_arch_workaround_state(vcpu);
+
do {
/* Jump in the fire! */
exit_code = __guest_enter(vcpu, host_ctxt);
@@ -472,6 +512,8 @@ int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu)
/* And we're baaack! */
} while (fixup_guest_exit(vcpu, &exit_code));
+ __set_host_arch_workaround_state(vcpu);
+
fp_enabled = __fpsimd_enabled_nvhe();
__sysreg_save_state_nvhe(guest_ctxt);
diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
index a4c1b76240df..2d9b4795edb2 100644
--- a/virt/kvm/arm/arm.c
+++ b/virt/kvm/arm/arm.c
@@ -1490,6 +1490,10 @@ static int init_hyp_mode(void)
}
}
+ err = hyp_map_aux_data();
+ if (err)
+ kvm_err("Cannot map host auxilary data: %d\n", err);
+
return 0;
out_err:
--
2.14.2
^ permalink raw reply related
* [PATCH v2 11/17] arm64: KVM: Add HYP per-cpu accessors
From: Marc Zyngier @ 2018-05-29 12:11 UTC (permalink / raw)
To: linux-arm-kernel
In-Reply-To: <20180529121121.24927-1-marc.zyngier@arm.com>
As we're going to require to access per-cpu variables at EL2,
let's craft the minimum set of accessors required to implement
reading a per-cpu variable, relying on tpidr_el2 to contain the
per-cpu offset.
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
arch/arm64/include/asm/kvm_asm.h | 27 +++++++++++++++++++++++++--
1 file changed, 25 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
index f6648a3e4152..fefd8cf42c35 100644
--- a/arch/arm64/include/asm/kvm_asm.h
+++ b/arch/arm64/include/asm/kvm_asm.h
@@ -71,14 +71,37 @@ extern u32 __kvm_get_mdcr_el2(void);
extern u32 __init_stage2_translation(void);
+/* Home-grown __this_cpu_{ptr,read} variants that always work at HYP */
+#define __hyp_this_cpu_ptr(sym) \
+ ({ \
+ void *__ptr = hyp_symbol_addr(sym); \
+ __ptr += read_sysreg(tpidr_el2); \
+ (typeof(&sym))__ptr; \
+ })
+
+#define __hyp_this_cpu_read(sym) \
+ ({ \
+ *__hyp_this_cpu_ptr(sym); \
+ })
+
#else /* __ASSEMBLY__ */
-.macro get_host_ctxt reg, tmp
- adr_l \reg, kvm_host_cpu_state
+.macro hyp_adr_this_cpu reg, sym, tmp
+ adr_l \reg, \sym
mrs \tmp, tpidr_el2
add \reg, \reg, \tmp
.endm
+.macro hyp_ldr_this_cpu reg, sym, tmp
+ adr_l \reg, \sym
+ mrs \tmp, tpidr_el2
+ ldr \reg, [\reg, \tmp]
+.endm
+
+.macro get_host_ctxt reg, tmp
+ hyp_adr_this_cpu \reg, kvm_host_cpu_state, \tmp
+.endm
+
.macro get_vcpu_ptr vcpu, ctxt
get_host_ctxt \ctxt, \vcpu
ldr \vcpu, [\ctxt, #HOST_CONTEXT_VCPU]
--
2.14.2
^ permalink raw reply related
* [PATCH v2 10/17] arm64: ssbd: Add prctl interface for per-thread mitigation
From: Marc Zyngier @ 2018-05-29 12:11 UTC (permalink / raw)
To: linux-arm-kernel
In-Reply-To: <20180529121121.24927-1-marc.zyngier@arm.com>
If running on a system that performs dynamic SSBD mitigation, allow
userspace to request the mitigation for itself. This is implemented
as a prctl call, allowing the mitigation to be enabled or disabled at
will for this particular thread.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
arch/arm64/kernel/Makefile | 1 +
arch/arm64/kernel/ssbd.c | 107 +++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 108 insertions(+)
create mode 100644 arch/arm64/kernel/ssbd.c
diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile
index bf825f38d206..0025f8691046 100644
--- a/arch/arm64/kernel/Makefile
+++ b/arch/arm64/kernel/Makefile
@@ -54,6 +54,7 @@ arm64-obj-$(CONFIG_ARM64_RELOC_TEST) += arm64-reloc-test.o
arm64-reloc-test-y := reloc_test_core.o reloc_test_syms.o
arm64-obj-$(CONFIG_CRASH_DUMP) += crash_dump.o
arm64-obj-$(CONFIG_ARM_SDE_INTERFACE) += sdei.o
+arm64-obj-$(CONFIG_ARM64_SSBD) += ssbd.o
obj-y += $(arm64-obj-y) vdso/ probes/
obj-m += $(arm64-obj-m)
diff --git a/arch/arm64/kernel/ssbd.c b/arch/arm64/kernel/ssbd.c
new file mode 100644
index 000000000000..07b12c034ec2
--- /dev/null
+++ b/arch/arm64/kernel/ssbd.c
@@ -0,0 +1,107 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018 ARM Ltd, All Rights Reserved.
+ */
+
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/thread_info.h>
+
+#include <asm/cpufeature.h>
+
+/*
+ * prctl interface for SSBD
+ */
+static int ssbd_prctl_set(struct task_struct *task, unsigned long ctrl)
+{
+ int state = arm64_get_ssbd_state();
+
+ /* Unsupported */
+ if (state == ARM64_SSBD_UNKNOWN)
+ return -EINVAL;
+
+ /* Treat the unaffected/mitigated state separately */
+ if (state == ARM64_SSBD_MITIGATED) {
+ switch (ctrl) {
+ case PR_SPEC_ENABLE:
+ return -EPERM;
+ case PR_SPEC_DISABLE:
+ case PR_SPEC_FORCE_DISABLE:
+ return 0;
+ }
+ }
+
+ /*
+ * Things are a bit backward here: the arm64 internal API
+ * *enables the mitigation* when the userspace API *disables
+ * speculation*. So much fun.
+ */
+ switch (ctrl) {
+ case PR_SPEC_ENABLE:
+ /* If speculation is force disabled, enable is not allowed */
+ if (state == ARM64_SSBD_FORCE_ENABLE ||
+ task_spec_ssb_force_disable(task))
+ return -EPERM;
+ task_clear_spec_ssb_disable(task);
+ clear_tsk_thread_flag(task, TIF_SSBD);
+ break;
+ case PR_SPEC_DISABLE:
+ if (state == ARM64_SSBD_FORCE_DISABLE)
+ return -EPERM;
+ task_set_spec_ssb_disable(task);
+ set_tsk_thread_flag(task, TIF_SSBD);
+ break;
+ case PR_SPEC_FORCE_DISABLE:
+ if (state == ARM64_SSBD_FORCE_DISABLE)
+ return -EPERM;
+ task_set_spec_ssb_disable(task);
+ task_set_spec_ssb_force_disable(task);
+ set_tsk_thread_flag(task, TIF_SSBD);
+ break;
+ default:
+ return -ERANGE;
+ }
+
+ return 0;
+}
+
+int arch_prctl_spec_ctrl_set(struct task_struct *task, unsigned long which,
+ unsigned long ctrl)
+{
+ switch (which) {
+ case PR_SPEC_STORE_BYPASS:
+ return ssbd_prctl_set(task, ctrl);
+ default:
+ return -ENODEV;
+ }
+}
+
+static int ssbd_prctl_get(struct task_struct *task)
+{
+ switch (arm64_get_ssbd_state()) {
+ case ARM64_SSBD_UNKNOWN:
+ return -EINVAL;
+ case ARM64_SSBD_FORCE_ENABLE:
+ return PR_SPEC_DISABLE;
+ case ARM64_SSBD_KERNEL:
+ if (task_spec_ssb_force_disable(task))
+ return PR_SPEC_PRCTL | PR_SPEC_FORCE_DISABLE;
+ if (task_spec_ssb_disable(task))
+ return PR_SPEC_PRCTL | PR_SPEC_DISABLE;
+ return PR_SPEC_PRCTL | PR_SPEC_ENABLE;
+ case ARM64_SSBD_FORCE_DISABLE:
+ return PR_SPEC_ENABLE;
+ default:
+ return PR_SPEC_NOT_AFFECTED;
+ }
+}
+
+int arch_prctl_spec_ctrl_get(struct task_struct *task, unsigned long which)
+{
+ switch (which) {
+ case PR_SPEC_STORE_BYPASS:
+ return ssbd_prctl_get(task);
+ default:
+ return -ENODEV;
+ }
+}
--
2.14.2
^ permalink raw reply related
* [PATCH v2 09/17] arm64: ssbd: Introduce thread flag to control userspace mitigation
From: Marc Zyngier @ 2018-05-29 12:11 UTC (permalink / raw)
To: linux-arm-kernel
In-Reply-To: <20180529121121.24927-1-marc.zyngier@arm.com>
In order to allow userspace to be mitigated on demand, let's
introduce a new thread flag that prevents the mitigation from
being turned off when exiting to userspace, and doesn't turn
it on on entry into the kernel (with the assumption that the
mitigation is always enabled in the kernel itself).
This will be used by a prctl interface introduced in a later
patch.
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
arch/arm64/include/asm/thread_info.h | 1 +
arch/arm64/kernel/entry.S | 2 ++
2 files changed, 3 insertions(+)
diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h
index 740aa03c5f0d..cbcf11b5e637 100644
--- a/arch/arm64/include/asm/thread_info.h
+++ b/arch/arm64/include/asm/thread_info.h
@@ -94,6 +94,7 @@ void arch_release_task_struct(struct task_struct *tsk);
#define TIF_32BIT 22 /* 32bit process */
#define TIF_SVE 23 /* Scalable Vector Extension in use */
#define TIF_SVE_VL_INHERIT 24 /* Inherit sve_vl_onexec across exec */
+#define TIF_SSBD 25 /* Wants SSB mitigation */
#define _TIF_SIGPENDING (1 << TIF_SIGPENDING)
#define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED)
diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index e6f6e2339b22..28ad8799406f 100644
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -147,6 +147,8 @@ alternative_cb arm64_enable_wa2_handling
alternative_cb_end
ldr_this_cpu \tmp2, arm64_ssbd_callback_required, \tmp1
cbz \tmp2, \targ
+ ldr \tmp2, [tsk, #TSK_TI_FLAGS]
+ tbnz \tmp2, #TIF_SSBD, \targ
mov w0, #ARM_SMCCC_ARCH_WORKAROUND_2
mov w1, #\state
alternative_cb arm64_update_smccc_conduit
--
2.14.2
^ permalink raw reply related
* [PATCH v2 08/17] arm64: ssbd: Restore mitigation status on CPU resume
From: Marc Zyngier @ 2018-05-29 12:11 UTC (permalink / raw)
To: linux-arm-kernel
In-Reply-To: <20180529121121.24927-1-marc.zyngier@arm.com>
On a system where firmware can dynamically change the state of the
mitigation, the CPU will always come up with the mitigation enabled,
including when coming back from suspend.
If the user has requested "no mitigation" via a command line option,
let's enforce it by calling into the firmware again to disable it.
Similarily, for a resume from hibernate, the mitigation could have
been disabled by the boot kernel. Let's ensure that it is set
back on in that case.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
arch/arm64/include/asm/cpufeature.h | 6 ++++++
arch/arm64/kernel/cpu_errata.c | 2 +-
arch/arm64/kernel/hibernate.c | 11 +++++++++++
arch/arm64/kernel/suspend.c | 8 ++++++++
4 files changed, 26 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h
index b0fc3224ce8a..55bc1f073bfb 100644
--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h
@@ -553,6 +553,12 @@ static inline int arm64_get_ssbd_state(void)
#endif
}
+#ifdef CONFIG_ARM64_SSBD
+void arm64_set_ssbd_mitigation(bool state);
+#else
+static inline void arm64_set_ssbd_mitigation(bool state) {}
+#endif
+
#endif /* __ASSEMBLY__ */
#endif
diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index 2fef634e6953..2b9a31a6a16a 100644
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -303,7 +303,7 @@ void __init arm64_enable_wa2_handling(struct alt_instr *alt,
*updptr = cpu_to_le32(aarch64_insn_gen_nop());
}
-static void arm64_set_ssbd_mitigation(bool state)
+void arm64_set_ssbd_mitigation(bool state)
{
switch (psci_ops.conduit) {
case PSCI_CONDUIT_HVC:
diff --git a/arch/arm64/kernel/hibernate.c b/arch/arm64/kernel/hibernate.c
index 1ec5f28c39fc..6b2686d54411 100644
--- a/arch/arm64/kernel/hibernate.c
+++ b/arch/arm64/kernel/hibernate.c
@@ -313,6 +313,17 @@ int swsusp_arch_suspend(void)
sleep_cpu = -EINVAL;
__cpu_suspend_exit();
+
+ /*
+ * Just in case the boot kernel did turn the SSBD
+ * mitigation off behind our back, let's set the state
+ * to what we expect it to be.
+ */
+ switch (arm64_get_ssbd_state()) {
+ case ARM64_SSBD_FORCE_ENABLE:
+ case ARM64_SSBD_KERNEL:
+ arm64_set_ssbd_mitigation(true);
+ }
}
local_daif_restore(flags);
diff --git a/arch/arm64/kernel/suspend.c b/arch/arm64/kernel/suspend.c
index a307b9e13392..70c283368b64 100644
--- a/arch/arm64/kernel/suspend.c
+++ b/arch/arm64/kernel/suspend.c
@@ -62,6 +62,14 @@ void notrace __cpu_suspend_exit(void)
*/
if (hw_breakpoint_restore)
hw_breakpoint_restore(cpu);
+
+ /*
+ * On resume, firmware implementing dynamic mitigation will
+ * have turned the mitigation on. If the user has forcefully
+ * disabled it, make sure their wishes are obeyed.
+ */
+ if (arm64_get_ssbd_state() == ARM64_SSBD_FORCE_DISABLE)
+ arm64_set_ssbd_mitigation(false);
}
/*
--
2.14.2
^ permalink raw reply related
* [PATCH v2 07/17] arm64: ssbd: Skip apply_ssbd if not using dynamic mitigation
From: Marc Zyngier @ 2018-05-29 12:11 UTC (permalink / raw)
To: linux-arm-kernel
In-Reply-To: <20180529121121.24927-1-marc.zyngier@arm.com>
In order to avoid checking arm64_ssbd_callback_required on each
kernel entry/exit even if no mitigation is required, let's
add yet another alternative that by default jumps over the mitigation,
and that gets nop'ed out if we're doing dynamic mitigation.
Think of it as a poor man's static key...
Reviewed-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
arch/arm64/kernel/cpu_errata.c | 14 ++++++++++++++
arch/arm64/kernel/entry.S | 3 +++
2 files changed, 17 insertions(+)
diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index a838a3043d4e..2fef634e6953 100644
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -289,6 +289,20 @@ void __init arm64_update_smccc_conduit(struct alt_instr *alt,
*updptr = cpu_to_le32(insn);
}
+void __init arm64_enable_wa2_handling(struct alt_instr *alt,
+ __le32 *origptr, __le32 *updptr,
+ int nr_inst)
+{
+ BUG_ON(nr_inst != 1);
+ /*
+ * Only allow mitigation on EL1 entry/exit and guest
+ * ARCH_WORKAROUND_2 handling if the SSBD state allows it to
+ * be flipped.
+ */
+ if (arm64_get_ssbd_state() == ARM64_SSBD_KERNEL)
+ *updptr = cpu_to_le32(aarch64_insn_gen_nop());
+}
+
static void arm64_set_ssbd_mitigation(bool state)
{
switch (psci_ops.conduit) {
diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index 29ad672a6abd..e6f6e2339b22 100644
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -142,6 +142,9 @@ alternative_else_nop_endif
// to save/restore them if required.
.macro apply_ssbd, state, targ, tmp1, tmp2
#ifdef CONFIG_ARM64_SSBD
+alternative_cb arm64_enable_wa2_handling
+ b \targ
+alternative_cb_end
ldr_this_cpu \tmp2, arm64_ssbd_callback_required, \tmp1
cbz \tmp2, \targ
mov w0, #ARM_SMCCC_ARCH_WORKAROUND_2
--
2.14.2
^ permalink raw reply related
* [PATCH v2 06/17] arm64: ssbd: Add global mitigation state accessor
From: Marc Zyngier @ 2018-05-29 12:11 UTC (permalink / raw)
To: linux-arm-kernel
In-Reply-To: <20180529121121.24927-1-marc.zyngier@arm.com>
We're about to need the mitigation state in various parts of the
kernel in order to do the right thing for userspace and guests.
Let's expose an accessor that will let other subsystems know
about the state.
Reviewed-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
arch/arm64/include/asm/cpufeature.h | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h
index b50650f3e496..b0fc3224ce8a 100644
--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h
@@ -543,6 +543,16 @@ static inline u64 read_zcr_features(void)
#define ARM64_SSBD_FORCE_ENABLE 2
#define ARM64_SSBD_MITIGATED 3
+static inline int arm64_get_ssbd_state(void)
+{
+#ifdef CONFIG_ARM64_SSBD
+ extern int ssbd_state;
+ return ssbd_state;
+#else
+ return ARM64_SSBD_UNKNOWN;
+#endif
+}
+
#endif /* __ASSEMBLY__ */
#endif
--
2.14.2
^ permalink raw reply related
* [PATCH v2 05/17] arm64: Add 'ssbd' command-line option
From: Marc Zyngier @ 2018-05-29 12:11 UTC (permalink / raw)
To: linux-arm-kernel
In-Reply-To: <20180529121121.24927-1-marc.zyngier@arm.com>
On a system where the firmware implements ARCH_WORKAROUND_2,
it may be useful to either permanently enable or disable the
workaround for cases where the user decides that they'd rather
not get a trap overhead, and keep the mitigation permanently
on or off instead of switching it on exception entry/exit.
In any case, default to the mitigation being enabled.
Reviewed-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
Documentation/admin-guide/kernel-parameters.txt | 17 ++++
arch/arm64/include/asm/cpufeature.h | 6 ++
arch/arm64/kernel/cpu_errata.c | 103 ++++++++++++++++++++----
3 files changed, 110 insertions(+), 16 deletions(-)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index f2040d46f095..ff4ba249a26f 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -4092,6 +4092,23 @@
expediting. Set to zero to disable automatic
expediting.
+ ssbd= [ARM64,HW]
+ Speculative Store Bypass Disable control
+
+ On CPUs that are vulnerable to the Speculative
+ Store Bypass vulnerability and offer a
+ firmware based mitigation, this parameter
+ indicates how the mitigation should be used:
+
+ force-on: Unconditionally enable mitigation for
+ for both kernel and userspace
+ force-off: Unconditionally disable mitigation for
+ for both kernel and userspace
+ kernel: Always enable mitigation in the
+ kernel, and offer a prctl interface
+ to allow userspace to register its
+ interest in being mitigated too.
+
stack_guard_gap= [MM]
override the default stack gap protection. The value
is in page units and it defines how many pages prior
diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h
index 09b0f2a80c8f..b50650f3e496 100644
--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h
@@ -537,6 +537,12 @@ static inline u64 read_zcr_features(void)
return zcr;
}
+#define ARM64_SSBD_UNKNOWN -1
+#define ARM64_SSBD_FORCE_DISABLE 0
+#define ARM64_SSBD_KERNEL 1
+#define ARM64_SSBD_FORCE_ENABLE 2
+#define ARM64_SSBD_MITIGATED 3
+
#endif /* __ASSEMBLY__ */
#endif
diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index 0c76c9f176bb..a838a3043d4e 100644
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -235,6 +235,38 @@ enable_smccc_arch_workaround_1(const struct arm64_cpu_capabilities *entry)
#ifdef CONFIG_ARM64_SSBD
DEFINE_PER_CPU_READ_MOSTLY(u64, arm64_ssbd_callback_required);
+int ssbd_state __read_mostly = ARM64_SSBD_KERNEL;
+
+static const struct ssbd_options {
+ const char *str;
+ int state;
+} ssbd_options[] = {
+ { "force-on", ARM64_SSBD_FORCE_ENABLE, },
+ { "force-off", ARM64_SSBD_FORCE_DISABLE, },
+ { "kernel", ARM64_SSBD_KERNEL, },
+};
+
+static int __init ssbd_cfg(char *buf)
+{
+ int i;
+
+ if (!buf || !buf[0])
+ return -EINVAL;
+
+ for (i = 0; i < ARRAY_SIZE(ssbd_options); i++) {
+ int len = strlen(ssbd_options[i].str);
+
+ if (strncmp(buf, ssbd_options[i].str, len))
+ continue;
+
+ ssbd_state = ssbd_options[i].state;
+ return 0;
+ }
+
+ return -EINVAL;
+}
+early_param("ssbd", ssbd_cfg);
+
void __init arm64_update_smccc_conduit(struct alt_instr *alt,
__le32 *origptr, __le32 *updptr,
int nr_inst)
@@ -278,44 +310,83 @@ static bool has_ssbd_mitigation(const struct arm64_cpu_capabilities *entry,
int scope)
{
struct arm_smccc_res res;
- bool supported = true;
+ bool required = true;
+ s32 val;
WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible());
- if (psci_ops.smccc_version == SMCCC_VERSION_1_0)
+ if (psci_ops.smccc_version == SMCCC_VERSION_1_0) {
+ ssbd_state = ARM64_SSBD_UNKNOWN;
return false;
+ }
- /*
- * The probe function return value is either negative
- * (unsupported or mitigated), positive (unaffected), or zero
- * (requires mitigation). We only need to do anything in the
- * last case.
- */
switch (psci_ops.conduit) {
case PSCI_CONDUIT_HVC:
arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID,
ARM_SMCCC_ARCH_WORKAROUND_2, &res);
- if ((int)res.a0 != 0)
- supported = false;
break;
case PSCI_CONDUIT_SMC:
arm_smccc_1_1_smc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID,
ARM_SMCCC_ARCH_WORKAROUND_2, &res);
- if ((int)res.a0 != 0)
- supported = false;
break;
default:
- supported = false;
+ ssbd_state = ARM64_SSBD_UNKNOWN;
+ return false;
}
- if (supported) {
- __this_cpu_write(arm64_ssbd_callback_required, 1);
+ val = (s32)res.a0;
+
+ switch (val) {
+ case SMCCC_RET_NOT_SUPPORTED:
+ ssbd_state = ARM64_SSBD_UNKNOWN;
+ return false;
+
+ case SMCCC_RET_NOT_REQUIRED:
+ pr_info_once("%s mitigation not required\n", entry->desc);
+ ssbd_state = ARM64_SSBD_MITIGATED;
+ return false;
+
+ case SMCCC_RET_SUCCESS:
+ required = true;
+ break;
+
+ case 1: /* Mitigation not required on this CPU */
+ required = false;
+ break;
+
+ default:
+ WARN_ON(1);
+ return false;
+ }
+
+ switch (ssbd_state) {
+ case ARM64_SSBD_FORCE_DISABLE:
+ pr_info_once("%s disabled from command-line\n", entry->desc);
+ arm64_set_ssbd_mitigation(false);
+ required = false;
+ break;
+
+ case ARM64_SSBD_KERNEL:
+ if (required) {
+ __this_cpu_write(arm64_ssbd_callback_required, 1);
+ arm64_set_ssbd_mitigation(true);
+ }
+ break;
+
+ case ARM64_SSBD_FORCE_ENABLE:
+ pr_info_once("%s forced from command-line\n", entry->desc);
arm64_set_ssbd_mitigation(true);
+ required = true;
+ break;
+
+ default:
+ WARN_ON(1);
+ break;
}
- return supported;
+ return required;
}
#endif /* CONFIG_ARM64_SSBD */
--
2.14.2
^ permalink raw reply related
* [PATCH v2 04/17] arm64: Add ARCH_WORKAROUND_2 probing
From: Marc Zyngier @ 2018-05-29 12:11 UTC (permalink / raw)
To: linux-arm-kernel
In-Reply-To: <20180529121121.24927-1-marc.zyngier@arm.com>
As for Spectre variant-2, we rely on SMCCC 1.1 to provide the
discovery mechanism for detecting the SSBD mitigation.
A new capability is also allocated for that purpose, and a
config option.
Reviewed-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
arch/arm64/Kconfig | 9 ++++++
arch/arm64/include/asm/cpucaps.h | 3 +-
arch/arm64/kernel/cpu_errata.c | 69 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 80 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index eb2cf4938f6d..b2103b4df467 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -938,6 +938,15 @@ config HARDEN_EL2_VECTORS
If unsure, say Y.
+config ARM64_SSBD
+ bool "Speculative Store Bypass Disable" if EXPERT
+ default y
+ help
+ This enables mitigation of the bypassing of previous stores
+ by speculative loads.
+
+ If unsure, say Y.
+
menuconfig ARMV8_DEPRECATED
bool "Emulate deprecated/obsolete ARMv8 instructions"
depends on COMPAT
diff --git a/arch/arm64/include/asm/cpucaps.h b/arch/arm64/include/asm/cpucaps.h
index bc51b72fafd4..8a699c708fc9 100644
--- a/arch/arm64/include/asm/cpucaps.h
+++ b/arch/arm64/include/asm/cpucaps.h
@@ -48,7 +48,8 @@
#define ARM64_HAS_CACHE_IDC 27
#define ARM64_HAS_CACHE_DIC 28
#define ARM64_HW_DBM 29
+#define ARM64_SSBD 30
-#define ARM64_NCAPS 30
+#define ARM64_NCAPS 31
#endif /* __ASM_CPUCAPS_H */
diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index d1a7a68dc142..0c76c9f176bb 100644
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -256,6 +256,67 @@ void __init arm64_update_smccc_conduit(struct alt_instr *alt,
*updptr = cpu_to_le32(insn);
}
+
+static void arm64_set_ssbd_mitigation(bool state)
+{
+ switch (psci_ops.conduit) {
+ case PSCI_CONDUIT_HVC:
+ arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_WORKAROUND_2, state, NULL);
+ break;
+
+ case PSCI_CONDUIT_SMC:
+ arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_2, state, NULL);
+ break;
+
+ default:
+ WARN_ON_ONCE(1);
+ break;
+ }
+}
+
+static bool has_ssbd_mitigation(const struct arm64_cpu_capabilities *entry,
+ int scope)
+{
+ struct arm_smccc_res res;
+ bool supported = true;
+
+ WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible());
+
+ if (psci_ops.smccc_version == SMCCC_VERSION_1_0)
+ return false;
+
+ /*
+ * The probe function return value is either negative
+ * (unsupported or mitigated), positive (unaffected), or zero
+ * (requires mitigation). We only need to do anything in the
+ * last case.
+ */
+ switch (psci_ops.conduit) {
+ case PSCI_CONDUIT_HVC:
+ arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID,
+ ARM_SMCCC_ARCH_WORKAROUND_2, &res);
+ if ((int)res.a0 != 0)
+ supported = false;
+ break;
+
+ case PSCI_CONDUIT_SMC:
+ arm_smccc_1_1_smc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID,
+ ARM_SMCCC_ARCH_WORKAROUND_2, &res);
+ if ((int)res.a0 != 0)
+ supported = false;
+ break;
+
+ default:
+ supported = false;
+ }
+
+ if (supported) {
+ __this_cpu_write(arm64_ssbd_callback_required, 1);
+ arm64_set_ssbd_mitigation(true);
+ }
+
+ return supported;
+}
#endif /* CONFIG_ARM64_SSBD */
#define CAP_MIDR_RANGE(model, v_min, r_min, v_max, r_max) \
@@ -513,6 +574,14 @@ const struct arm64_cpu_capabilities arm64_errata[] = {
.type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM,
ERRATA_MIDR_RANGE_LIST(arm64_harden_el2_vectors),
},
+#endif
+#ifdef CONFIG_ARM64_SSBD
+ {
+ .desc = "Speculative Store Bypass Disable",
+ .capability = ARM64_SSBD,
+ .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM,
+ .matches = has_ssbd_mitigation,
+ },
#endif
{
}
--
2.14.2
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