[U-Boot] [PATCH V2 11/11] imx: mx7d: isolate resources to domain 0 for A7 core

[Peng Fan]

From: Peng Fan <peng.fan at nxp.com>

In current design, if any peripheral was assigned to both A7 and M4,
it will receive ipg_stop or ipg_wait when any of the 2 platforms
enter low power mode. We will have a risk that, if A7 enter wait,
M4 enter stop, peripheral will have chance to get ipg_stop and ipg_wait
asserted same time. Also if M4 enters stop mode, A7 will have no
chance to access the peripheral.
There are 26 peripherals affected by this IC issue:
SIM2(sim2/emvsim2)
SIM1(sim1/emvsim1)
UART1/UART2/UART3/UART4/UART5/UART6/UART7
SAI1/SAI2/SAI3
WDOG1/WDOG2/WDOG3/WDOG4
GPT1/GPT2/GPT3/GPT4
PWM1/PWM2/PWM3/PWM4
ENET1/ENET2
Software Workaround:
The solution is to set the peripherals to Domain0 by A core, since A core
in Domain0. The peripherals which will be used by M4, will be set to Domain1
by M4.
For example, A core set WDOG4 to domain0, but when M4 boots up, M4 will
set WDOG4 to domain1, because M4 will use WDOG4.

So the peripherals are not shared by them. This way requires
the uboot implemented the RDC driver and set the 26 IPs above
to domain 0 only. M4 image will set the M4 to domain 1 and
set peripheral which it will use to domain 1.

This patch enables the CONFIG_IMX_RDC and CONFIG_IMX_BOOTAUX for
i.MX7D SABRESD board, and setup the 26 IP resources to domain 0.

Signed-off-by: Ye.Li <ye.li at nxp.com>
Signed-off-by: Peng Fan <peng.fan at nxp.com>
---

V2:
 update commit log

 arch/arm/cpu/armv7/mx7/soc.c  | 64 +++++++++++++++++++++++++++++++++++++++++++
 configs/mx7dsabresd_defconfig |  2 ++
 2 files changed, 66 insertions(+)

diff --git a/arch/arm/cpu/armv7/mx7/soc.c b/arch/arm/cpu/armv7/mx7/soc.c
index 2121ff2..ede7d53 100644
--- a/arch/arm/cpu/armv7/mx7/soc.c
+++ b/arch/arm/cpu/armv7/mx7/soc.c
@@ -12,6 +12,8 @@
 #include <asm/imx-common/boot_mode.h>
 #include <asm/imx-common/dma.h>
 #include <asm/imx-common/hab.h>
+#include <asm/imx-common/rdc-sema.h>
+#include <asm/arch/imx-rdc.h>
 #include <asm/arch/crm_regs.h>
 #include <dm.h>
 #include <imx_thermal.h>
@@ -29,6 +31,65 @@ U_BOOT_DEVICE(imx7_thermal) = {
 };
 #endif
 
+#ifdef CONFIG_IMX_RDC
+/*
+ * In current design, if any peripheral was assigned to both A7 and M4,
+ * it will receive ipg_stop or ipg_wait when any of the 2 platforms enter
+ * low power mode. So M4 sleep will cause some peripherals fail to work
+ * at A7 core side. At default, all resources are in domain 0 - 3.
+ *
+ * There are 26 peripherals impacted by this IC issue:
+ * SIM2(sim2/emvsim2)
+ * SIM1(sim1/emvsim1)
+ * UART1/UART2/UART3/UART4/UART5/UART6/UART7
+ * SAI1/SAI2/SAI3
+ * WDOG1/WDOG2/WDOG3/WDOG4
+ * GPT1/GPT2/GPT3/GPT4
+ * PWM1/PWM2/PWM3/PWM4
+ * ENET1/ENET2
+ * Software Workaround:
+ * Here we setup some resources to domain 0 where M4 codes will move
+ * the M4 out of this domain. Then M4 is not able to access them any longer.
+ * This is a workaround for ic issue. So the peripherals are not shared
+ * by them. This way requires the uboot implemented the RDC driver and
+ * set the 26 IPs above to domain 0 only. M4 code will assign resource
+ * to its own domain, if it want to use the resource.
+ */
+static rdc_peri_cfg_t const resources[] = {
+	(RDC_PER_SIM1 | RDC_DOMAIN(0)),
+	(RDC_PER_SIM2 | RDC_DOMAIN(0)),
+	(RDC_PER_UART1 | RDC_DOMAIN(0)),
+	(RDC_PER_UART2 | RDC_DOMAIN(0)),
+	(RDC_PER_UART3 | RDC_DOMAIN(0)),
+	(RDC_PER_UART4 | RDC_DOMAIN(0)),
+	(RDC_PER_UART5 | RDC_DOMAIN(0)),
+	(RDC_PER_UART6 | RDC_DOMAIN(0)),
+	(RDC_PER_UART7 | RDC_DOMAIN(0)),
+	(RDC_PER_SAI1 | RDC_DOMAIN(0)),
+	(RDC_PER_SAI2 | RDC_DOMAIN(0)),
+	(RDC_PER_SAI3 | RDC_DOMAIN(0)),
+	(RDC_PER_WDOG1 | RDC_DOMAIN(0)),
+	(RDC_PER_WDOG2 | RDC_DOMAIN(0)),
+	(RDC_PER_WDOG3 | RDC_DOMAIN(0)),
+	(RDC_PER_WDOG4 | RDC_DOMAIN(0)),
+	(RDC_PER_GPT1 | RDC_DOMAIN(0)),
+	(RDC_PER_GPT2 | RDC_DOMAIN(0)),
+	(RDC_PER_GPT3 | RDC_DOMAIN(0)),
+	(RDC_PER_GPT4 | RDC_DOMAIN(0)),
+	(RDC_PER_PWM1 | RDC_DOMAIN(0)),
+	(RDC_PER_PWM2 | RDC_DOMAIN(0)),
+	(RDC_PER_PWM3 | RDC_DOMAIN(0)),
+	(RDC_PER_PWM4 | RDC_DOMAIN(0)),
+	(RDC_PER_ENET1 | RDC_DOMAIN(0)),
+	(RDC_PER_ENET2 | RDC_DOMAIN(0)),
+};
+
+static void isolate_resource(void)
+{
+	imx_rdc_setup_peripherals(resources, ARRAY_SIZE(resources));
+}
+#endif
+
 #if defined(CONFIG_SECURE_BOOT)
 struct imx_sec_config_fuse_t const imx_sec_config_fuse = {
 	.bank = 1,
@@ -163,6 +224,9 @@ int arch_cpu_init(void)
 	mxs_dma_init();
 #endif
 
+	if (IS_ENABLED(CONFIG_IMX_RDC))
+		isolate_resource();
+
 	return 0;
 }
 
diff --git a/configs/mx7dsabresd_defconfig b/configs/mx7dsabresd_defconfig
index 420d13e..1d262c1 100644
--- a/configs/mx7dsabresd_defconfig
+++ b/configs/mx7dsabresd_defconfig
@@ -1,6 +1,8 @@
 CONFIG_ARM=y
 CONFIG_ARCH_MX7=y
 CONFIG_TARGET_MX7DSABRESD=y
+CONFIG_IMX_RDC=y
+CONFIG_IMX_BOOTAUX=y
 CONFIG_SYS_EXTRA_OPTIONS="IMX_CONFIG=board/freescale/mx7dsabresd/imximage.cfg,MX7D"
 # CONFIG_CMD_BOOTD is not set
 # CONFIG_CMD_IMI is not set
-- 
2.6.2