[v1 2/2] arm: socfpga: Changed to store QSPI reference clock in kHz

[Siew Chin Lim]

Changed to store QSPI reference clock in kHz instead of Hz in
boot scratch cold0 register for Stratix10 and Agilex.

This patch is in preparation for Intel N5X SDRAM driver
support. Reserved 4 bits for Intel N5X SDRAM driver,
and there will be 28 bits to store QSPI reference clock.
Due to limited bits, QSPI reference clock frequency is
converted to kHz from Hz.

Signed-off-by: Siew Chin Lim <elly.siew.chin.lim at intel.com>
Signed-off-by: Tien Fong Chee <tien.fong.chee at intel.com>
---
 arch/arm/mach-socfpga/clock_manager.c              |  5 +--
 .../include/mach/system_manager_soc64.h            | 16 ++++++++-
 arch/arm/mach-socfpga/mailbox_s10.c                | 40 +++++++++++++++++++---
 include/configs/socfpga_soc64_common.h             |  1 +
 4 files changed, 55 insertions(+), 7 deletions(-)

diff --git a/arch/arm/mach-socfpga/clock_manager.c b/arch/arm/mach-socfpga/clock_manager.c
index be426a5cfb..2783b9d18d 100644
--- a/arch/arm/mach-socfpga/clock_manager.c
+++ b/arch/arm/mach-socfpga/clock_manager.c
@@ -67,8 +67,9 @@ int set_cpu_clk_info(void)
 #if IS_ENABLED(CONFIG_TARGET_SOCFPGA_SOC64)
 unsigned int cm_get_qspi_controller_clk_hz(void)
 {
-	return readl(socfpga_get_sysmgr_addr() +
-		     SYSMGR_SOC64_BOOT_SCRATCH_COLD0);
+	return (readl(socfpga_get_sysmgr_addr() +
+		     SYSMGR_SOC64_BOOT_SCRATCH_COLD0) &
+		     SYSMGR_SCRATCH_REG_0_QSPI_REFCLK_MASK) * CLOCK_1K;
 }
 #endif
 
diff --git a/arch/arm/mach-socfpga/include/mach/system_manager_soc64.h b/arch/arm/mach-socfpga/include/mach/system_manager_soc64.h
index 1eb8e7a904..fc4e17821b 100644
--- a/arch/arm/mach-socfpga/include/mach/system_manager_soc64.h
+++ b/arch/arm/mach-socfpga/include/mach/system_manager_soc64.h
@@ -42,7 +42,10 @@ void populate_sysmgr_pinmux(void);
 #define SYSMGR_SOC64_GPO			0xe4
 #define SYSMGR_SOC64_GPI			0xe8
 #define SYSMGR_SOC64_MPU			0xf0
-/* store qspi ref clock */
+/*
+ * Bits[31:28] reserved for N5X DDR retention, bits[27:0] reserved for SOC 64-bit
+ * storing qspi ref clock (kHz)
+ */
 #define SYSMGR_SOC64_BOOT_SCRATCH_COLD0		0x200
 /* store osc1 clock freq */
 #define SYSMGR_SOC64_BOOT_SCRATCH_COLD1		0x204
@@ -85,6 +88,17 @@ void populate_sysmgr_pinmux(void);
 #define SYSMGR_SOC64_HPS_OSC_CLK		0x1358
 #define SYSMGR_SOC64_IODELAY0			0x1400
 
+/*
+ * Bits for SYSMGR_SOC64_BOOT_SCRATCH_COLD0
+ * Bits[31:28] reserved for DM DDR retention, bits[27:0] reserved for SOC 64-bit
+ * storing qspi ref clock (kHz)
+ */
+#define SYSMGR_SCRATCH_REG_0_QSPI_REFCLK_MASK		GENMASK(27, 0)
+#define ALT_SYSMGR_SCRATCH_REG_0_DDR_RETENTION_MASK	BIT(31)
+#define ALT_SYSMGR_SCRATCH_REG_0_DDR_SHA_MASK		BIT(30)
+#define ALT_SYSMGR_SCRATCH_REG_0_DDR_RESET_TYPE_MASK	(BIT(29) | BIT(28))
+#define ALT_SYSMGR_SCRATCH_REG_0_DDR_RESET_TYPE_SHIFT	28
+
 #define SYSMGR_SDMMC				SYSMGR_SOC64_SDMMC
 
 #define SYSMGR_ROMCODEGRP_CTRL_WARMRSTCFGPINMUX	BIT(0)
diff --git a/arch/arm/mach-socfpga/mailbox_s10.c b/arch/arm/mach-socfpga/mailbox_s10.c
index 7dcdae8136..2a13fbb506 100644
--- a/arch/arm/mach-socfpga/mailbox_s10.c
+++ b/arch/arm/mach-socfpga/mailbox_s10.c
@@ -356,6 +356,38 @@ int mbox_qspi_close(void)
 			     0, NULL, 0, 0, NULL);
 }
 
+int mbox_qspi_set_controller_clk_hz(int clk_hz)
+{
+	u32 reg;
+	u32 clk_khz;
+
+	/* We are getting QSPI ref clock and set into sysmgr boot register */
+	/*
+	 * Only clock freq in kHz degree is accepted due to limited bits[27:0]
+	 * is reserved for storing the QSPI clock freq into boot scratch cold0
+	 * register
+	 */
+	if (clk_hz < CLOCK_1K)
+		return -EINVAL;
+
+	clk_khz = clk_hz / CLOCK_1K;
+	printf("QSPI: Reference clock at %d kHz\n", clk_khz);
+
+	/*
+	 * DDR retention bit, SHA comparison bit and reset type bits sharing the
+	 * same scratch register in N5X, ensure the content inside register is
+	 * not overwritten by QSPI ref clock (kHz)
+	 */
+	reg = (readl(socfpga_get_sysmgr_addr() +
+		     SYSMGR_SOC64_BOOT_SCRATCH_COLD0)) &
+		     ~(SYSMGR_SCRATCH_REG_0_QSPI_REFCLK_MASK);
+
+	writel((clk_khz & SYSMGR_SCRATCH_REG_0_QSPI_REFCLK_MASK) | reg,
+	       socfpga_get_sysmgr_addr() + SYSMGR_SOC64_BOOT_SCRATCH_COLD0);
+
+	return 0;
+}
+
 int mbox_qspi_open(void)
 {
 	int ret;
@@ -384,10 +416,10 @@ int mbox_qspi_open(void)
 	if (ret)
 		goto error;
 
-	/* We are getting QSPI ref clock and set into sysmgr boot register */
-	printf("QSPI: Reference clock at %d Hz\n", resp_buf[0]);
-	writel(resp_buf[0],
-	       socfpga_get_sysmgr_addr() + SYSMGR_SOC64_BOOT_SCRATCH_COLD0);
+	/* Store QSPI controller ref clock frequency*/
+	ret = mbox_qspi_set_controller_clk_hz(resp_buf[0]);
+	if (ret)
+		goto error;
 
 	return 0;
 
diff --git a/include/configs/socfpga_soc64_common.h b/include/configs/socfpga_soc64_common.h
index 5afdb10454..6a157298ca 100644
--- a/include/configs/socfpga_soc64_common.h
+++ b/include/configs/socfpga_soc64_common.h
@@ -73,6 +73,7 @@
 
 #ifndef __ASSEMBLY__
 unsigned int cm_get_qspi_controller_clk_hz(void);
+#define CLOCK_1K			1000
 #define CONFIG_CQSPI_REF_CLK		cm_get_qspi_controller_clk_hz()
 #endif
 
-- 
2.13.0