[PATCH v4 5/5] arch: armv8: fsl-layerscape: export serdes config to environment

[Alex Marginean]

Exports the serdes configuration as an environment variable for LS gen 3
SoCs, so it can be used in u-boot command line.  It should particularly
be useful for applying Linux DT overlays for the given serdes
configuration.
This code is called from arch_misc_init and not from the existing
serdes_init function because it depends on U-Boot environment being set
up.

Signed-off-by: Alex Marginean <alexandru.marginean at nxp.com>
---
 arch/arm/cpu/armv8/fsl-layerscape/Kconfig     |  1 +
 arch/arm/cpu/armv8/fsl-layerscape/cpu.c       | 14 +++++
 .../armv8/fsl-layerscape/fsl_lsch3_serdes.c   | 59 +++++++++++++++++++
 .../include/asm/arch-fsl-layerscape/config.h  |  2 +
 4 files changed, 76 insertions(+)

diff --git a/arch/arm/cpu/armv8/fsl-layerscape/Kconfig b/arch/arm/cpu/armv8/fsl-layerscape/Kconfig
index ed478ddd48..e2b92f0eab 100644
--- a/arch/arm/cpu/armv8/fsl-layerscape/Kconfig
+++ b/arch/arm/cpu/armv8/fsl-layerscape/Kconfig
@@ -242,6 +242,7 @@ config FSL_LSCH2
 	select SYS_FSL_SEC_BE
 
 config FSL_LSCH3
+	select ARCH_MISC_INIT
 	bool
 
 config NXP_LSCH3_2
diff --git a/arch/arm/cpu/armv8/fsl-layerscape/cpu.c b/arch/arm/cpu/armv8/fsl-layerscape/cpu.c
index 639f531649..58fe36f3f1 100644
--- a/arch/arm/cpu/armv8/fsl-layerscape/cpu.c
+++ b/arch/arm/cpu/armv8/fsl-layerscape/cpu.c
@@ -1630,3 +1630,17 @@ __weak int dram_init(void)
 
 	return 0;
 }
+
+#ifdef CONFIG_ARCH_MISC_INIT
+__weak int serdes_misc_init(void)
+{
+	return 0;
+}
+
+int arch_misc_init(void)
+{
+	serdes_misc_init();
+
+	return 0;
+}
+#endif
diff --git a/arch/arm/cpu/armv8/fsl-layerscape/fsl_lsch3_serdes.c b/arch/arm/cpu/armv8/fsl-layerscape/fsl_lsch3_serdes.c
index 1a747a9e3d..d143864af1 100644
--- a/arch/arm/cpu/armv8/fsl-layerscape/fsl_lsch3_serdes.c
+++ b/arch/arm/cpu/armv8/fsl-layerscape/fsl_lsch3_serdes.c
@@ -600,3 +600,62 @@ void fsl_serdes_init(void)
 		    serdes3_prtcl_map);
 #endif
 }
+
+int serdes_set_env(int sd, int rcwsr, int sd_prctl_mask, int sd_prctl_shift)
+{
+	struct ccsr_gur __iomem *gur = (void *)(CONFIG_SYS_FSL_GUTS_ADDR);
+	char scfg[16], snum[16];
+	int cfgr = 0;
+	u32 cfg;
+
+	cfg = gur_in32(&gur->rcwsr[rcwsr - 1]) & sd_prctl_mask;
+	cfg >>= sd_prctl_shift;
+	cfg = serdes_get_number(sd, cfg);
+
+#if defined(SRDS_BITS_PER_LANE)
+	/*
+	 * reverse lanes, lane 0 should be printed first so it must be moved to
+	 * high order bits.
+	 * For example bb58 should read 85bb, lane 0 being protocol 8.
+	 * This only applies to SoCs that define SRDS_BITS_PER_LANE and have
+	 * independent per-lane protocol configuration, at this time LS1028A and
+	 * LS1088A. LS2 and LX2 SoCs encode the full protocol mix across all
+	 * lanes as a single value.
+	 */
+	for (int i = 0; i < SRDS_MAX_LANES; i++) {
+		int tmp;
+
+		tmp = cfg >> (i * SRDS_BITS_PER_LANE);
+		tmp &= GENMASK(SRDS_BITS_PER_LANE - 1, 0);
+		tmp <<= (SRDS_MAX_LANES - i - 1) * SRDS_BITS_PER_LANE;
+		cfgr |= tmp;
+	}
+#endif /* SRDS_BITS_PER_LANE */
+
+	snprintf(snum, 16, "serdes%d", sd);
+	snprintf(scfg, 16, "%x", cfgr);
+	env_set(snum, scfg);
+
+	return 0;
+}
+
+int serdes_misc_init(void)
+{
+#ifdef CONFIG_SYS_FSL_SRDS_1
+	serdes_set_env(FSL_SRDS_1, FSL_CHASSIS3_SRDS1_REGSR,
+		       FSL_CHASSIS3_SRDS1_PRTCL_MASK,
+		       FSL_CHASSIS3_SRDS1_PRTCL_SHIFT);
+#endif
+#ifdef CONFIG_SYS_FSL_SRDS_2
+	serdes_set_env(FSL_SRDS_2, FSL_CHASSIS3_SRDS2_REGSR,
+		       FSL_CHASSIS3_SRDS2_PRTCL_MASK,
+		       FSL_CHASSIS3_SRDS2_PRTCL_SHIFT);
+#endif
+#ifdef CONFIG_SYS_NXP_SRDS_3
+	serdes_set_env(NXP_SRDS_3, FSL_CHASSIS3_SRDS3_REGSR,
+		       FSL_CHASSIS3_SRDS3_PRTCL_MASK,
+		       FSL_CHASSIS3_SRDS3_PRTCL_SHIFT);
+#endif
+
+	return 0;
+}
diff --git a/arch/arm/include/asm/arch-fsl-layerscape/config.h b/arch/arm/include/asm/arch-fsl-layerscape/config.h
index a83c70ece2..ddd9390df4 100644
--- a/arch/arm/include/asm/arch-fsl-layerscape/config.h
+++ b/arch/arm/include/asm/arch-fsl-layerscape/config.h
@@ -123,6 +123,7 @@
 #define CONFIG_SYS_PAGE_SIZE		0x10000
 
 #define	SRDS_MAX_LANES	4
+#define	SRDS_BITS_PER_LANE	4
 
 /* TZ Protection Controller Definitions */
 #define TZPC_BASE				0x02200000
@@ -252,6 +253,7 @@
 #define TZPCDECPROT_2_CLR_BASE			(TZPC_BASE + 0x820)
 
 #define	SRDS_MAX_LANES	4
+#define	SRDS_BITS_PER_LANE	4
 
 #define CONFIG_SYS_FSL_OCRAM_BASE		0x18000000 /* initial RAM */
 #define SYS_FSL_OCRAM_SPACE_SIZE		0x00200000 /* 2M */
-- 
2.17.1