[PATCH 1/2] ARM: stm32mp: ddrctl: add STM32MP131 RAM size querying support

[Ahmad Fatoum]

Full buswidth for STM32MP131 means 2 byte wide, not 4 as the memory bus
is restricted to 16-bit. Teach barebox the difference.

Signed-off-by: Ahmad Fatoum <a.fatoum at pengutronix.de>
---
 arch/arm/mach-stm32mp/ddrctrl.c               | 26 ++++++++++++++-----
 arch/arm/mach-stm32mp/include/mach/revision.h |  8 ++++++
 2 files changed, 27 insertions(+), 7 deletions(-)

diff --git a/arch/arm/mach-stm32mp/ddrctrl.c b/arch/arm/mach-stm32mp/ddrctrl.c
index 93996d0afc79..7f0944d7e77c 100644
--- a/arch/arm/mach-stm32mp/ddrctrl.c
+++ b/arch/arm/mach-stm32mp/ddrctrl.c
@@ -9,6 +9,7 @@
 #include <mach/ddr_regs.h>
 #include <mach/entry.h>
 #include <mach/stm32.h>
+#include <mach/revision.h>
 #include <asm/barebox-arm.h>
 #include <asm/memory.h>
 #include <pbl.h>
@@ -62,7 +63,8 @@ enum ddrctrl_buswidth {
 };
 
 static unsigned long ddrctrl_addrmap_ramsize(struct stm32mp1_ddrctl __iomem *d,
-					     enum ddrctrl_buswidth buswidth)
+					     enum ddrctrl_buswidth buswidth,
+					     unsigned nb_bytes)
 {
 	unsigned banks = 3, cols = 12, rows = 16;
 	u32 reg;
@@ -99,21 +101,26 @@ static unsigned long ddrctrl_addrmap_ramsize(struct stm32mp1_ddrctl __iomem *d,
 	if (LINE_UNUSED(reg, ADDRMAP6_ROW_B13)) rows--;
 	if (LINE_UNUSED(reg, ADDRMAP6_ROW_B12)) rows--;
 
-	return memory_sdram_size(cols, rows, BIT(banks), 4 / BIT(buswidth));
+	return memory_sdram_size(cols, rows, BIT(banks), nb_bytes / BIT(buswidth));
 }
 
-static inline unsigned ddrctrl_ramsize(void __iomem *base)
+static inline unsigned ddrctrl_ramsize(void __iomem *base, unsigned nb_bytes)
 {
 	struct stm32mp1_ddrctl __iomem *ddrctl = base;
 	unsigned buswidth = readl(&ddrctl->mstr) & DDRCTRL_MSTR_DATA_BUS_WIDTH_MASK;
 	buswidth >>= DDRCTRL_MSTR_DATA_BUS_WIDTH_SHIFT;
 
-	return ddrctrl_addrmap_ramsize(ddrctl, buswidth);
+	return ddrctrl_addrmap_ramsize(ddrctl, buswidth, nb_bytes);
 }
 
 static inline unsigned stm32mp1_ddrctrl_ramsize(void)
 {
-	return ddrctrl_ramsize(IOMEM(STM32_DDRCTL_BASE));
+	u32 nb_bytes = 4;
+
+	if (cpu_stm32_is_stm32mp13())
+		nb_bytes /= 2;
+
+	return ddrctrl_ramsize(IOMEM(STM32_DDRCTL_BASE), nb_bytes);
 }
 
 void __noreturn stm32mp1_barebox_entry(void *boarddata)
@@ -126,17 +133,22 @@ static int stm32mp1_ddr_probe(struct device_d *dev)
 {
 	struct resource *iores;
 	void __iomem *base;
+	unsigned long nb_bytes;
 
 	iores = dev_request_mem_resource(dev, 0);
 	if (IS_ERR(iores))
 		return PTR_ERR(iores);
 	base = IOMEM(iores->start);
 
-	return arm_add_mem_device("ram0", STM32_DDR_BASE, ddrctrl_ramsize(base));
+	nb_bytes = (unsigned long)device_get_match_data(dev);
+
+	return arm_add_mem_device("ram0", STM32_DDR_BASE,
+				  ddrctrl_ramsize(base, nb_bytes));
 }
 
 static __maybe_unused struct of_device_id stm32mp1_ddr_dt_ids[] = {
-	{ .compatible = "st,stm32mp1-ddr" },
+	{ .compatible = "st,stm32mp1-ddr", .data = (void *)4 },
+	{ .compatible = "st,stm32mp13-ddr", .data = (void *)2 },
 	{ /* sentinel */ }
 };
 
diff --git a/arch/arm/mach-stm32mp/include/mach/revision.h b/arch/arm/mach-stm32mp/include/mach/revision.h
index 2ef8ef30c3ae..c141b925a156 100644
--- a/arch/arm/mach-stm32mp/include/mach/revision.h
+++ b/arch/arm/mach-stm32mp/include/mach/revision.h
@@ -32,6 +32,14 @@
 #define CPU_STM32MP151Fxx	0x050000AE
 #define CPU_STM32MP151Dxx	0x050000AF
 
+#define cpu_stm32_is(mask, val) ({ \
+	u32 type; \
+	__stm32mp_get_cpu_type(&type) == 0 ? (type & mask) == val : 0; \
+})
+
+#define cpu_stm32_is_stm32mp15() cpu_stm32_is(0xFFFF0000, 0x05000000)
+#define cpu_stm32_is_stm32mp13() cpu_stm32_is(0xFFFF0000, 0x05010000)
+
 /* silicon revisions */
 #define CPU_REV_A	0x1000
 #define CPU_REV_B	0x2000
-- 
2.30.2