From 530894f508874f4cb3db644ca9ca679ed704f964 Mon Sep 17 00:00:00 2001
From: Keith Packard <keithp@keithp.com>
Date: Mon, 12 May 2014 22:55:38 -0700
Subject: [PATCH] altos/stm: Figure out available flash space based on chip id
 registers

Look at the flash size and the device id registers to figure out how
much flash is available.

Signed-off-by: Keith Packard <keithp@keithp.com>
---
 src/stm/ao_interrupt.c | 32 ++++++++++++++++++++++++++++++++
 src/stm/registers.ld   |  5 +++++
 src/stm/stm32l.h       | 30 ++++++++++++++++++++++++++++++
 3 files changed, 67 insertions(+)

diff --git a/src/stm/ao_interrupt.c b/src/stm/ao_interrupt.c
index 969e6a0f..56cce0c0 100644
--- a/src/stm/ao_interrupt.c
+++ b/src/stm/ao_interrupt.c
@@ -39,6 +39,38 @@ void stm_ignore_isr(void)
 
 const void *stm_interrupt_vector[];
 
+uint32_t
+stm_flash_size(void) {
+	uint16_t	dev_id = stm_dev_id();
+	uint16_t	kbytes = 0;
+
+	switch (dev_id) {
+	case 0x416:	/* cat 1 */
+		kbytes = stm_flash_size_medium.f_size;
+		break;
+	case 0x429:	/* cat 2 */
+		kbytes = stm_flash_size_medium.f_size & 0xff;
+		break;
+	case 0x427:	/* cat 3 */
+		kbytes = stm_flash_size_large.f_size;
+		break;
+	case 0x436:	/* cat 4 */
+		switch (stm_flash_size_large.f_size) {
+		case 0:
+			kbytes = 256;
+			break;
+		case 1:
+			kbytes = 384;
+			break;
+		}
+		break;
+	case 0x437:	/* cat 5 */
+		kbytes = stm_flash_size_large.f_size;
+		break;
+	}
+	return (uint32_t) kbytes * 1024;
+}
+
 void start(void)
 {
 #ifdef AO_BOOT_CHAIN
diff --git a/src/stm/registers.ld b/src/stm/registers.ld
index 8318c75a..d40fd90f 100644
--- a/src/stm/registers.ld
+++ b/src/stm/registers.ld
@@ -52,5 +52,10 @@ stm_scb    = 0xe000ed00;
 
 stm_mpu    = 0xe000ed90;
 
+stm_dbg_mcu = 0xe0042000;
+
 /* calibration data in system memory */
 stm_temp_cal = 0x1ff80078;
+stm_flash_size_medium = 0x1ff8004c;
+stm_flash_size_large = 0x1ff800cc;
+stm_device_id = 0x1ff80050;
diff --git a/src/stm/stm32l.h b/src/stm/stm32l.h
index 302f4d24..9226e9cb 100644
--- a/src/stm/stm32l.h
+++ b/src/stm/stm32l.h
@@ -1492,6 +1492,36 @@ extern struct stm_temp_cal	stm_temp_cal;
 #define stm_temp_cal_cold	25
 #define stm_temp_cal_hot	110
 
+struct stm_dbg_mcu {
+	uint32_t	idcode;
+};
+
+extern struct stm_dbg_mcu	stm_dbg_mcu;
+
+static inline uint16_t
+stm_dev_id(void) {
+	return stm_dbg_mcu.idcode & 0xfff;
+}
+
+struct stm_flash_size {
+	uint16_t	f_size;
+};
+
+extern struct stm_flash_size	stm_flash_size_medium;
+extern struct stm_flash_size	stm_flash_size_large;
+
+/* Returns flash size in bytes */
+extern uint32_t
+stm_flash_size(void);
+
+struct stm_device_id {
+	uint32_t	u_id0;
+	uint32_t	u_id1;
+	uint32_t	u_id2;
+};
+
+extern struct stm_device_id	stm_device_id;
+
 #define STM_NUM_I2C	2
 
 #define STM_I2C_INDEX(channel)	((channel) - 1)
-- 
2.30.2