lib: utils/irqchip: plic: Provide a hartindex to context map

This removes platform-specific arguments to plic_warm_irqchip_init(),
which makes the driver independent from the platform after cold init,
and allows for further refactoring.

Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

include/sbi_utils/irqchip/plic.h

@@ -17,6 +17,7 @@ struct plic_data {
 	unsigned long size;
 	unsigned long num_src;
 	unsigned long flags;
+	s16 context_map[][2];
 };
 
 /** Work around a bug on Ariane that requires enabling interrupts at boot */
@@ -24,6 +25,12 @@ struct plic_data {
 /** PLIC must be delegated to S-mode like T-HEAD C906 and C910 */
 #define PLIC_FLAG_THEAD_DELEGATION	BIT(1)
 
+#define PLIC_M_CONTEXT			0
+#define PLIC_S_CONTEXT			1
+
+#define PLIC_DATA_SIZE(__hart_count)	(sizeof(struct plic_data) + \
+					 (__hart_count) * 2 * sizeof(s16))
+
 /* So far, priorities on all consumers of these functions fit in 8 bits. */
 void plic_priority_save(const struct plic_data *plic, u8 *priority, u32 num);
 
@@ -32,14 +39,13 @@ void plic_priority_restore(const struct plic_data *plic, const u8 *priority,
 
 void plic_delegate(const struct plic_data *plic);
 
-void plic_context_save(const struct plic_data *plic, int context_id,
+void plic_context_save(const struct plic_data *plic, bool smode,
 		       u32 *enable, u32 *threshold, u32 num);
 
-void plic_context_restore(const struct plic_data *plic, int context_id,
+void plic_context_restore(const struct plic_data *plic, bool smode,
 			  const u32 *enable, u32 threshold, u32 num);
 
-int plic_warm_irqchip_init(const struct plic_data *plic,
+int plic_warm_irqchip_init(const struct plic_data *plic);
-			   int m_cntx_id, int s_cntx_id);
 
 int plic_cold_irqchip_init(const struct plic_data *plic);
 

lib/utils/irqchip/fdt_irqchip_plic.c

@@ -12,6 +12,7 @@
 #include <sbi/riscv_io.h>
 #include <sbi/sbi_error.h>
 #include <sbi/sbi_heap.h>
+#include <sbi/sbi_platform.h>
 #include <sbi/sbi_scratch.h>
 #include <sbi_utils/fdt/fdt_helper.h>
 #include <sbi_utils/irqchip/fdt_irqchip.h>
@@ -25,22 +26,6 @@ static unsigned long plic_ptr_offset;
 #define plic_set_hart_data_ptr(__scratch, __plic)			\
 	sbi_scratch_write_type((__scratch), void *, plic_ptr_offset, (__plic))
 
-static unsigned long plic_mcontext_offset;
-
-#define plic_get_hart_mcontext(__scratch)				\
-	(sbi_scratch_read_type((__scratch), long, plic_mcontext_offset) - 1)
-
-#define plic_set_hart_mcontext(__scratch, __mctx)			\
-	sbi_scratch_write_type((__scratch), long, plic_mcontext_offset, (__mctx) + 1)
-
-static unsigned long plic_scontext_offset;
-
-#define plic_get_hart_scontext(__scratch)				\
-	(sbi_scratch_read_type((__scratch), long, plic_scontext_offset) - 1)
-
-#define plic_set_hart_scontext(__scratch, __sctx)			\
-	sbi_scratch_write_type((__scratch), long, plic_scontext_offset, (__sctx) + 1)
-
 void fdt_plic_priority_save(u8 *priority, u32 num)
 {
 	struct sbi_scratch *scratch = sbi_scratch_thishart_ptr();
@@ -59,9 +44,7 @@ void fdt_plic_context_save(bool smode, u32 *enable, u32 *threshold, u32 num)
 {
 	struct sbi_scratch *scratch = sbi_scratch_thishart_ptr();
 
-	plic_context_save(plic_get_hart_data_ptr(scratch),
+	plic_context_save(plic_get_hart_data_ptr(scratch), smode,
-			  smode ? plic_get_hart_scontext(scratch) :
-				  plic_get_hart_mcontext(scratch),
 			  enable, threshold, num);
 }
 
@@ -70,9 +53,7 @@ void fdt_plic_context_restore(bool smode, const u32 *enable, u32 threshold,
 {
 	struct sbi_scratch *scratch = sbi_scratch_thishart_ptr();
 
-	plic_context_restore(plic_get_hart_data_ptr(scratch),
+	plic_context_restore(plic_get_hart_data_ptr(scratch), smode,
-			     smode ? plic_get_hart_scontext(scratch) :
-				     plic_get_hart_mcontext(scratch),
 			     enable, threshold, num);
 }
 
@@ -80,16 +61,14 @@ static int irqchip_plic_warm_init(void)
 {
 	struct sbi_scratch *scratch = sbi_scratch_thishart_ptr();
 
-	return plic_warm_irqchip_init(plic_get_hart_data_ptr(scratch),
+	return plic_warm_irqchip_init(plic_get_hart_data_ptr(scratch));
-				      plic_get_hart_mcontext(scratch),
-				      plic_get_hart_scontext(scratch));
 }
 
-static int irqchip_plic_update_hartid_table(const void *fdt, int nodeoff,
+static int irqchip_plic_update_context_map(const void *fdt, int nodeoff,
-					    struct plic_data *pd)
+					   struct plic_data *pd)
 {
 	const fdt32_t *val;
-	u32 phandle, hwirq, hartid;
+	u32 phandle, hwirq, hartid, hartindex;
 	struct sbi_scratch *scratch;
 	int i, err, count, cpu_offset, cpu_intc_offset;
 
@@ -114,17 +93,18 @@ static int irqchip_plic_update_hartid_table(const void *fdt, int nodeoff,
 		if (err)
 			continue;
 
-		scratch = sbi_hartid_to_scratch(hartid);
+		hartindex = sbi_hartid_to_hartindex(hartid);
+		scratch = sbi_hartindex_to_scratch(hartindex);
 		if (!scratch)
 			continue;
 
 		plic_set_hart_data_ptr(scratch, pd);
 		switch (hwirq) {
 		case IRQ_M_EXT:
-			plic_set_hart_mcontext(scratch, i / 2);
+			pd->context_map[hartindex][PLIC_M_CONTEXT] = i / 2;
 			break;
 		case IRQ_S_EXT:
-			plic_set_hart_scontext(scratch, i / 2);
+			pd->context_map[hartindex][PLIC_S_CONTEXT] = i / 2;
 			break;
 		}
 	}
@@ -135,6 +115,8 @@ static int irqchip_plic_update_hartid_table(const void *fdt, int nodeoff,
 static int irqchip_plic_cold_init(const void *fdt, int nodeoff,
 				  const struct fdt_match *match)
 {
+	struct sbi_scratch *scratch = sbi_scratch_thishart_ptr();
+	const struct sbi_platform *plat = sbi_platform_ptr(scratch);
 	int rc;
 	struct plic_data *pd;
 
@@ -144,19 +126,7 @@ static int irqchip_plic_cold_init(const void *fdt, int nodeoff,
 			return SBI_ENOMEM;
 	}
 
-	if (!plic_mcontext_offset) {
+	pd = sbi_zalloc(PLIC_DATA_SIZE(plat->hart_count));
-		plic_mcontext_offset = sbi_scratch_alloc_type_offset(long);
-		if (!plic_mcontext_offset)
-			return SBI_ENOMEM;
-	}
-
-	if (!plic_scontext_offset) {
-		plic_scontext_offset = sbi_scratch_alloc_type_offset(long);
-		if (!plic_scontext_offset)
-			return SBI_ENOMEM;
-	}
-
-	pd = sbi_zalloc(sizeof(*pd));
 	if (!pd)
 		return SBI_ENOMEM;
 
@@ -166,11 +136,11 @@ static int irqchip_plic_cold_init(const void *fdt, int nodeoff,
 
 	pd->flags = (unsigned long)match->data;
 
-	rc = plic_cold_irqchip_init(pd);
+	rc = irqchip_plic_update_context_map(fdt, nodeoff, pd);
 	if (rc)
 		goto fail_free_data;
 
-	rc = irqchip_plic_update_hartid_table(fdt, nodeoff, pd);
+	rc = plic_cold_irqchip_init(pd);
 	if (rc)
 		goto fail_free_data;
 

lib/utils/irqchip/plic.c

@@ -102,9 +102,11 @@ void plic_delegate(const struct plic_data *plic)
 		writel_relaxed(BIT(0), (char *)plic->addr + THEAD_PLIC_CTRL_REG);
 }
 
-void plic_context_save(const struct plic_data *plic, int context_id,
+void plic_context_save(const struct plic_data *plic, bool smode,
 		       u32 *enable, u32 *threshold, u32 num)
 {
+	u32 hartindex = current_hartindex();
+	s16 context_id = plic->context_map[hartindex][smode];
 	u32 ie_words = plic->num_src / 32 + 1;
 
 	if (num > ie_words)
@@ -116,9 +118,11 @@ void plic_context_save(const struct plic_data *plic, int context_id,
 	*threshold = plic_get_thresh(plic, context_id);
 }
 
-void plic_context_restore(const struct plic_data *plic, int context_id,
+void plic_context_restore(const struct plic_data *plic, bool smode,
 			  const u32 *enable, u32 threshold, u32 num)
 {
+	u32 hartindex = current_hartindex();
+	s16 context_id = plic->context_map[hartindex][smode];
 	u32 ie_words = plic->num_src / 32 + 1;
 
 	if (num > ie_words)
@@ -149,9 +153,11 @@ static int plic_context_init(const struct plic_data *plic, int context_id,
 	return 0;
 }
 
-int plic_warm_irqchip_init(const struct plic_data *plic,
+int plic_warm_irqchip_init(const struct plic_data *plic)
-			   int m_cntx_id, int s_cntx_id)
 {
+	u32 hartindex = current_hartindex();
+	s16 m_cntx_id = plic->context_map[hartindex][PLIC_M_CONTEXT];
+	s16 s_cntx_id = plic->context_map[hartindex][PLIC_S_CONTEXT];
 	bool enable;
 	int ret;
 

platform/fpga/ariane/platform.c

@@ -40,6 +40,9 @@ static struct plic_data plic = {
 	.size = ARIANE_PLIC_SIZE,
 	.num_src = ARIANE_PLIC_NUM_SOURCES,
 	.flags = PLIC_FLAG_ARIANE_BUG,
+	.context_map = {
+		[0] = { 0, 1 },
+	},
 };
 
 static struct aclint_mswi_data mswi = {
@@ -99,7 +102,6 @@ static int ariane_final_init(bool cold_boot)
  */
 static int ariane_irqchip_init(bool cold_boot)
 {
-	u32 hartid = current_hartid();
 	int ret;
 
 	if (cold_boot) {
@@ -108,7 +110,7 @@ static int ariane_irqchip_init(bool cold_boot)
 			return ret;
 	}
 
-	return plic_warm_irqchip_init(&plic, 2 * hartid, 2 * hartid + 1);
+	return plic_warm_irqchip_init(&plic);
 }
 
 /*

platform/fpga/openpiton/platform.c

@@ -44,6 +44,11 @@ static struct plic_data plic = {
 	.size = OPENPITON_DEFAULT_PLIC_SIZE,
 	.num_src = OPENPITON_DEFAULT_PLIC_NUM_SOURCES,
 	.flags = PLIC_FLAG_ARIANE_BUG,
+	.context_map = {
+		[0] = { 0, 1 },
+		[1] = { 2, 3 },
+		[2] = { 4, 5 },
+	},
 };
 
 static struct aclint_mswi_data mswi = {
@@ -130,7 +135,6 @@ static int openpiton_final_init(bool cold_boot)
  */
 static int openpiton_irqchip_init(bool cold_boot)
 {
-	u32 hartid = current_hartid();
 	int ret;
 
 	if (cold_boot) {
@@ -139,7 +143,7 @@ static int openpiton_irqchip_init(bool cold_boot)
 			return ret;
 	}
 
-	return plic_warm_irqchip_init(&plic, 2 * hartid, 2 * hartid + 1);
+	return plic_warm_irqchip_init(&plic);
 }
 
 /*

platform/kendryte/k210/platform.c

@@ -33,6 +33,10 @@ static struct plic_data plic = {
 	.addr = K210_PLIC_BASE_ADDR,
 	.size = K210_PLIC_BASE_SIZE,
 	.num_src = K210_PLIC_NUM_SOURCES,
+	.context_map = {
+		[0] = { 0, 1 },
+		[1] = { 2, 3 },
+	},
 };
 
 static struct aclint_mswi_data mswi = {
@@ -135,7 +139,6 @@ static int k210_final_init(bool cold_boot)
 static int k210_irqchip_init(bool cold_boot)
 {
 	int rc;
-	u32 hartid = current_hartid();
 
 	if (cold_boot) {
 		rc = plic_cold_irqchip_init(&plic);
@@ -143,7 +146,7 @@ static int k210_irqchip_init(bool cold_boot)
 			return rc;
 	}
 
-	return plic_warm_irqchip_init(&plic, hartid * 2, hartid * 2 + 1);
+	return plic_warm_irqchip_init(&plic);
 }
 
 static int k210_ipi_init(void)

platform/nuclei/ux600/platform.c

@@ -66,6 +66,9 @@ static struct plic_data plic = {
 	.addr = UX600_PLIC_ADDR,
 	.size = UX600_PLIC_SIZE,
 	.num_src = UX600_PLIC_NUM_SOURCES,
+	.context_map = {
+		[0] = { 0, -1 },
+	},
 };
 
 static struct aclint_mswi_data mswi = {
@@ -190,7 +193,6 @@ static int ux600_final_init(bool cold_boot)
 static int ux600_irqchip_init(bool cold_boot)
 {
 	int rc;
-	u32 hartid = current_hartid();
 
 	if (cold_boot) {
 		rc = plic_cold_irqchip_init(&plic);
@@ -198,8 +200,7 @@ static int ux600_irqchip_init(bool cold_boot)
 			return rc;
 	}
 
-	return plic_warm_irqchip_init(&plic, (hartid) ? (2 * hartid - 1) : 0,
+	return plic_warm_irqchip_init(&plic);
-				      (hartid) ? (2 * hartid) : -1);
 }
 
 static int ux600_ipi_init(void)

platform/template/platform.c

@@ -37,6 +37,12 @@ static struct plic_data plic = {
 	.addr = PLATFORM_PLIC_ADDR,
 	.size = PLATFORM_PLIC_SIZE,
 	.num_src = PLATFORM_PLIC_NUM_SOURCES,
+	.context_map = {
+		[0] = { 0, 1 },
+		[1] = { 2, 3 },
+		[2] = { 4, 5 },
+		[3] = { 6, 7 },
+	},
 };
 
 static struct aclint_mswi_data mswi = {
@@ -85,7 +91,6 @@ static int platform_final_init(bool cold_boot)
  */
 static int platform_irqchip_init(bool cold_boot)
 {
-	u32 hartid = current_hartid();
 	int ret;
 
 	/* Example if the generic PLIC driver is used */
@@ -95,7 +100,7 @@ static int platform_irqchip_init(bool cold_boot)
 			return ret;
 	}
 
-	return plic_warm_irqchip_init(&plic, 2 * hartid, 2 * hartid + 1);
+	return plic_warm_irqchip_init(&plic);
 }
 
 /*